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Vinegar consumption can attenuate postprandial glucose and insulin responses; a systematic review and meta-analysis of clinical trials
Abstract
Objective:
Postprandial hyperglycemia plays a decisive role in the development of chronic metabolic disorders. The effect of vinegar intake with a meal on postprandial glucose has been studied in several trials with conflicting results.
Research methods and procedures:
The purpose of the current study was to systematically review control trials that report on the effect of vinegar intake on postprandial glucose response. Postprandial insulin response was considered as secondary outcome.
Results:
The pooled analysis of studies revealed a significant mean glucose and insulin area under the curve (AUC) reduction in participants who consumed vinegar compared with the control group (standard mean difference=-0.60, 95%CI -1.08 to -0.11, p=0.01 and -1.30, 95%CI -1.98 to -0.62, p<0.001, respectively).
Conclusions:
The findings suggest that vinegar can be effective in reducing postprandial glucose and insulin levels, indicating it could be considered as an adjunctive tool for improving glycemic control.
... Evidence suggests that in conditions like hypertension, inflammation, and diabetes mellitus, the crucial function of the endothelium as a vasodilator is impaired leading to ineffective vasodilation. 4,[6][7][8][9] In addition to anti-hypertensive drugs, dietary components such as vinegar are promising for reducing hypertension. 10 Vinegar has recently attracted considerable attention because of its numerous health benefits, such as anti-hyperglycemic, anti-hypercholesterolemia, antihypertension, antimicrobial, antithrombotic, and anti-cancer effects. ...
... 53 Additionally, obese people have a remarkably subordinate acetic acid turnover compared with healthy people, which may provide some explanation for the variable effects of dietary acetic acid supplementation. 8,51 According to studies, vinegar consumption promotes the feeling of satiety in people. Although this should have resulted in body weight regulation, no statistically significant anthropometric improvement was seen among overweight or obese participants. ...
... Although this should have resulted in body weight regulation, no statistically significant anthropometric improvement was seen among overweight or obese participants. 8 Increased dietary acetic acid has been shown to improve metabolic outcomes in rodents in preclinical studies. [54][55][56] A meta-analysis by Valdes et al. also showed that individuals with type 2 diabetes or obesity might benefit from supplementing their diet with dietary acetic acid, which has no adverse side effects and reduces plasma triacylglycerol and Fig. 2. Non-linear dose-response relations between vinegar and unstandardized mean difference in systolic blood pressure. ...
Background
There are controversial findings regarding the effect of vinegar on blood pressure based on the evidence accumulated so far.
Methods
A systematic search was conducted through PubMed, Scopus, and ISI Web of Science up to April 2022. We estimated the change in blood pressure for each 30 ml/d increments in vinegar consumption in each trial and then, calculated the mean difference (MD) and 95%CI using a fixed-effects model. A dose-response meta-analysis of differences in means provided us with the estimation of the dose-dependent effect. The certainty of evidence was rated by the GRADE tool.
Results
Each 30 ml/d increment in vinegar consumption reduced SBP by -3.25 mmHg (95%CI: -5.54, -0.96; I² = 67.5%, GRADE=low). Levels of SBP decreased linearly and slightly (Pnonlinearity = 0.69, Pdose-response = 0.02) up to vinegar consumption of 30 ml/d (MD30ml/d: -3.36, 95%CI: -5.77, -0.94). Each 30 ml/d increment in vinegar consumption reduced DBP by -3.33 mmHg (95%CI: -4.16, -2.49; I² = 57.1%, GRADE=low). Levels of DBP decreased linearly and slightly (Pnonlinearity = 0.47, Pdose-response = 0.004) up to vinegar consumption of 30 ml/d (MD30ml/d: -2.61, 95%CI: -4.15, -1.06)
Conclusions
According to the findings, vinegar significantly reduces systolic and diastolic blood pressure and may be considered an adjunct to hypertension treatment. Thus, clinicians could incorporate vinegar consumption as part of their dietary advice for patients.
... 25,26 Vinegar consumption in adults with T2DM reduces fasting and postprandial circulating glucose and enhances insulin secretion. 27 The promising therapeutic effects gained from acetic acid consumption suggest it may represent a feasible adjunct therapy for the management of metabolic diseases. ...
... Additionally, studies solely investigating postprandial effects of acetic acid consumption were excluded, because two published systematic reviews have previously evaluated postprandial effects of vinegar consumption on human adult metabolic profiles. 27,31 Data Extraction and Risk of Bias Assessment Data from included studies was extracted by one reviewer (D. S. V.) and verified by a second (D. S.). ...
... 64 Indeed, the effect of dietary acetic acid supplementation on FBG levels in individuals with T2DM is consistent with acute studies that report improved regulation of glucose and insulin levels in adults with metabolic dysfunction and T2DM after acute vinegar consumption. 27,65 The mean difference of À35.73 mg/dL seen in this meta-analysis also suggests that longer-term supplementation reduces FBG to a greater extent than that seen after acute supplementation. 66 A primary mechanism through which acetic acid is proposed to have therapeutic action is via binding of G proteinecoupled receptor 43 (GPR43), which is expressed on human peripheral blood mononuclear cells, adipose cells, and in colonic cells, of which acetic acid is a strong activator at physiological concentrations of 50 to 200 mmol/L. ...
Background
Acetic acid is a short-chain fatty acid that has demonstrated biomedical potential as a dietary therapeutic agent for the management of chronic and metabolic illness comorbidities. In human beings, its consumption may improve glucose regulation and insulin sensitivity in individuals with cardiometabolic conditions and type 2 diabetes mellitus. Published clinical trial evidence evaluating its sustained supplementation effects on metabolic outcomes is inconsistent.
Objective
This systematic review and meta-analysis summarized available evidence on potential therapeutic effects of dietary acetic acid supplementation via consumption of acetic acid–rich beverages and food sources on metabolic and anthropometric outcomes.
Methods
A systematic search was conducted in Medline, Scopus, EMBASE, CINAHL Plus, and Web of Science from database inception until October 2020. Randomized controlled trials conducted in adults evaluating the effect of dietary acetic acid supplementation for a minimum of 1 week were included. Meta-analyses were performed using a random-effects model on fasting blood glucose (FBG), triacylglycerol (TAG), high-density lipoprotein (HDL), low-density lipoprotein (LDL), glycated hemoglobin (HbA1c), body mass index (BMI), and body fat percentage. Statistical heterogeneity was assessed by calculation of Q and I² statistics, and publication bias was assessed by calculation of Egger’s regression asymmetry and Begg’s test.
Results
Sixteen studies were included, involving 910 participants who consumed between 750 and 3600 mg acetic acid daily in interventions lasting an average of 8 weeks. Dietary acetic acid supplementation resulted in significant reductions in TAG concentrations in overweight and obese but otherwise healthy individuals (mean difference [MD] = −20.51 mg/dL [95% confidence intervals = −32.98, −8.04], P = .001) and people with type 2 diabetes (MD = −7.37 mg/dL [−10.15, −4.59], P < .001). Additionally, acetic acid supplementation significantly reduced FBG levels (MD = −35.73 mg/dL [−63.79, −7.67], P = .01) in subjects with type 2 diabetes compared with placebo and low-dose comparators. No other changes were seen for other metabolic or anthropometric outcomes assessed. Five of the 16 studies did not specify the dose of acetic acid delivered, and no studies measured blood acetate concentrations. Only one study controlled for background acetic acid-rich food consumption during intervention periods. Most studies had an unclear or high risk of bias.
Conclusion
Supplementation with dietary acetic acid is well tolerated, has no adverse side effects, and has clinical potential to reduce plasma TAG and FBG concentrations in individuals with type 2 diabetes, and to reduce TAG levels in people who are overweight or obese. No significant effects of dietary acetic acid consumption were seen on HbA1c, HDL, or anthropometric markers. High-quality, longer-term studies in larger cohorts are required to confirm whether dietary acetic acid can act as an adjuvant therapeutic agent in metabolic comorbidities management.
... Participants were also instructed to balance the consumption of macronutrient at every meal to achieve a lower GL diet [15]. They were led by three simple steps to follow when selecting or preparing a meal. ...
... In order to reduce the post-prandial blood glucose spikes upon consumption of high GI foods, participants were advised to combine high GI foods with vinegar, dairy products, pickles, proteins or fats. A number of scientific research papers have reported a reduction of the post-prandial glycaemic response upon consumption of higher GI foods in combination with these foods and macronutrients [15,16]. ...
Abstract: A randomised controlled trial to measure the effects of integrating real-time continuous glucose monitor (rtCGM) into a low glycaemic index (GI) and glycaemic load (GL) dietary interven- tion on dietary intake, body composition and specific metabolic parameters was carried out. A total of 40 overweight young adults [(means ± SD) age: 26.4 ± 5.3 years, BMI: 29.4 ± 4.7 kg/m2] were randomised into an intervention and control groups for a period of eight weeks. Both groups received nutrition education on low GI and GL foods. The intervention group also received an rtCGM system to monitor their glucose levels 24 h a day. While controlling for physical activities and GI and GL nutrition knowledge, the results indicated that the rtCGM system further improved body weight, BMI, fat mass, fasting plasma glucose, HbA1c, total cholesterol, HDL cholesterol and LDL cholesterol in the intervention group (p < 0.05). This trial unveils the robustness of the rtCGM where non-diabetic overweight and obese young adults can benefit from this device and utilise it as a management tool for overweight and obesity and a primary prevention tool for type 2 diabetes, as it provides real-time and personalised information on physiological changes.
... Participants were also instructed to balance the consumption of macronutrient at every meal to achieve a lower GL diet [15]. They were led by three simple steps to follow when selecting or preparing a meal. ...
... In order to reduce the post-prandial blood glucose spikes upon consumption of high GI foods, participants were advised to combine high GI foods with vinegar, dairy products, pickles, proteins or fats. A number of scientific research papers have reported a reduction of the post-prandial glycaemic response upon consumption of higher GI foods in combination with these foods and macronutrients [15,16]. ...
A randomised controlled trial to measure the effects of integrating real-time continuous glucose monitor (rtCGM) into a low glycaemic index (GI) and glycaemic load (GL) dietary intervention on dietary intake, body composition and specific metabolic parameters was carried out. A total of 40 overweight young adults [(means ± SD) age: 26.4 ± 5.3 years, BMI: 29.4 ± 4.7 kg/m2] were randomised into an intervention and control groups for a period of eight weeks. Both groups received nutrition education on low GI and GL foods. The intervention group also received an rtCGM system to monitor their glucose levels 24 h a day. While controlling for physical activities and GI and GL nutrition knowledge, the results indicated that the rtCGM system further improved body weight, BMI, fat mass, fasting plasma glucose, HbA1c, total cholesterol, HDL cholesterol and LDL cholesterol in the intervention group (p < 0.05). This trial unveils the robustness of the rtCGM where non-diabetic overweight and obese young adults can benefit from this device and utilise it as a management tool for overweight and obesity and a primary prevention tool for type 2 diabetes, as it provides real-time and personalised information on physiological changes.
... Vinegar is the product of acetic acid and is reported to have anti-glycemic effects in either animal or human studies (Johnston and Gaas, 2006). The mechanisms of vinegar are based on improved insulin sensitivity and delayed gastric emptying accompanied with improved glycemic control and reduced body weight (Halima et al, 2017;Khezri et al., 2018;Siddiqui et al., 2018;Shishehbor et al., 2017;Chen et al., 2016;Petsiou et al., 2014). ...
... A systemic review and meta-analysis study show that the consumption of vinegar can decrease postprandial glucose and insulin level (Shishehbor et al., 2017). Samad et al. (2016) reviewed the therapeutic effects of vinegar and shown that daily consumption of vinegar is associated with improvement of chronic disease status such as high blood pressure, hyperlipidemia and obesity. ...
This open-label non-controlled study is to evaluate the effects of black vinegar intake for 8 weeks on the anthropometric measures, cardiometabolic profiles, and insulin sensitivity among impaired fasting glucose adults. 32 subjects (14 males and 18 females) were recruited with the mean age of 56.3 (from 25 to 65). Black vinegar 50 ml was diluted to 500 ml with drinking water and was given to all subjects for 8 weeks. At baseline and 8-week, all study subjects received 75 g of oral glucose tolerance test (OGTT) after 10 h of fasting. Venous blood was collected at 0, 30, 60, 90 and 120 min. Plasma glucose and insulin levels were measured using the glucose oxidase method and radioimmunoassay method. Anthropometric variables, blood pressure and blood lipid profiles were measured using standard methods. The Wilcoxon signed-rank test was used to compare the difference between baseline and after eight weeks. After eight weeks, the body weight and BMI decreased from 68.2 ± 14.4 kg to 67.6 ± 14.2 kg and 26.3 ± 4.5 kg/m2 to 26.0 ± 4.4 kg/m2, respectively, with statistical significance (p < 0.05). Triglyceride level decreased from 152.5 ± 134.7 to 140.6 ± 93.8 mg/dl but without statistical significance. The blood glucose levels at 120 min of OGTT decreased from 178.8 ± 57.0 to 173.7 ± 57.5 mg/dl and the insulin levels at 120 min of OGTT increased from 117.5 ± 74.2 to 126.4 ± 95.9 IU/L but not statistically significant (p > 0.05). There is a slight decrease of body weight and BMI, but no significantly change in blood pressure, lipid profiles, and insulin sensitivity after eight weeks of black vinegar intake among impaired fasting glucose adults. However, further large-scale and longer studies are needed to explore the effects of black vinegar on cardiometabolic profiles and insulin sensitivity. Keywords: Black vinegar, anthropometric measures, lipid profiles, insulin sensitivity, impaired fasting glucose.
... In China, vinegar-soaked raisins are believed to be beneficial to obesity prevention. Meta-analysis research confirmed that dietary vinegar consumption could effectively improve postprandial blood glucose and insulin responses [11], reduce appetite [12], and enhance satiety [13]. However, the combined effect of dried fruits and vinegar on glycemic responses and satiety has not yet been studied. ...
... A previous study showed that vinegar served with white bread attenuated both glycemic and insulin responses and found a dose-response relationship between the glycemic effect and acetic acid content [13]. A meta-analysis confirmed that vinegar ingestion could effectively decrease postprandial glycemic and insulin response in both healthy people and patients with type 2 diabetes [11]. In the present study, DA soaked with vinegar containing 1.5 g of acetic acid achieved a 1.0-mmol/L reduction in the average glucose peak, a 1.1mmol/L reduction of glycemic excursion in 240 minutes, and a 35-point reduction in the GI. ...
This study investigated 2 possible approaches to dietary control of acute postprandial responses to a rice-based meal under equicarbohydrate conditions: (1) a dried apple (DA) preload and (2) co-ingestion of vinegar-soaked DA. We hypothesized that both approaches would counteract hyperglycemia with no negative effect on satiety, possibly explained by an inhibitory effect on digestive enzyme activity and/or the effect of the sugar component of the DA. Fifteen healthy female subjects consumed (1) rice, (2) co-ingestion of DA and rice (DA + R), (3) DA preload and rice (PDA + R), (4) rice with sugar solution (same sugar profile as in DA) preloaded (PSS + R), or (5) co-ingestion of rice with vinegar-soaked DA (VDA + R) in a randomized crossover trial. Acute postprandial glycemic response tests and subjective satiety tests were conducted for each test meal. Compared with rice reference, the PA + R and PSS + R achieved 31.4% and 36.3% reduction of the incremental area under the curve0-120, 24.3% and 27.0% decreases in the average glucose peak, along with 21.6% and 27.0% decreases in glycemic excursion in 240 minutes, whereas the VDA + R resulted 42.4%, 27.0%, and 29.7% reductions in the incremental area under the curve0-120, peak, and glycemic excursion, respectively. The DA-containing meals had no effect or a favorable effect on satiety. The in vitro assay found larger resistant starch and smaller rapid digestible starch fractions in DA + R and VDA + R meals compared to those of the rice reference (P < .001). The result of this study supported the research hypothesis, and the DA-containing meals could be considered as a potential dietary approach for glycemic management.
... ACV's acetic acid improves fat metabolism by enhancing fat oxidation, inhibiting fat synthesis and increasing mitochondrial activity, contributing to weight reduction even without major lifestyle changes. 7 Thus, the metabolic impacts of acetic acid provide a clear mechanistic basis for the substantial reductions in body mass observed in our participants. This body of evidence contextualises our findings, illustrating why ACV might lead to substantial weight loss without major dietary or exercise changes. ...
... Fruit fermentation produces a bioliquid containing various functional molecules such as organic acids, polyphenols, melanoidins, and tetramethylpyrazine (Ousaaid et al., 2021). Although vinegar has various components, the main ingredient is acetic acid (4%-8%; Shishehbor et al., 2017). Moreover, vinegar can be used as an antimicrobial resource (Park et al., 2016). ...
Pomegranate, hawthorn, gilaburu, blackberry, and rosehip vinegar postbiotic solutions (VPS) were produced by traditional methods. The bioactive components of VPS, antioxidant capacity, antimicrobial activities, minimum inhibition concentration (MIC), and minimum bactericidal concentration (MBC) assays were determined. While rosehip VPS has the highest amount of lactic acid, phenolic and flavonoids, gilaburu VPS has the highest butyric acid. The highest antimicrobial activities were observed for hawthorn VPS on C. albicans and S. aureus, for gilaburu VPS on S. poona and S. aureus, for blackberry VPS on C. albicans mold and S. agalactiae, for pomegranate VPS on E. coli and S. agalactiae and for rosehip VPS on C. albicans and S. agalactiae. Moreover, the mortality values were reported as MBCs: hawthorn for S. aureus (94.6% at 0.03 mg mL⁻¹) and S. paratyphii A (94.1% at 0.03 mg mL⁻¹), gilaburu for S. aureus (93.4% at 0.06 mg mL⁻¹) and P. aeruginosa (93.2% at 0.13 mg mL⁻¹), rosehip for S. agalactiace and E. coli (93.7–91.7% at 0.06 mg mL⁻¹), pomegranate for methicillin‐resistant S. aureus (96.0% at 0.5 mg mL⁻¹), and blackberry for S. aureus (91.3% at 0.25 mg mL⁻¹) and P. aeruginosa (92.1% at 0.13 mg mL⁻¹), in addition to an equal mixture of the five VPSs for S. aureus and P. aeruginosa (85.6% at 0.06 mg mL⁻¹). The MICs for VPS were generally found in a 0.5 mg mL⁻¹dilution of each vinegar. Remarkably, common and local fruits can be rich sources of bioactive components without the need for imported products or expensive processing methods or equipment. This study demonstrated that rosehip VPS has the greatest potential as both a nutrient and a natural disinfectant.
... 76 What is more, these effects were relatively consistent, regardless of the diabetes status of the participants. 76 81 This suggested that acid preloading may be a potentially useful strategy to help people attenuate postprandial hyperglycaemia. However, caution should be advised on the potential detrimental effect of consuming highly acidic foods on dental erosion. ...
Type 2 diabetes mellitus is one of the most prevalent health conditions worldwide, affecting millions of individuals and posing significant public health challenges. Understanding the nature of type 2 diabetes, its causes, symptoms and treatments is crucial for managing and preventing its complications. Many different dietary strategies are used by individuals to treat and manage diabetes. This review provides an overview of popular dietary strategies that have evidence for improving long‐term glycaemic control or achieving diabetes remission, as well as strategies that may be useful to reduce postprandial hyperglycaemia, which may be of use in the prevention of diabetes, but also as strategies for those already diagnosed but trying to manage their condition better. Recent clinical trials have provided evidence that in people living with type 2 diabetes who also live with overweight or obesity, using a total diet replacement weight loss programme results in significant and substantial weight loss, and as a result, many people can achieve remission from their diabetes. There has been considerable interest in whether similar effects can be achieved without reliance on formula foods, using real diet approaches. Reduced or low‐carbohydrate diet approaches hold some promise, with observational or preliminary findings suggesting beneficial effects, but evidence from robust trials or systematic reviews of randomized controlled trials is still lacking. The Mediterranean dietary pattern, low in saturated fat and high in monounsaturated fat, also has some potential, with evidence to suggest some people can lose weight and achieve remission using this approach, which may be easier to adhere to longer term than more intensive total diet replacement and low‐carbohydrate strategies. Plant‐based diets that advocate for the elimination of animal‐based and/or animal‐derived foods have increased in popularity. There is evidence from epidemiological studies that people who follow these diets have a lower risk of developing type 2 diabetes, and evidence from trials and systematic reviews of trials that changing to a dietary pattern lower in animal‐based and animal‐derived foods has benefits on glycaemic control and other markers of cardiovascular disease. While these approaches all provide food or nutrient prescriptions, approaches that incorporate periods of fasting do not provide rules on the types of foods that can or cannot be consumed, but rather provide time windows of when to eat. Evidence suggests that these approaches can be as effective in achieving energy restriction and weight loss as approaches that advocate continuous energy restriction, and there is evidence for benefits on glycaemic control independent of weight loss. Finally, popular dietary strategies that may be useful to use or combine to help prevent postprandial hyperglycaemia include reducing the glycaemic index or glycaemic load of the diet, high‐fibre diets, eating foods in a meal in the order vegetables > protein > carbohydrates, preloading or combining acids such as vinegar or lemon juice with meals and engaging in low‐intensity aerobic exercise immediately after meals.
... The highest number of publications was noted in 2018 (n = 44). This fact coincides with studies that report that in the past 20 years there has been an increase in vinegar consumption, especially due to its potential health benefits (Shishehbor et al., 2017). ...
... It is used in the preparation of fish and various seafood as well as pickles in the fruits and vegetables industry. In addition, it improves the sensory properties and preserves the food by giving it acidity [6,7]. On the other hand, vinegar has beneficial effects on health when consumed regularly, which is due to its antimicrobial, antidiabetic, antioxidative, anti obesity and antihypertensive activities. ...
... In our study, acetic acid obviously lowered FBG levels and decreased the duodenal amplitude of contraction, which confirmed our hypothesis that LBPs regulate duodenal contraction via acetic acid to improve glucose homeostasis. It has been demonstrated that acetic acid can improve glucose tolerance and lipid disorders [52,53]; however, these results were not observed in our study, probably due to the dosage of acetic acid. ...
Lycium barbarum polysaccharides (LBPs) have been shown to exert an antiglycemic effect. Emerging evidence suggests that patients with hyperglycemia have a hypercontractility of duodenum, and targeting duodenal contraction of duodenum can be beneficial to glucose metabolism. However, it is unknown whether LBPs can improve glucose metabolism by regulating the hypercontractility of the duodenum. Our aim was to explore the effect of LBPs on duodenal contraction in prediabetic mice and also preliminarily investigate the mechanism. The results showed that LBPs improved glucose homeostasis by decreasing the duodenal amplitude of contraction rather than frequency. Moreover, LBPs ameliorated the gut microbiota composition and the levels of short-chain fatty acids, especially acetic acid, which might bind to the receptor on neurons to regulate the contraction of the duodenum. Acetic acid was hypothesized to play a key role in the above process. Then, acetic acid was determined to exert an antiglycemic effect as expected. In conclusion, LBPs may rely on acetic acid to regulate duodenal contraction to ameliorate glucose metabolism in prediabetic mice, which provides a new therapeutic strategy to treat dysglycemia.
... Third, kombucha has been suggested to contain constituents that reduce starch digestion and reduce net absorbed glucose (51). Kombucha also contains acetic acid, which has been reported to have anti-diabetic properties, although at higher concentrations than the kombucha used in our study (52)(53)(54) (several reports). Furthermore, other studies have reported the absence of an anti-glycemic effect (55). ...
Introduction
Kombucha is a popular fermented tea that has attracted considerable attention due, in part, to its suggested health benefits. Previous results from animal models led us to hypothesize kombucha may reduce blood sugar levels in humans with diabetes. The objective of this pilot clinical study was to evaluate kombucha for its anti-hyperglycemic activities in adults with diabetes mellitus type II.
Methods
The study was organized as a prospective randomized double-blinded crossover study at a single-center urban hospital system. Participants (n = 12) were instructed to consume either a kombucha product or a placebo control (each 240 mL) for 4 weeks. After an 8-week washout period, participants consumed the alternate product. Fasting blood glucose levels were self-determined at baseline and at 1 and 4 weeks during each treatment period. Secondary health outcomes, including overall health, insulin requirement, gut health, skin health, mental health, and vulvovaginal health were measured by questionnaire at the same time points. The kombucha microbiota was assessed by selective culturing and 16S rRNA gene (bacteria) and ITS (fungi) sequencing. Fermentation end products were assessed by HPLC. Statistical significance of changes in fasting blood glucose was determined using paired, two-tailed student’s t-tests.
Results
Kombucha lowered average fasting blood glucose levels at 4 weeks compared to baseline (164 vs. 116 mg/dL, p = 0.035), whereas the placebo did not (162 vs. 141 mg/dL, p = 0.078). The kombucha microbiota, as assessed by cultural enumeration, was mainly comprised of lactic acid bacteria, acetic acid bacteria, and yeast, with each group present at about 10⁶ colony forming units (CFU)/mL. Likewise, 16S rRNA gene sequencing confirmed that lactic acid and acetic acid bacteria were the most abundant bacteria, and ITS sequencing showed Dekkera was the most abundant yeast. The primary fermentation end products were lactic and acetic acids, both less than 1%. Ethanol was present at 1.5%.
Discussion
Although this pilot study was limited by a small sample size, kombucha was associated with reduced blood glucose levels in humans with diabetes. Larger follow-up studies are warranted.
Clinical trial registration
ClinicalTrials.gov, identifier NCT04107207.
... К сожалению, нет и подтверждений пользы от его продолжительного ежедневного употребления. [24,25] Как правильно употреблять яблочный уксус, чтобы избежать побочных эффектов? ...
В статье рассмотрены основные свойства яблочного уксуса и его воздействие на организм человека. Проведен систематический обзор современной специализированной литературы и актуальных научных данных. Указан химический состав и пищевая ценность продукта, рассмотрено использование яблочного уксуса в различных видах медицины и эффективность его применения при различных заболеваниях. Отдельно проанализированы потенциально неблагоприятные эффекты яблочного уксуса на организм человека при определенных медицинских состояниях и заболеваниях.
... Interestingly, it was also discovered that wine vinegar ingestion could improve postprandial glucose levels in patients with type 2 diabetes mellitus when added to a high rather than a low-glycaemic-index meal (Liatis et al. 2010). Furthermore, Shishehbor, Mansoori and Shirani (2017) demonstrated that vinegar intake could improve the postprandial glucose response in both healthy individuals and subjects with glucose metabolism disorders. ...
Nipa palm vinegar has been traditionally used to manage blood glucose levels by diabetic patients in Southeast Asia. This study was designed to evaluate the efficacy of nipa palm vinegar in inhibiting the activity of carbohydrate hydrolyzing enzymes, α-glucosidase, and α-amylase. In vitro spectrophotometric assays were used to evaluate the inhibitory activity of nipa palm activity against α-glucosidase and α-amylase. To confirm the in vitro findings, an oral starch tolerance test in the normoglycemic Sprague Dawley rat was conducted. Acarbose was used as the positive control for both tests. Nipa palm vinegar at a concentration ranging from 4000 to 62.5 mg/mL inhibited the activity of α-glucosidase and α-amylase in a concentration-dependent manner with the respective IC 50 values of 144.50 ± 1.1 mg/mL and 90.30 ± 1.7 mg/mL. It also exerted uncompetitive inhibition against α-glucosidase and competitive inhibition towards α-amylase. In vivo oral starch tolerance test showed a significant (p < 0.05) postprandial glucose-lowering effect of nipa palm vinegar at the doses of 2 mL/kg and 1 mL/kg body weight as compared to the control. In a conclusion, this study demonstrated that nipa palm vinegar suppressed the rise in postprandial glucose levels partly by inhibiting the activity of digestive enzymes. ABSTRAK Cuka nipah telah digunakan secara tradisi dalam mengawal aras glukosa darah oleh pesakit diabetes di Asia Tenggara. Kajian ini menilai keberkesanan cuka nipah dalam merencat aktiviti enzim-enzim hidrolisis karbohidrat iaitu α-glukosidase dan α-amilase. Ujian spektrofotometrik secara in vitro telah digunakan untuk menguji potensi aktiviti perencatan cuka nipah terhadap α-glukosidase dan α-amilase. Bagi mengesahkan penemuan ujian in vitro, ujian toleransi kanji oral secara in vivo pada tikus normoglisemik dijalankan. Keputusan menunjukkan cuka nipah merencat aktiviti α-glukosidase dan α-amilase secara kebergantungan kepekatan dengan nilai IC 50 adalah masing-masing adalah 144.50 ± 1.1 mg/mL dan 90.30 ± 1.7 mg/mL. Cuka nipah juga menunjukkan perencatan tidak kompetitif terhadap α-glukosidase dan perencatan kompetitif terhadap α-amilase. Ujian toleransi kanji oral secara in vivo menunjukkan cuka nipah pada dos 2 mL/kg dan 1 mL/kg berat badan mampu menurunkan aras glukosa postprandial secara signifikan dibandingkan dengan kawalan (p<0.05). Kesimpulannya, kajian ini membuktikan cuka nipah menghalang kenaikan aras glukosa darah postprandial, sebahagiannya dengan merencat aktiviti enzim pencernaan.
... The mechanisms of action for these effects are unclear and are likely to occur through multiple processes that include improvements in gut microbiota and islet beta cell function, inhibition of inflammation and insulin resistance, and reduced damage to the intestinal barrier (8). Recent systematic reviews and meta-analyses on the effects of vinegar on postprandial glucose and insulin levels further suggest the acetic and gluconic acid content of kombucha contribute to its effects (9)(10)(11)(12). ...
Introduction
Kombucha is a complex probiotic beverage made from fermented tea, yet despite extensive historical, anecdotal, and in-vivo evidence for its health benefits, no controlled trials have been published on its effect on humans.
Methods
We conducted a randomised placebo-controlled, cross-over study that examined the Glycemic Index (GI) and Insulin Index (II) responses after a standardised high-GI meal consumed with three different test beverages (soda water, diet lemonade soft drink and an unpasteurised kombucha) in 11 healthy adults. The study was prospectively registered with the Australian New Zealand Clinical Trials Registry ( anzctr.org.au : 12620000460909). Soda water was used as the control beverage. GI or II values were calculated by expressing the 2-h blood glucose or insulin response as a percentage of the response produced by 50 g of glucose dissolved in water.
Results
There was no statistically significant difference in GI or II between the standard meal consumed with soda water (GI: 86 and II: 85) or diet soft drink (GI: 84 and II: 81, ( p = 0.929 for GI and p = 0.374 for II). In contrast, when kombucha was consumed there was a clinically significant reduction in GI and II (GI: 68, p = 0.041 and II: 70, p = 0.041) compared to the meal consumed with soda water.
Discussion
These results suggest live kombucha can produce reductions in acute postprandial hyperglycemia. Further studies examining the mechanisms and potential therapeutic benefits of kombucha are warranted.
... The elevation of T2DM incidence in Asians has led us to re-recognize the importance of the diet-based prevention of extremely high postprandial blood glucose. Therefore, the identification of novel functional Asian foods regulating blood glucose levels has emerged as an important project of research in T2DM (Brand-Miller et al. 2012;Gunnerud et al. 2012;Shishehbor et al. 2017). Many natural products such as Asian apricots and their processed foods have been taken as daily foods and folk medicine in many Asian countries including Japan and also widely consumed throughout the world because of their possible health benefits (Hao da and Xiao 2014; Wu et al. 2018;Aoi et al. 2020;Aoi et al. 2021;Chakraborty and Roy 2021;Georgiev et al. 2021;Rambaran and Nordström 2021;Kahksha et al. 2022;Ma et al. 2022;Pan et al. 2022;Zahedipour et al. 2022;Zhu et al. 2022). ...
The present study tried to clarify if mumefural would prevent hyperglycemia, one of the typical symptoms of type 2 diabetes mellitus (T2DM), since mumefural is an extract from Japanese apricots preventing hyperglycemia. To clarify if mumefural would prevent T2DM pathogenesis, we used Otsuka Long-Evans Tokushima fatty (OLETF) rats, T2DM model. Mumefural diminished hyperglycemia, HOMA-IR and plasma triglyceride concentration in OLETF rats under fasting conditions. In addition, mumefural elevated protein expression of sodium-coupled monocarboxylate transporter 1 (SMCT1) in the distal colon participating in absorption of weak organic acids, which behave as bases but not acids after absorption into the body. Mumefural also increased the interstitial fluid pH around the brain hippocampus lowered in OLETF rats compared with non-T2DM LETO rats used as control for OLETF rats. Amyloid-beta accumulation in the brain decreased in accordance with the pH elevation. On the one hand, mumefural didn't affect plasma concentrations of glucagon, GLP-1, GIP or PYY under fasting conditions. Taken together, these observations indicate that: 1) mumefural would be a useful functional food improving hyperglycemia, insulin resistance and the lowered interstitial fluid pH in T2DM; 2) the interstitial fluid pH would be one of key factors influencing the accumulation of amyloid-beta.
... All the meta-analyses of vinegar consumption found that glycaemic control was improved in individuals with IGT or T2DM, including: FBG; [42,44] HbA1c; [40,42] and acute glucose response/ postprandial glucose and insulin. [41,45] Cheng et al. [42] also found statistically significant improvement in LDL-C and TC levels. However, there was substantial heterogeneity reported across studies within each meta-. ...
Objective To assess whether botanical fermented food (BFF) consumption has an impact on cardiometabolic biomarkers or gut microbiota in adults with obesity, metabolic syndrome (MetS) or type 2 diabetes mellitus (T2DM).
Design Systematic review. Data sources Embase, MEDLINE, Cochrane CENTRAL and Google Scholar were searched with no language limits, from inception to August 31, 2022.
Eligibility criteria. Randomised controlled trials (RCTs) investigating the effects of BFFs on glucose, lipid, anthropometric, inflammatory and gut microbial parameters, in participants with obesity, MetS or T2DM.
Data extraction and synthesis. Two independent reviewers screened 6873 abstracts and extracted relevant data. Risk of bias (ROB) was assessed using the Cochrane Collaborations ROB2 tool. A qualitative, narrative synthesis was produced.
Results. The final review included 26 RCTs, with 31 reports published between 2001 and 2022. Significant (p<0.05) within-group and between-group changes in cardiometabolic outcome means were reported in 23 and 19 studies, respectively. Gut microbiota composition was assessed in four studies, with two finding significant between-group differences. No significant difference between groups of any measured outcomes was observed in five studies. There were 14 studies at low ROB; nine were of some concern; and two were at high ROB.
Conclusion. In 77% of included studies, BFF consumption by participants with obesity, MetS or T2DM led to significant improvements in some cardiometabolic outcomes, including fasting blood glucose, lipid profile, blood pressure, waist circumference, body fat percentage, and C-reactive protein. BFF consumption increased the abundance of beneficial gut bacteria, such as Bifidobacterium and Lactobacillus, whilst reducing Bacteroides. To determine the clinical significance of BFFs as therapeutic dietary adjuncts, their safety and tolerability must be balanced with the limited power and magnitude of these preliminary findings.
Ethics. Ethical approval was not required as primary data was not collected.
PROSPERO registration number. CRD42018117766
... In the study by Ostman et al., a 35% decrease in GI was observed when 18 mmol acetic acid (equivalent to 20 g of vinegar) was combined with high GI foods, such as white bread (37). Meanwhile, Liljeberg et al. observed an 11% decrease in the GI when the vinegar was administered in the form of a vinaigrette, including water and olive oil (8 g), a fact that may help explain this more significant drop in the glycemic response (37,38). ...
Diet plays a critical role in the management of many chronic diseases. It is well known that individuals with type 2 diabetes (T2D) need to pay close attention to foods rich in carbohydrates to better manage their blood sugar. Usually, individuals are told to increase their dietary fiber intake which is associated with better glycemic control and limit their overall carbohydrate consumption. However, there are many other cooking strategies available to reduce the glycemic response to meals rich in carbohydrates and with a high glycemic index, such as adding fats, proteins, or vinegar, modifying the cooking or preparation processes, and even the selection and storage of foods consumed. The aim of the present narrative review is to summarize some of these existing strategies applied to the cooking process and their ability to modulate glycemic response to meals in individuals with T2D.
... Studies on spicy food found that spiciness played a benefcial role in cancer, obesity, and CVD, and the habitual consumption of spicy foods was inversely associated with mortality [15,16]. Vinegar also protected health by attenuating postprandial glucose and insulin responses and reducing body weight [17,18]. ...
Background:
Dietary modulation is a primary lifestyle approach for reducing the risk of hypertension. However, evidence of the potential role that a dietary taste preference plays in the risk of hypertension remains limited.
Methods:
A cross-sectional analysis was conducted based on the Shaanxi baseline survey of the Regional Ethnic Cohort Study. We used self-reported salt consumption and intensity preferences for sourness and spiciness to calculate the taste preference score, which was categorized into bland, moderate, and strong. A generalized linear mixed model and quantile regression were performed to estimate associations between taste preferences and hypertension/blood pressure.
Results:
Among 27,233 adults, 72.2% preferred a moderate taste and 21.4% preferred a strong taste. Compared with a bland taste, a stronger taste preference might be associated with a higher risk of hypertension (adjusted OR for a moderate taste = 1.25, 95% CI: 1.06, 1.49; adjusted OR for a strong taste = 1.41, 95% CI: 1.15, 1.71; P trend = 0.002), especially in females (adjusted OR for a moderate taste = 1.43, 95% CI: 1.24, 1.66; adjusted OR for a strong taste = 1.55, 95% CI: 1.32, 1.83; P trend < 0.001). Quantile regression showed that the taste preference was positively associated with diastolic blood pressure (DBP) (P 5-P 80) in females, with an average increase of 3.31 mmHg for a strong taste (β = 3.31, P < 0.001) and 1.77 mmHg for a moderate taste (β = 1.77, P = 0.008).
Conclusions:
A preference for stronger multitastes of salty, sour, and spicy might be associated with a higher risk of hypertension, especially in females. This relationship possibly occurs through increasing DBP. Dietary modulation with the promotion of a bland taste is encouraged.
... While some studies suggest a positive effect of vinegar consumption on these risk factors [10,13], these effects were not observed in other studies [14,15]. Amid conflicting evidence, a meta-analysis reported that vinegar consumption significantly reduced postprandial insulin and glucose levels compared with controls [16]. However, the effects of vinegar consumption on glucose metabolism, lipid profile, and anthropometric indicators of obesity, which collectively represent cardiometabolic risk factors, deserve further attention. ...
Introduction
Studies that investigated the association between the consumption of vinegar and various cardiometabolic parameters have yielded conflicting results. In this work, we investigated the effects of vinegar consumption on cardiometabolic risk factors using a meta-analysis.
Methods
Relevant studies were identified using four databases (Scopus, PubMed/MEDLINE, Embase, and Web of Science) up to January 2022. Of the 2806 articles from the initial search, 11 RCTs with 12 treatment arms were included in the meta-analysis. The RCTs focused on both healthy individuals and individuals with cardiometabolic disorders.
Results
Consumption of vinegar was associated with significant reductions in fasting blood glucose (WMD: -9.36 mg/dL, 95% CI: -14.82, -3.91) and glycated hemoglobin (WMD: -0.67, 95% CI: -1.36, - 0.01). In terms of lipid profile, there was a significant reduction in total cholesterol (WMD: -18.87 mg/dl, 95% CI: -34.44, -3.29) and low-density lipoprotein cholesterol (WMD: -21.37 mg/dl, 95% CI: -37.54, -5.20), but non-significant reductions in high-density lipoprotein cholesterol and triglycerides were noted, although the latter reduction was of clinical significance (WMD: -21.47 mg/dl, 95% CI: -49.72, 6.77). In addition, no significant changes in fat mass and waist circumference were observed, while significant reductions in body mass index (WMD: -0.39 kg/m², 95% CI: -0.74, -0.04, p = 0.028) and body weight (WMD: -0.73 kg, 95% CI: -1.45, -0.01) were noted with dubious clinical relevance.
Conclusion
In conclusion, the consumption of vinegar may have beneficial effects on some glycemic and lipid indices and could be considered as an intervention for weight loss.
... The second proposed mechanism for appetite suppression is based on lowering glycemic index (GI). This effect was confirmed by meta-analyses, and the proposed mechanisms include delayed GER, slower glucose absorption, increased glucose uptake by skeletal muscle, and inhibition of hepatic gluconeogenesis (6,44). Several studies found that vinegar concurrently reduced appetite and glycemic/insulinemic response (15,16,18). ...
Research suggests that the active ingredient in vinegar, acetic acid, may reduce appetite, thereby reducing energy consumption. This article aims to assess the effect of vinegar or acetic acid on appetite measures and subsequent food intake in humans. This was conducted as a systematic literature review adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. All participants were considered, regardless of age or health status. A search using MedLine (Ovid), PubMed, CINAHL Plus, Web of Science, and Cochrane Library between January and April 2021 resulted in 12 studies. Outcomes included appetite, measured using an appetite rating scale or visual analog scale; satiation, measured as food intake of intervention meal; and satiety, measured as the amount of food intake after vinegar or acetic acid consumption. Some short-term interventions indicate that vinegar containing at least 24.6 mmol acetic acid, when consumed alongside a meal containing solid foods, acutely suppresses appetite up to 120 min postprandially as well as ad libitum food intake 3 and 24 h after vinegar consumption. However, longer exposure vinegar interventions suggest that vinegar does not affect overall energy intake. Further research is needed to determine whether oral vinegar consumption may lead to long-term appetite reduction, decrease energy intake, and aid in weight loss.
... Vinegar is not only used as a seasoning to add sour flavor but also to preserve food. The health benefits of vinegar have been reported, including anti-diabetic, anti-tumor, anti-obesity, antihypertensive, antiinflammatory, and cholesterol metabolism-regulating effects [4,5]. Acetic acid (>4%), the main component of vinegar, has been shown to have antihypertensive effects in animal studies [6]. ...
Objective
Vinegar has been reported to have a hypotensive effect. We aimed to investigate the relationship between the consumption of vinegar-based side dishes and blood pressure.
Research Methods & Procedures
This cross-sectional study included 746 individuals (257 men and 489 women) aged ≥40 years from Tarumizu, Kagoshima, Japan. Nutrient intake was estimated based on the brief-type self-administered diet history questionnaire. The intake frequency of vinegar-based side dishes (Sunomono and pickles) was determined using a self-administered diet history questionnaire. Participants who did not consume vinegar-based side dishes for a month were defined as having no Sunomono or pickle eating habit. Blood pressure was categorized into four groups according to the Japanese Society of Hypertension Guidelines for the Management of Hypertension. The association between the intake of vinegar-based side dishes and blood pressure categories was analyzed using ordinal logistic regression analysis adjusted for age, body mass index, smoking history, excessive alcohol intake, living situation, energy intake, protein intake, sodium intake, potassium intake, and seaweed intake.
Results
Approximately 13.6% men and 6.1% women had no Sunomono eating habits. In men, eating Sunomono, but not pickles, was significantly related to blood pressure categories (estimate, −0.702; 95% CI, −1.122 to −0.310), whereas more frequent consumption of Sunomono did not show an improvement in the blood pressure category. The relationship between eating Sunomono and blood pressure categories was not recognized in women.
Conclusion
This was the first study assessing the association between consumption of vinegar-based side dishes and blood pressure categories. We highlighted the effect of Sunomono consumption on blood pressure categories in men. Consumption of Sunomono may improve blood pressure in men.
... Supplementation with natural dietary antioxidants has become an essential strategy in the treatment of diet-related diseases, reducing oxidative stress, preventing age-related diseases and maintaining homeostasis [16]. Hence, natural vinegar has not only been used as a condiment and food preservative for thousands of years [18], but it is also used in traditional folk medicine [19] and beauty products [20] in modern times. Nowadays, the consumption of natural vinegar has been increased due to its health benefits. ...
Functional fermented fruit drinks are known worldwide for their health-promoting potential. Black wolfberry (BW) has high nutritional value, and its relative product development can be enriched through fermentation technology, so that its market might be broadened. Total acid, sugars, proteins, enzymes, anthocyanins, flavonoids, polyphenols, organic acids and DPPH free radical scavenging ability (DPPH) were tracked and determined by colorimetric method and HPLC during spontaneous fermentation of BW vinegar. The antioxidant capacity in vitro of BW vinegar was evaluated based on the dynamics of antioxidant contents and DPPH. The results showed that total acid continuously increased during fermentation, yet total sugar and reducing sugar shared a similar decreasing trend. The composition of samples differed in terms of total anthocyanins, total flavonoid, total polyphenol, total protein, superoxide dismutase (SOD), amylase, organic acids and DPPH through spontaneous fermentation. Functional compounds including total polyphenol, total flavonoid and three organic acids (γ-aminobutyric acid, lactic acid and gallic acid) played the main roles in antioxidation. Unexpectedly, SOD and ascorbic acid as antioxidants did not correlate with DPPH, but they were rich in the final products at 754.35 U/mL and 3.39 mg/mL, respectively. Generally , the quality of BW vinegar has been improved based on analyzing dynamics on functional compounds, organic acids and antioxidant capacity, which proves that BW vinegar obtained by spontaneous fermentation should be a potential source of fermented food with antioxidant effects for consumers.
... with a recent meta-analysis (70) in which all participants were pooled and vinegar was shown to reduce glucose and insulin concentrations. This could bode well for future treatments to halt the progression of glycemic deterioration. ...
Background
Non-communicable disease development is related to impairments in glycaemic and insulinemic response, which can be modulated by fiber intake. Fiber's beneficial effect upon metabolic health can be partially attributed to the production of short-chain fatty acids (SCFAs) via microbial fermentation of fiber in the gastrointestinal tract.
Objective
We aimed to determine the effect of the SCFAs, acetate, propionate, and butyrate on glycemic control in humans.
Methods
CENTRAL, Embase, PubMed, Scopus and Web of Science databases were searched from inception to the 07/12/2021. Papers were included if they reported a randomized, controlled trial measuring glucose and/or insulin compared to a placebo in adults. Studies were categorized by the type of SCFA and intervention duration. Random effects meta-analyses were performed for glucose and insulin for those subject categories with ≥3 studies, or a narrative review was performed.
Results
We identified 43 eligible papers, with 46 studies within those records (n = 913), 44 studies were included in the meta-analysis. Vinegar intake decreased acute glucose response, standard mean difference (SMD) and (95% CI) –0.53 (–0.92, –0.14) (n = 67) in individuals with impaired glucose tolerance or type 2 diabetes and in healthy (SMD) –0.27 (–0.54, 0.00) (n = 186). The meta-analyses for acute acetate as well as acute and chronic propionate studies had no significant effect.
Conclusions
Vinegar decreased glucose response acutely in healthy and non-healthy. Acetate, propionate, butyrate, and mixed SCFAs had no effect on blood glucose and insulin in humans. Significant heterogeneity, risk of bias, and publication bias were identified in several study categories, including acute vinegar glucose response. As evidence was very uncertain, caution is urged when interpreting these results. Further high-quality research is required to determine the effect of SCFAs on glycemic control.
... Metaanaliza przeprowadzona przez F. Shishehbor i wsp. [74] dotycząca wpływu konsumpcji różnych octów owocowych na organizm człowieka wskazała, iż doustna suplementacja octem może nieść pozytywny efekt na stężenie glukozy i insuliny po posiłku, zarówno u osób zdrowych, jak i z zaburzeniami glikemii, oraz może być stosowana jako środek wspomagający kontrolę glikemii. ...
Introduction and objective
Vinegar is a fermented product that is widespread worldwide. It is used primarily as a seasoning to enrich the taste of dishes and to solidify food in the form of marinades. Vinegar may be the source of many compounds exerting a positive effect on the human body. The aim of the study is to present various types of vinegars produced from grape fruit, as well as their health properties.
Review methods
A systematic review of research was conducted using electronic databases such as PubMed, Elsevier and Google Scholar.
Brief description of the state of knowledge
Fruit vinegars are a rich source of vitamins, minerals, organic acids and polyphenolic compounds. The content of these compounds makes vinegars a product with a positive influence on the human organism. Due to the high content of antioxidant compounds, vinegars can be used as adjuncts in the treatment of free radical diseases, such as cardiovascular diseases. The composition and quality of the final product depends on the production method and the microorganisms involved in the fermentation process. Grape vinegars have a beneficial effect on carbohydrate metabolism, reducing the level of fasting glucose and haemoglobin A1c in blood, as well as postprandial glycaemia. Research show that grape vinegars also have a positive effect on the lipid profile by reducing the concentration of total cholesterol and its LDL fraction.
Conclusions
Grape vinegars are a rich source of many bioactive compounds, therefore, they can be used in the treatment of certain diseases, mainly those related to free radicals. The content of individual compounds in grape vinegars is highly diversified, and their composition is influenced both by the vinegar production process and the grape variety used.
... Antioxidant [6], anti-diabetic [7], anti-obesity [8], anti-hypertensive [9], and cholesterollowering effects [10] have been reported as beneficial health effects of vinegar. For instance, Budak and Guzel-Seydim reported that the oxygen radical absorbance capacity and Trolox equivalent antioxidant capacity of traditional vinegar were higher than those of commercial vinegar [6]. ...
Various types of vinegars have been developed as interest in their health benefits has increased. In this study, we prepared Jeju citrus blended vinegars (CBVs) by mixing premature mandarin vinegar and mandarin vinegar, with mandarin vinegar used as a control. The physicochemical properties of the vinegars, including pH, total acidity, and sugar content was determined. Moreover, antioxidant, anti-obesity, and anti-aging activities of the vinegars were investigated. Physicochemical analysis revealed that the CBVs had a pH similar to that of mandarin vinegar, whereas CBVs with relatively high premature mandarin vinegar content showed higher acidity and lower sugar content (p < 0.05). Moreover, the antioxidant activities and phenol contents of CBVs were significantly higher than those of mandarin vinegar (p < 0.05). Meanwhile, CBVs showed significantly decreased intracellular triglyceride, lipid accumulation, and anti-obesity related gene levels (p < 0.05), thereby highlighting their anti-obesity activity. In addition, CBVs showed anti-aging activity by increasing cell viability and cell lifespan, while decreasing the expression of senescence-related genes under H2O2-induced oxidative stress. Therefore, CBVs may be useful as a functional food with antioxidant, anti-obesity, and anti-aging effects in various food fields.
... chudnutie/dieta-tento-tyzden/jablcny-ocot-naozaj-roztopi-tuk-potvrdili-ajvedci.html). It reduces the concentration of glucose and insulin in blood, especially after meals high in carbohydrates (Liljeberg and Björck, 1998, Fushimi et al., 2005, Johnston and Buller, 2005, Sakakibara et al., 2006, Petsiou et al., 2014, Russell et al., 2016, Shishehbor et al., 2017, Siddiqui et al., 2018. Therefore, it is considered a prospective natural treatment against diabetes (Russell et al., 2016, Yamashita et al., 2016, Siddiqui, 2018. ...
... It reduces the concentration of glucose and insulin in blood, especially after meals high in carbohydrates [8][9][10][11][12][13][14][15][16]. Therefore, it is considered a prospective natural treatment against diabetes [13,15,17]. ...
This non-systematic review outlines the current knowledge concerning provenance, chemical composition and properties of apple cider vinegar, its general health effects, as well as the currently available knowledge concerning its action on fat storage, physiological mechanisms of its effects, as well as its safety and recommended dosage for treatment of obesity.
... Vinegars have been used for thousand years as a condiment and food preservative [8]. They have been also used in traditional folk medicine for lowering blood pressure and blood sugar levels, stimulating the digestive system and appetite [9], and also as a beauty product [10]. Grape vinegars are also considered as a functional food, i.e. providing biologically active ingredients with health benefits related to the prevention of chronic diseases [11]. ...
Fruit vinegars are widely used as a spice and food preservative. They are considered as functional food, containing many bioactive compounds with pro-health benefits. Grape vinegars can be also a source of mineral compounds. Their quantity and diversity can be determined by environmental factors and growing conditions, such as temperature, mineral composition of the soil, heavy metal contamination, sunlight availability as well as grape variety and fruit ripeness stage. The aim of the study was to determine the content of minerals in homemade grape vinegars, obtained by spontaneous fermentation. Five different grape ( Vitis vinifera L.) varieties were used in the study (Cabernet Cortis, Johanniter, Solaris, Souvignier gris and Prior). Moreover, the effect of sugar addition in the fermentation process on the mineral content was examined. The mineral content was determined using the ICP-OES method. Among the analysed samples, potassium was the most abundant element (936.07–1472.3 mg/L of vinegar). Comparative analysis showed that the content of Ca, Fe and Cr was significantly higher in vinegars prepared from red varieties than in white-coloured ones. In turn, vinegars prepared from white grape varieties contained statistically significantly higher content of potassium. Vinegar colour did not have a significant influence on the content of the remaining elements included in the analysis. Furthermore, statistical analysis did not reveal any significant differences in the content of the analysed minerals in any of the grape varieties used between the samples with and without sugar addition.
... The complexity of postprandial glucose patterns and the effects of dietary fat, protein, and glycemic index on acute postprandial glucose control in type 1 diabetes has been deeply discussed (Bell et al., 2015). Other dietary factors, such as vinegar, have been also reported to impact postprandial glucose and insulin levels (Shishehbor et al., 2017). The Roux-en-Y gastric bypass surgery which is usually take as a modality to improve glucose control in patients with type 2 diabetes had been reported to develop a life-threatening complication of hyperinsulinemic hypoglycemia (Honka and Salehi, 2019). ...
Neurons in the trigeminal mesencephalic nucleus (Vme) have axons that branch peripherally to innervate the orofacial region and project centrally to several motor nuclei in brainstem. The dorsal motor nucleus of vagus nerve (DMV) resides in the brainstem and takes a role in visceral motor function such as pancreatic exocrine secretion. The present study aimed to demonstrate the presence of Vme–DMV circuit, activation of which would elicit a trigeminal neuroendocrine response. A masticatory dysfunctional animal model termed unilateral anterior crossbite (UAC) model created by disturbing the dental occlusion was used. Cholera toxin B subunit (CTb) was injected into the inferior alveolar nerve of rats to help identify the central axon terminals of Vme neurons around the choline acetyltransferase (ChAT) positive motor neurons in the DMV. The level of vesicular glutamate transporter 1 (VGLUT1) expressed in DMV, the level of acetylcholinesterase (AChE) expressed in pancreas, the level of glucagon and insulin expression in islets and serum, and the blood glucose level were detected and compared between UAC and the age matched sham-operation control mice. Data indicated that compared with the controls, there were more CTb/VGLUT1 double labeled axon endings around the ChAT positive neurons in the DMV of UAC groups. Mice in UAC group expressed a higher VGLUT1 protein level in DMV, AChE protein level in pancreas, glucagon and insulin level in islet and serum, and higher postprandial blood glucose level, but lower fasting blood glucose level. All these were reversed at 15-weeks when UAC cessation was performed from 11-weeks (all, P < 0.05). Our findings demonstrated Vme–DMV circuit via which the aberrant occlusion elicited a trigeminal neuroendocrine response such as alteration in the postprandial blood glucose level. Dental occlusion is proposed as a potential therapeutic target for reversing the increased postprandial glucose level.
... Vinegar ingestion at mealtime alters postprandial glucose excursions, and recent reviews and meta-analyses suggest that vinegar may be a useful adjunct therapy for managing postprandial glycemia [3][4][5]. e latter metaanalysis pooled data from 11 trials and demonstrated a significant mean reduction in postprandial glycemia for the vinegar treatment compared to the control treatment (SMD � −0.60, 95% CI −1.08 to −0.11, p � 0.01). Although the mechanisms of action are uncertain, the defining ingredient of vinegars, acetic acid, when consumed at mealtime, appears to interact with disaccharidases in the small intestine to slow glucose entry into blood, to decrease the rate of gastric emptying, and/or to hasten blood glucose uptake into skeletal muscles [3,[6][7][8]. ...
Objective:
Research evidence suggests that vinegar may effectively reduce postprandial glucose in both healthy adults and those with type 2 diabetes. There is heightened consumer interest in commercially available vinegar tablets; however, it is not known whether these products lower postprandial glycemia to the same extent as liquid vinegar. This crossover trial examined the impact of liquid vinegar versus commercial vinegar tablet ingestion at the start of a meal on the 60-minute glucose excursion postmeal in healthy adults.
Methods:
Twelve young men and women (22.6 ± 0.6 y; 21.2 ± 1.2 kg/m2) completed this 4-arm Latin square crossover trial. Testing was separated by one week and consisted of a test meal (64 g carbohydrate) consumed immediately following one of the four oral treatments: CON, 60 g water (control treatment); VIN, 25 g liquid vinegar (5% acidity; 1.25 g acetic acid) diluted with 35 g water; PILL, four vinegar tablets (1.50 g acetic acid) swallowed whole with 60 g water; and PILL-c, four crushed vinegar tablets dissolved in 60 g water. Capillary blood glucose was tested in the fasted state and at 30 and 60 minutes postmeal.
Results:
The 60-minute glucose excursion varied significantly by treatment (iAUC: 4.9 ± 0.6, 3.4 ± 0.4, 4.9 ± 0.6, and 4.1 ± 0.5 mmol˖h/l for CON, VIN, PILL, and PILL-c, respectively; F (3, 33) = 3.037, p = 0.043; repeated measures ANOVA). Post hoc analysis revealed a 31% reduction in the glucose postmeal excursion for VIN in comparison to CON and PILL (p = 0.040 and p = 0.049, respectively).
Conclusions:
These data suggest that commercial vinegar tablets taken whole at mealtime are not as effective as liquid vinegar for reducing the postmeal glucose excursion in young, healthy adults.
... Although this property has not been extensively investigated, beneficial positive correlations between its consumption and blood pressure, stomach pH, intracellular antioxidant activity, free radical scavenging activity, and bactericidal properties have been observed. 11,12 However, the corpulent pulp of A. othonianum has not been used before for making vinegar. ...
BACKGROUND
Anacardium othonianum Rizzini is a native Cerrado fruit, recently described in the literature. Its use is restricted to its native region and there is a lack of studies regarding production of vinegar from the pulp. This work aims to investigate the production of A. othonianum Rizzini vinegar using submerged fermentation.
RESULTS
The density, alcohol content, proximal composition, pH, color coordinates, and chromatographic profile of the volatile compounds were analyzed in the slurry, fermented juice, and vinegar produced from the corpulent parts of A. othonianum Rizz. Sensory acceptance and willingness to pay were also assessed with vinegar at 4% and 6% of total acidity. The results indicated compliance with European legislation and the presence of volatile compounds such as carbon dioxide, acetic acid, ethanol, and acetaldehyde in the analyzed vinegars. Our results indicate the potential of vinegar production from A. othonianum, with 74% and 86% willingness to pay.
CONCLUSIONS
The process of transformation of the fruit pulp into new products can contribute to fruit valorization and consequent preservation of the plant in the Cerrado biome. To the best of our knowledge, this is the first report of volatile compounds and minerals in A. othonianum Rizz. slurry. Our observations can be used as a basis for future studies regarding the preparation of vinegars from this species and for investigating their application in cooking and guiding consumer perception. © 2020 Society of Chemical Industry
... El vinagre atenuó la glucemia posprandial en un 20% en comparación con el placebo. Además, Shishehbor, Mansoori y Shirani (14) concluyeron que el vinagre puede ser efectivo para reducir los niveles de glucosa e insulina posprandiales. Sin embargo, es importante destacar que faltan estudios en humanos a más largo plazo en los que se investigue el papel del vinagre en la fisiología del huésped, la salud metabólica y cardiovascular. ...
... El vinagre atenuó la glucemia posprandial en un 20% en comparación con el placebo. Además, Shishehbor, Mansoori y Shirani (14) concluyeron que el vinagre puede ser efectivo para reducir los niveles de glucosa e insulina posprandiales. Sin embargo, es importante destacar que faltan estudios en humanos a más largo plazo en los que se investigue el papel del vinagre en la fisiología del huésped, la salud metabólica y cardiovascular. ...
RESUMEN El objetivo del estudio es analizar la concentración de ácido acético de seis marcas de vinagre de manzana comercializados en la ciudad de Chiclayo, Lambayeque-Perú, 2019. El enfoque es cuantitativo, experimental. Se realizaron titulaciones ácido-base para determinar las concentraciones de ácido acético en seis marcas de vinagre de manzana, considerando cinco repeticiones para minimizar el error de medición. Los resultados muestran que solo las marcas 1 y 5 se encuentran dentro del límite mínimo establecido de la concentración de ácido acético (mayor al 5 %). Por otro lado, las marcas 2, 3, 4 y 6 se hallan muy por debajo de dicho límite mínimo establecido para considerarse como vinagres. Palabras clave: Vinagre de manzana; ácido acético; titulación ácido-base. ABSTRACT The objective of the study is to analyze the concentration of acetic acid of six brands of apple cider vinegar commercialized in the city of Chiclayo, Lambayeque-Peru, 2019. The approach is quantitative, experimental. Acid-base titrations were performed to determine acetic acid concentrations in six brands of apple cider vinegar, considering five repetitions to minimize measurement error. The results show that only brands 1 and 5 are within the minimum established limit of acetic acid concentration (greater than 5%). On the other hand, brands 2, 3, 4 and 6 are well below said minimum limit established to be considered as vinegars. INTRODUCCIÓN La Organización de las Naciones Unidas para la Agricultura y la Alimentación (FAO) define al vinagre como un líquido para el consumo humano, producido a partir de materias primas agrícolas que pasan por los procesos de fermentación alcohólica y acética (1). El vinagre es un producto químico que consiste en una solución acuosa de ácido acético, con una concentración del ácido entre 4 y 8% en masa; su cla-sificación depende de la materia prima utilizada para su elaboración, y un tipo es el vinagre de manzana o sidra (2). El Real Decreto 661/2012 del Ministerio de la Presidencia establece la norma de calidad para la elaboración y la co-mercialización de los vinagres, dictando que deben contener alrededor de un 5% de ácido acético (3). Sin embargo, en su mayoría, los vinagres que se consumen no detallan en el etiquetado la concentración de ácido acético que tienen. Sobre todo, esto ocurre con los llamados "productos naturales", como es el caso con el vinagre de manzana. Actualmente, se usa descontroladamente para intentar bajar de peso. Para Zeratsky (4), es poco probable que el vinagre de manzana tenga algún efecto en perder peso; pero los defensores del vinagre de manzana afirman que tiene numerosos beneficios para la salud y que beber una pequeña cantidad o tomar un suplemento antes de las comidas ayuda a reducir el apetito y quemar grasas, aunque hay poco respaldo científico para estas afirmaciones. Los estudios sobre el uso del vinagre de manzana para perder peso no siempre han demostrado una pérdida de peso sig-nificativa y sostenible en diversos grupos de personas. Aunque el uso ocasional del vinagre de manzana es seguro para la mayoría de las personas, conlleva algunos riesgos como irritar la garganta si se bebe a menudo o en grandes
... Nowadays, one of the most popular vinegars in the contemporary natural health community is apple vinegar (AV), which had been assigned many and different health benefits, such as weight loss, laxative properties, blood glucose level lowering effects, and reducing the risk of heart disease. However, the effects of AV are uncertain owing to the absence of convincing scientific evidence from clinical trials [8,9]. The effect from AV on constipation is not investigated in clinical trials but in Folk medicine it is claimed to be useful (https://www.coloncareclinic.com.au/ ...
Purpose
Clozapine is one of the drugs that cause the highest level of weight gain. Additionally, obese patients are at higher risk of developing various physical co-morbidities, such as type 2 diabetes and cardiovascular diseases. Forty-nine percent of patients on clozapine suffer from constipation. Apple vinegar (AV) had been assigned health benefits, such as weight loss, laxative properties, blood glucose lowering effects, and reducing the risk of heart disease. Our hypothesis was that AV would lower the mean glycated haemoglobin level and reduce the level of constipation.
Material and methods
Pilot intervention study with a 12-week follow-up. All patients receiving clozapine treatment for schizophrenia at one outpatient clinic were eligible for inclusion. Intervention: Ten millilitres of AV diluted in 200 ml drinking water with breakfast and dinner.
Results
Forty patients were suitable for inclusion and nine completed the intervention. Women had much higher-than-recommended body mass index. Scores for constipation were high. The reduction in constipation was of clinical interest (2.6 (p = 0.017)). However, there were no statistically significant differences in glycated haemoglobin, cholesterol, HDL, LDL or triglyceride levels. Patients with problems of constipation prior to the intervention experienced much better bowel habits and relief of their constipation.
Conclusion
AV lower the constipation problems faced by patients with schizophrenia treated with clozapine. Further research, repeating this pilot study with a meaningfully larger sample size and randomized with placebo, is needed.
... Therefore, we aimed to comprehensively examine the effects of acetic acid intake on fatigue among the general working population who do not exercise regularly and may feel a decline in physical fitness. It has been shown that continuous intake of acetic acid is effective in promoting lipid metabolism 7,8) , improving sugar metabolism 7,9) , and increasing blood flow 10,11) , and it is suggested that intake of acetic acid may promote energy production in the body. We hypothesized that these effects might contribute to the recovery of physical fatigue. ...
In this study, healthy participants aged 30 to 45 years, who do not exercise regularly, were administered black vinegar beverages (containing acetic acid) daily for 7 days and assessed for feelings of physical fatigue following exercise. The study was a randomized, double-blind, placebo-controlled crossover study. The evaluation was conducted mainly using the Visual Analog Scale (VAS), which assesses feelings of physical fatigue, to measure levels of serum creatine kinase (CK). Feelings of fatigue were determined using the VAS with an ergometer before, immediately, and 30 and 60 min after exercise, as well as at bedtime, and the following morning after awaking. Our results showed that 7 days of test beverage (containing 666 mg acetic acid) intake significantly decreased feelings of physical fatigue 30 min following exercise and at bedtime, compared to intake of the placebo beverage (containing 54.8 mg acetic acid). Furthermore, in the test beverage condition, feelings of shoulder stiffness were significantly decreased at bedtime on the day of exercise and the following morning. However, the test beverage had no significant effects on subjective feelings of fatigue or pain in the leg muscles or levels of serum CK after exercise. Our findings suggested that acetic acid may contribute to a more rapid recovery of physical fatigue after exercise.
... 52,53 Food groups and components with demonstrated benefits include fiber, monounsaturated fatty acids, fruits, vegetables, and others. 51 Eating order (with protein consumed earlier) 54 and vinegar consumption with a meal 55 have also demonstrated benefits. Specific foods that have shown promise include garlic, onions, 56 nuts, 57 turmeric, 58 cinnamon, 48 fenugreek, 59 and a number of other spices. ...
There is growing awareness of the complex link between nutrition and skin. In the last few decades, our understanding of this link has grown significantly with research findings from multiple laboratory, animal, and human studies. From the impact of diet on clinical features of aging skin, to documentation of the biochemical and histologic changes that occur, our understanding of this link continues to expand and evolve. In this paper, we review the research on the impact of diet on skin aging. A number of long-term observational population studies have documented that healthier diets are linked to fewer signs of skin aging. Animal and laboratory studies have elucidated the biochemical processes that play a large role in the development of these clinical findings. A number of studies have also reported on the role of specific dietary compounds in impacting these processes, whether by combating or potentiating these forces. This body of research serves as guidance in recommending nutritional strategies that can combat the skin aging forces of oxidation, inflammation, and glycation.
Our systematic review assessed the impact of botanical fermented food (BFF) consumption on glucose, lipid, anthropometric, inflammatory and gut microbiota parameters, in adults with metabolic syndrome (MetS), MetS components or type 2 diabetes mellitus (T2DM). Embase, MEDLINE, Cochrane CENTRAL and Google Scholar were searched with no language limits, from inception to August 31, 2022, for eligible randomised controlled trials (RCTs). Two independent reviewers screened 6873 abstracts and extracted relevant data. Risk of bias (ROB) was assessed using the Cochrane Collaboration’s ROB2 tool. The final review included 26 RCTs, with 31 reports published between 2001 and 2022. Significant (p<0.05) within-group and between-group changes in cardiometabolic outcome means were reported in 23 and 19 studies, respectively. Gut microbiota composition was assessed in four studies, with two finding significant between-group differences. No significant difference between groups of any measured outcomes was observed in five studies. There were 14 studies at low ROB; ten were of some concern; and two were at high ROB. In 73% of included studies, BFF consumption by participants with obesity, MetS or T2DM led to significant between-group improvements in discrete cardiometabolic outcomes, including fasting blood glucose, lipid profile, blood pressure, waist circumference, body fat percentage, and C-reactive protein. BFF consumption increased the abundance of beneficial gut bacteria, such as Bifidobacterium and LAB, whilst reducing potential pathogens like Bacteroides . To determine the clinical significance of BFFs as therapeutic dietary adjuncts, their safety, tolerability and affordability must be balanced with the limited power and magnitude of these preliminary findings.
Fermented foods such as yogurt, kefir and sauerkraut have been part of the human diet throughout history and have gained attention in recent years due to their immense health and nutritional benefits. As a result, fermented foods are considered biofuel for the human microbiome which helps to boost the immune system. Fermented foods are those foods and beverages that are produced by employing specific microbial‐based fermentation aids such as yeasts and bacteria, particularly lactic acid bacteria (LAB). Through controlled enzymatic reactions, these microbial cultures transform food components as substrates into value‐added products promoting various healthy fermentative activities. These microbes in fermented foods also produce compounds that can inhibit food spoilage and pathogenic microorganisms, thereby extending the product shelf of fermented products. Probiotics are live microbiota with beneficial health properties, prevent gastrointestinal diseases and modulate the human microbiome. Thus, foods that are fermented by certain strains of probiotic bacteria that exhibit evidence of health benefits are referred to as probiotic fermented foods. This review describes fermented and functional foods, probiotics and their relationship to human health. In addition, we offer our perspective on the distinct differences between probiotic and fermented foods to promote awareness for consumers and key stakeholders regarding these highly functional and nutritionally fermented food products.
This study aimed to investigate the effects of administration of xanthan gum-based fluid thickener on the regulation of postprandial blood glucose level, gene expression in the gastrointestinal tract, and gut microbiome. Six-week-old Sprague-Dawley rats were divided into two groups: with (Th group) and without (Co group) the administration of a xanthan gum-based fluid thickener for 5 wks. Blood glucose levels at 60 and 90 min after glucose administration were substantially decreased in the Th group. Glp1 and Glp1r expression in the ileum was significantly upregulated after continuous administration of thickener. RNA-seq analysis revealed that the cholesterol homeostasis, fatty acid metabolism, and glycolysis gene sets were enriched in the ileum of Th group. Microbial composition in the gut was altered after administrating the fluid thickener, and relative abundance in Erysipelotrichales and Christensenellaceae showed positive correlation with Glp1 and Glp1r expression in the ileum. Xanthan gum-based fluid thickener may ameliorate glucose/lipid metabolism.
In this study, we investigated the physicochemical characteristics and antioxidant activity of fermented vinegar using onion and black onion. When the onion and black onion were fermented in alcohol for 8 days, the alcohol content in both onion vinegar (OV) and black onion vinegar (BV) increased, whereas their sugar content decreased. The alcohol content was higher in OV than that in BV. When the onion and black onion were fermented in acetic acid for 20 days, the pH of both OV and BV decreased, whereas their total acidity increased. After fermentation, the main free sugars of OV and BV were fructose and glucose, and they were higher in BV than in OV. The major organic acids in OV and BV were acetic acid and malic acid, and the content of acetic acid was higher in BV than that in OV. In addition, OV and BV increased 1,1’-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS+) radical scavenging activities in a dose-dependent manner. Furthermore, DPPH and ABTS+ radical scavenging activities were greater in black onion juice than in onion juice. The BV showed a higher DPPH and ABTS+ radical scavenging activities than OV. Therefore, BV is the more suitable antioxidant functional vinegar through radical scavenging activity.
Vinegar ingestion at mealtime is gaining popularity for its antiglycemic effects; however, it is among the most acidic consumable substances. This study examined tooth wear in healthy adults participating in an 8-week randomized trial examining the effect of daily vinegar ingestion on insulin sensitivity and visceral fat reduction. Twice daily participants consumed a vinegar drink (two tablespoons vinegar in a cup of water; 3.6 g acetic acid) or a commercial vinegar pill (control, 0.045 g acetic acid) at mealtime. Participants were screened for dental erosion using the basic erosive wear examination (BEWE) by a blinded registered dental hygienist at trial baseline and week 8. Mean BEWE scores did not change in the control group but increased 18% in the vinegar group over the 8-week study (P = .038). Given the current popularity of vinegar as a medicinal agent, practitioners should caution patients who utilize this strategy on the possibility of erosive tooth wear. Trial registration: This trial was registered at ClinicalTrials.gov (NCT03577834) on July 5, 2018 and the institutional review board at Arizona State University provided ethical approval (STUDY00005418).
Hyperglycemia and hyperuricemia are both metabolic disorders related to excessive amount of metabolites in blood, which are considered as high risk factors for the development of many chronic diseases. Enzymes, cells, tissues and organs, which are relevant to metabolism and excretion of glucose and UA, are usually regarded to be the targets in treatment of hyperglycemia and hyperuricemia. Several drugs have been commonly applied to combat hyperglycemia and hyperuricemia through various targets but with unignorable side effects. Anthocyanins have become promising alternatives against hyperglycemia and hyperuricemia because of their bio-activities with little side effects. Structurally different anthocyanins from berry fruits, cherries and purple sweet potato lead to the diverse functional activity and property. This review is aimed to illustrate the specific targets that are available for anthocyanins from berry fruits, cherries and purple sweet potato in hyperglycemia and hyperuricemia management, as well as discuss the structure-activity relationship, and the underlying mechanisms associated with intracellular signaling pathway, anti-oxidative stress and anti-inflammation. In addition, the relationship of hyperglycemia and hyperuricemia, and the possibly regulative role of anthocyanins against them, along with the effects of anthocyanins in clinical trial are mentioned.
The aim of this work was to evaluate the inhibitory activities of organic acids identified from commercial vinegars on α-amylase and α-glucosidase. Six organic acids (acetic, citric, lactic, malic, succinic, and tartaric) were identified in nine commercial vinegars, whose contents varied considerably depending on the raw materials. Most of the fruit vinegars, comprised of various organic acids, were found to be more effective inhibitors against digestive enzymes than grain vinegars containing mainly acetic acid. Citric acid had the lowest IC50 values for α-amylase and α-glucosidase activities 0.64±0.04 μM/mL and 8.95±0.05 μM/mL, respectively, and thus exhibited the strongest antidiabetic effect. Mulberry fruit vinegar containing the highest content of total organic acid (111.02±1.50 mg/mL) showed the strongest digestive enzyme inhibitory impact. The results indicate that vinegars with higher contents of various organic acids hold strong potential against digestive enzymes.
Acetic fermentation is a method for processing plant material which has been known since antiquity. Balsamic and apple cider vinegars are investigated as antibacterial, anti-obesity, and anti-diabetic remedies. However, there is little information about vinegars fermented from aromatic herbs and edible plants. The aim of this study was to compare extracts used for culinary and medicinal purposes according to their composition, antioxidant power, and genoprotective properties. Fermented vinegars, acetic macerates, decoctions, and tinctures in 70% ethanol from raspberries, apple peels, rosehips, lavender, mint, and rose petals were prepared. Polyphenols, ascorbate, carotenoid concentrations, and antioxidant power were analyzed. The polyphenols were identified using HPLC (high-performance liquid chromatography). The genoprotective properties were measured using a comet assay on lymphocytes. Fermented vinegars were poorest in phytochemicals in comparison to tinctures, decoctions, or acetic macerates, although they contained the highest concentration of metal ions. The antioxidant abilities were correlated to the phenolic content of extract. None of the extracts induced DNA damages into lymphocytes. The rosehip and rose petal extracts revealed the highest genoprotective abilities, while mint and apple fermented vinegars and decoctions had the lowest. Fermented vinegars are not a rich source of phytochemicals and they show weak genoprotective abilities, but, in increasing demand for antioxidants, any form of phytochemical sources is an added-value in diet.
Introduction. Vinegar is known with
its positive impact on post-prandial
dysmetabolism. The aim of this study was to
elucidate the acute effects of high amount
vinegar on blood glucose and lipid
parameters.
Material and Methods. Sixteen type
2 diabetic patients who had been treated
with metformin only, were served a
standardized meal to which 50 g vinegar
was added on the first day but not on the
second day. Blood glucose, insulin and lipid
levels were measured during fasting and at
the second hour after intake of the meal.
Results. Postprandial increase in the
levels of venous blood glucose
measurements was not different in the
vinegar group when compared with the
reference group (p=0.163). There was no
significant difference on postprandial
insulinemia (p=0.796). While investigating
the effect of the vinegar on postprandial
lipemia, no differences in triglyceride
changes was found between vinegar and
reference group (p=0.816).
Conclusion. In this study in which we
have tried to find an answer to the question
about the effect of high amount grape
vinegar on postprandial metabolism, no
favorable or deleterious effect on
postprandial changes of glycemia and
lipemia was found.
Key words: postprandial
dysmetabolism, type 2 diabetes mellitus,
vinegar.
Uremic pruritus is a common complication in patients with chronic kidney disease. While its cause is not known for certain, different treatments are currently applied. This study aimed to compare the effects of Avena sativa, diluted vinegar, and hydroxyzine on the reduction of uremic pruritus.
In this crossover randomized clinical trial, 23 hemodialysis patients with uremic pruritus were randomly divided into 3 groups. The first group was treated with Avena sativa lotion, twice a day, for as long as 2 weeks; the second group received diluted vinegar; and the third group took hydroxyzine tablets for the same time span. After 3-day-long washout periods, the therapeutic methods were crossed over. The data were collected by a pruritus scale and a visual analogue scale, which were completed before and after the interventions.
Avena sativa lotion significantly decreased the mean scores of pruritus intensity, consequences, and the verbal descriptor, although it did not have a significant effect on the frequency of pruritus and the pruritic surface. Vinegar and hydroxyzine significantly decreased all of the scores. Conclusions. Avena sativa, vinegar, and hydroxyzine were effective in decreasing pruritus. Diluted vinegar and Avena sativa can be used as a complement to hydroxyzine, which is itself a common pharmaceutical therapy.
Background and aims:
Vinegar has been shown to have a glucose-lowering effect in patients with glucose abnormalities. However, the mechanisms of this effect are still obscure. The aim of this randomised, crossover study was to investigate the effect of vinegar on glucose metabolism in muscle which is the most important tissue for insulin-stimulated glucose disposal.
Materials and methods:
Eleven subjects with DM2 consumed vinegar or placebo (at random order on two separate days, a week apart), before a mixed meal. Plasma glucose, insulin, triglycerides, nonesterified fatty acids (NEFA), and glycerol were measured preprandially and at 30-60 min for 300 min postprandially from the radial artery and from a forearm vein. Muscle blood flow was measured with strain-gauge plethysmography. Glucose uptake was calculated as the arteriovenous difference of glucose multiplied by blood flow.
Results:
Vinegar compared to placebo (1) increased forearm glucose uptake (p = 0.0357), (2) decreased plasma glucose (p = 0.0279), insulin (p = 0.0457), and triglycerides (p = 0.0439), and (3) did not change NEFA and glycerol.
Conclusions:
In DM2 vinegar reduces postprandial hyperglycaemia, hyperinsulinaemia, and hypertriglyceridaemia without affecting lipolysis. Vinegar's effect on carbohydrate metabolism may be partly accounted for by an increase in glucose uptake, demonstrating an improvement in insulin action in skeletal muscle. This trial is registered with Clinicaltrials.gov NCT02309424.
The impact of honey or vinegar on several metabolic abnormalities has been studied separately, a mixture of these two ingredients known as honey vinegar syrup (HVS) has not been investigated previously so far. The aim of this study was to assess the impact of HVS consumption (Iranian's traditional syrup) on glycemic parameters and lipid profiles in healthy individuals.
We conducted a 4-week, randomized, controlled, parallel study consisting of two groups of nonobese healthy volunteers. All subjects were asked to stay on their normal diet. Intervention group (n = 36) received a cup of HVS daily in the evening snack for 4-week (250 cc syrup contains 21.66 g honey vinegar). Assessments of fasting blood sugar (FBS), insulin, homeostasis model assessment of insulin resistance (HOMA-IR), total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) were conducted at the baseline and after 4-week of study.
We observed no significant effect of HVS on FBS, HOMA-IR, LDL-C and TG. A significant effect of HVS was found on increasing fasting insulin and HOMA-IR and reduction in TC level only in intervention group (Δ =3.39 P = 0.01, Δ =1.65 P = 0.03, Δ = -9.43 P = 0.005, respectively). Changes of FBS, TG and LDL-C were 1.83 mg/dl, -1.53 mg/dl and - 3.99 mg/dl respectively in the intervention group. These changes were not significant. An unfavorable and significant reduction in HDL-C level was also observed between two groups (Δ = -4.82 P < 0.001 in the intervention group).
Honey vinegar syrup increased fasting insulin level and decreased TC level in the intervention group. HVS had an unfavorable effect on HDL-C level. Further prospective investigations are warranted to confirm these findings.
Background/objectives:
Previous studies support the glucose-lowering effect of vinegar. However, the effect of vinegar on muscle glucose metabolism and endothelial function has not been studied in humans. This open, randomized, crossover, placebo-controlled study aims to investigate the effects of vinegar on muscle glucose metabolism, endothelial function and circulating lipid levels in subjects with impaired glucose tolerance (IGT) using the arteriovenous difference technique.
Subjects/methods:
Eight subjects with IGT (4 males, age 46±10 years, body mass index 30±5) were randomised to consume 0.50 mmol vinegar (6% acetic acid) or placebo before a mixed meal. Plasma samples were taken for 300 min from the radial artery and the forearm vein for measurements of glucose, insulin, triglycerides, non-esterified fatty acids (NEFAs) and glycerol. Muscle blood flow was measured with strain gauge plethysmography. Glucose flux was calculated as the arteriovenous difference of glucose multiplied by the blood flow rates.
Results:
Vinegar compared with placebo: (1) decreased arterial plasma insulin (Poverall<0.001; P75 min=0.014, β=-42), (2) increased forearm blood flow (Poverall<0.001; P240 min=0.011, β=1.53; P300 min=0.023, β=1.37), (3) increased muscle glucose uptake (Poverall<0.001; P60 min=0.029, β=2.78) and (4) decreased arterial plasma triglycerides (Poverall=0.005; P240 min<0.001, β=-344; P300 min<0.001, β=-373), without changing NEFA and glycerol.
Conclusions:
In individuals with IGT, vinegar ingestion before a mixed meal results in an enhancement of muscle blood flow, an improvement of glucose uptake by the forearm muscle and a reduction of postprandial hyperinsulinaemia and hypertriglyceridaemia. From this point of view, vinegar may be considered beneficial for improving insulin resistance and metabolic abnormalities in the atherogenic prediabetic state.
Apple cider vinegar has been traditionally used since many years ago to treat a certain number of diseases including hyperlipidemia which is known as a risk factor for atherosclerosis. Early prevention and treatment of atherosclerosis can prevent complications of cardiovascular diseases. Hence, the present study aimed to review the influence of apple cider vinegar consumption on reducing blood lipid levels. This quasi-experiment study(time series design) was carried out on 19 patients with hyperlipidemia. The subjects had been referred to a cardiologist and agreed to consume apple cider vinegar. At baseline, blood samples were obtained to measure cholesterol, triglyceride, low density lipoprotein (LDL), and high density lipoprotein (HDL). The tests were repeated at two, four, and eight weeks of vinegar consumption. The results were analyzed using repeated measurement analysis. There were significant reduction in the serum levels of total cholesterol (p < 0.001), triglyceride (p = 0.020), and LDL (p = 0.001) after eight weeks of consuming apple cider vinegar and with an increased HDL levels but the trend was not statistically significant (p = 0.200). Consumption of apple cider vinegar over a 8 week period had a beneficial effect in significant reductions in harmful blood lipids and is recommended as a simple and cost-effective treatment for hyperlipidemia. Introduction Plasma lipoprotein abnormalities and lipid metabolism disorder are known and proved risk factors for atherosclerosis. 1 Besides their impact on mortality, they have substantial, and in some cases modifiable, influences on disability rates.
Background
Vinegar is promoted as a natural appetite suppressant, based on previous reports that vinegar ingestion significantly increases subsequent satiety. However there are concerns about the appropriateness and safety of this advice and it is unclear if poor product palatability may explain previously published effects on appetite.Objective
To investigate if vinegar palatability and tolerability have a role in suppressing appetite and food intake in two sequential and related acute human feeding studies.Subjects and methodsHealthy, young, normal weight unrestrained eaters were recruited to Study 1 (n=16), an acute feeding study supplying vinegar within both palatable and unpalatable drinks alongside a mixed breakfast in comparison to a non-vinegar control; and to Study 2 (n=14), a modified sham feeding study (taste only without ingestion) comparing vinegar to a non-vinegar control following a milkshake preload. Both studies were a randomised cross-over balanced design for the assessment of appetite, energy intake and glycemic response.ResultsIn Study 1 ingestion of vinegar significantly reduced quantitative and subjective measures of appetite, which were accompanied by significantly higher nausea ratings, with Unpal treatment having the greatest effect. Significant correlations between palatability ratings and appetite measures were found. In Study 2, orosensory stimulation with vinegar did not influence subsequent subjective or quantitative measures of appetite compared to control.Conclusions
These studies indicate that vinegar ingestion enhances satiety while orosensory stimulation alone does not, and that these effects are largely due to poor tolerability following ingestion invoking feelings of nausea. On this basis the promotion of vinegar as a natural appetite suppressant does not seem appropriate.International Journal of Obesity accepted article preview online, 27 August 2013. doi:10.1038/ijo.2013.157.
Objective: Funnel plots (plots of effect estimates against sample size) may be useful to detect bias in meta-analyses that were later contradicted by large trials. We examined whether a simple test of asymmetry of funnel plots predicts discordance of results when meta-analyses are compared to large trials, and we assessed the prevalence of bias in published meta-analyses. Design: Medline search to identify pairs consisting of a meta-analysis and a single large trial (concordance of results was assumed if effects were in the same direction and the meta-analytic estimate was within 30
The purpose of this study was to evaluate the effect of rice vinegar administered via nasogastric feeding tube on catheter-associated bacteriuria in patients with long-term urinary catheterization.
The authors conducted a randomized controlled trial (n = 60) to compare treatment with dilute vinegar and usual care. The authors recruited patients with chronic catheters from a long-term care facility in northern Taiwan. The experimental group received 100 ml of diluted rice vinegar each day for 4 weeks, whereas the control group received 100 ml of water. The authors analyzed urine weekly and cultured it on Day 28.
The generalized estimating equation results showed significant between-group differences in urinary pH, bacterial titer, and turbidity. No patient in the experimental group, but three in the control group, exhibited symptomatic urinary tract infection (UTI). Rice vinegar may decrease bacteriuria. Medicinal use of vinegar may decrease the risk of symptomatic UTI, but further study is needed to determine the effects of ingesting vinegar for a longer period and with a larger sample size.
The aim of this article is to evaluate the pros and cons of a specific impact of postprandial hyperglycemia and glycemic variability on the--mainly cardiovascular (CV)--complications of diabetes, above and beyond the average blood glucose (BG) as measured by HbA(1c) or fasting plasma glucose (FPG). The strongest arguments in favor of this hypothesis come from impressive pathophysiological studies, also in the human situation. Measures of oxidative stress and endothelial dysfunction seem to be especially closely related to glucose peaks and even more so to fluctuating high and low glucose concentrations and can be restored to normal by preventing those glucose peaks or wide glucose excursions. The epidemiological evidence, which is more or less confined to postprandial hyperglycemia and postglucose load glycemia, is also rather compelling in favor of the hypothesis, although certainly not fully conclusive as there are also a number of conflicting results. The strongest cons are seen in the missing evidence as derived from randomized prospective intervention studies targeting postprandial hyperglycemia longer term, i.e., over several years, and seeking to reduce hard CV end points. In fact, several such intervention studies in men have recently failed to produce the intended beneficial outcome results. As this evidence by intervention is, however, key for the ultimate approval of a treatment concept in patients with diabetes, the current net balance of attained evidence is not in favor of the hypothesis here under debate, i.e., that we should care about postprandial hyperglycemia and glycemic variability. The absence of a uniformly accepted standard of how to estimate these parameters adds a further challenge to this whole debate.
The objective of this research is to gain a greater understanding of the cause of fasting and postprandial hyperglycemia in people with type 2 diabetes. Endogenous glucose production is excessive before eating and fails to appropriately suppress after eating in people with type 2 diabetes. This is due in part to impaired insulin-induced suppression of endogenous glucose production, which is observed early in the evolution of type 2 diabetes. Increased rates of gluconeogenesis and perhaps glycogenolysis contribute to hepatic insulin resistance. Insulin-induced stimulation of hepatic glucose uptake and hepatic glycogen synthesis are reduced in people with type 2 diabetes primarily due to decreased uptake of extracellular glucose presumably because of inadequate activation of hepatic glucokinase. Delayed insulin secretion results in higher peak glucose concentrations particularly when suppression of glucagon is impaired, whereas insulin resistance prolongs the duration of hyperglycemia, which can be marked when both hepatic and extra-hepatic insulin resistance are present.
The premise of these studies, as well as those performed by many other investigators, is that an understanding of the pathogenesis of type 2 diabetes will enable the development of targeted therapies that are directed toward correcting specific metabolic defects in a given individual. I, as well as many other investigators, believe that such therapies are likely to be more effective and to have a lower risk than would occur if everyone were treated the same regardless of the underlying cause of their hyperglycemia. While we do not yet have sufficient knowledge to truly individualize therapy, in my opinion this approach will be the norm in the not too distant future.
Earlier studies have shown that the addition of vinegar in a carbohydrate-rich meal lowers glucose and insulin response in healthy individuals. The mechanism of how this is accomplished, however, remains unclear. The aim of this study is to examine the effect of vinegar on glucose and insulin response in patients with type II diabetes (T2D) in relation to the type of carbohydrates consumed in a meal.
Sixteen patients with T2D were divided into two groups, matched for age, gender and HbA(1c). Patients in the first group (group A) were given a high-glycaemic index (GI) meal (mashed potatoes and low-fat milk) on two different days, with and without the addition of vinegar, respectively. In the second group (group B), patients were given an isocaloric meal with the same nutrient composition, but low GI (whole grain bread, lettuce and low-fat cheese). Postprandial plasma glucose and insulin values were measured every 30 min for 2 h.
In group A, the incremental area under the curve of glucose (GiAUC(120)) was lower after the addition of vinegar (181+/-78 mmol min/l vs 311+/-124 mmol min/l, P=0.04). The iAUC of insulin (IiAUC(120)) was also reduced, but the difference was of marginal statistical significance (2368+/-1061 microU min/ml vs 3545+/-2586 microU min/ml, P=0.056). In group B, the addition of vinegar did not affect either the GiAUC(120) (229+/-38 mmol min/l vs 238+/-25 mmol min/l, P=0.56) or the IiAUC(120) (2996+/-1302 microU min/ml vs 3007+/-1255 microU min/ml, P=0.98).
We conclude that the addition of vinegar reduces postprandial glycaemia in patients with T2D only when it is added to a high-GI meal.
Although previous studies show that vinegar improves insulin sensitivity in healthy or insulin-resistant subjects (1,2), information on the effect of vinegar in type 1 diabetes is absent. Given the beneficial effects of maintaining tight glycemic control on the development of complications, there is much interest in identifying diet patterns that could possibly reduce hyperglycemia. The aim of this study was to investigate the effect of vinegar in type 1 diabetes.
Ten men with type 1 diabetes (aged 32 ± 3 years, BMI 24 ± 1 kg/m2, diabetes duration 14 ± 3 years, A1C 6.7 ± 0.2%) treated with rapid-acting insulin preprandially and long-acting insulin once daily were studied after an overnight fast.
The study was approved by …
The antiglycemic effects of vinegar have been known for more than a century and have been demonstrated in animal as well as human studies. Although the exact mechanism of vinegar action is not known, several possibilities have been proposed including suppression of disaccharidase activity, delayed gastric emptying, enhanced glucose uptake in the periphery and conversion to glycogen, and increased satiety. We hypothesized that by suppressing endogenous insulin secretion, we could estimate the glucose absorption rate from an oral carbohydrate load and determine the effects of vinegar ingestion on this rate. To do so, 5 subjects had 4 studies at 1-week intervals, randomly receiving placebo twice (60 mL water) and vinegar twice (20 mL apple cider vinegar, 40 mL water), followed 2 minutes later by a meal of mashed potatoes (0.75 g carbohydrate per kilogram body weight) that was consumed over 20 minutes. At the beginning of the meal, an oral octreotide/insulin suppression test (25-microg bolus octreotide; 180 minute infusion 5 mU/m(2) body surface area per minute regular human insulin, and 0.5 microg/min octreotide) was begun. Blood samples for insulin and glucose were drawn at 20-minute intervals. The oral octreotide/insulin suppression test suppressed endogenous insulin secretion for the first 100 minutes of the study. During this time, the rate of rise of glucose was modestly but significantly (P = .01) greater after vinegar ingestion compared to placebo, suggesting that vinegar does not act to decrease glycemia by interference with enteral carbohydrate absorption.
The glycaemic index (GI) concept was originally introduced to classify different sources of carbohydrate (CHO)-rich foods, usually having an energy content of >80 % from CHO, to their effect on post-meal glycaemia. It was assumed to apply to foods that primarily deliver available CHO, causing hyperglycaemia. Low-GI foods were classified as being digested and absorbed slowly and high-GI foods as being rapidly digested and absorbed, resulting in different glycaemic responses. Low-GI foods were found to induce benefits on certain risk factors for CVD and diabetes. Accordingly it has been proposed that GI classification of foods and drinks could be useful to help consumers make 'healthy food choices' within specific food groups. Classification of foods according to their impact on blood glucose responses requires a standardised way of measuring such responses. The present review discusses the most relevant methodological considerations and highlights specific recommendations regarding number of subjects, sex, subject status, inclusion and exclusion criteria, pre-test conditions, CHO test dose, blood sampling procedures, sampling times, test randomisation and calculation of glycaemic response area under the curve. All together, these technical recommendations will help to implement or reinforce measurement of GI in laboratories and help to ensure quality of results. Since there is current international interest in alternative ways of expressing glycaemic responses to foods, some of these methods are discussed.
In medical research data are often collected serially on subjects. The statistical analysis of such data is often inadequate in two ways: it may fail to settle clinically relevant questions and it may be statistically invalid. A commonly used method which compares groups at a series of time points, possibly with t tests, is flawed on both counts. There may, however, be a remedy, which takes the form of a two stage method that uses summary measures. In the first stage a suitable summary of the response in an individual, such as a rate of change or an area under a curve, is identified and calculated for each subject. In the second stage these summary measures are analysed by simple statistical techniques as though they were raw data. The method is statistically valid and likely to be more relevant to the study questions. If this method is borne in mind when the experiment is being planned it should promote studies with enough subjects and sufficient observations at critical times to enable useful conclusions to be drawn. Use of summary measures to analyse serial measurements, though not new, is potentially a useful and simple tool in medical research.
It has been suggested that the quality of clinical trials should be assessed by blinded raters to limit the risk of introducing bias into meta-analyses and systematic reviews, and into the peer-review process. There is very little evidence in the literature to substantiate this. This study describes the development of an instrument to assess the quality of reports of randomized clinical trials (RCTs) in pain research and its use to determine the effect of rater blinding on the assessments of quality. A multidisciplinary panel of six judges produced an initial version of the instrument. Fourteen raters from three different backgrounds assessed the quality of 36 research reports in pain research, selected from three different samples. Seven were allocated randomly to perform the assessments under blind conditions. The final version of the instrument included three items. These items were scored consistently by all the raters regardless of background and could discriminate between reports from the different samples. Blind assessments produced significantly lower and more consistent scores than open assessments. The implications of this finding for systematic reviews, meta-analytic research and the peer-review process are discussed.
Funnel plots (plots of effect estimates against sample size) may be useful to detect bias in meta-analyses that were later contradicted by large trials. We examined whether a simple test of asymmetry of funnel plots predicts discordance of results when meta-analyses are compared to large trials, and we assessed the prevalence of bias in published meta-analyses.
Medline search to identify pairs consisting of a meta-analysis and a single large trial (concordance of results was assumed if effects were in the same direction and the meta-analytic estimate was within 30% of the trial); analysis of funnel plots from 37 meta-analyses identified from a hand search of four leading general medicine journals 1993-6 and 38 meta-analyses from the second 1996 issue of the Cochrane Database of Systematic Reviews.
Degree of funnel plot asymmetry as measured by the intercept from regression of standard normal deviates against precision.
In the eight pairs of meta-analysis and large trial that were identified (five from cardiovascular medicine, one from diabetic medicine, one from geriatric medicine, one from perinatal medicine) there were four concordant and four discordant pairs. In all cases discordance was due to meta-analyses showing larger effects. Funnel plot asymmetry was present in three out of four discordant pairs but in none of concordant pairs. In 14 (38%) journal meta-analyses and 5 (13%) Cochrane reviews, funnel plot asymmetry indicated that there was bias.
A simple analysis of funnel plots provides a useful test for the likely presence of bias in meta-analyses, but as the capacity to detect bias will be limited when meta-analyses are based on a limited number of small trials the results from such analyses should be treated with considerable caution.
To understand how blood glucose level is lowered by oral administration of vinegar, we examined effects of acetic acid on glucose transport and disaccharidase activity in Caco-2 cells. Cells were cultured for 15 d in a medium containing 5 mmol/L of acetic acid. This chronic treatment did not affect cell growth or viability, and furthermore, apoptotic cell death was not observed. Glucose transport, evaluated with a nonmetabolizable substrate, 3-O-methyl glucose, also was not affected. However, the increase of sucrase activity observed in control cells (no acetic acid) was significantly suppressed by acetic acid (P < 0.01). Acetic acid suppressed sucrase activity in concentration- and time-dependent manners. Similar treatments (5 mmol/L and 15 d) with other organic acids such as citric, succinic, L-maric, L-lactic, L-tartaric and itaconic acids, did not suppress the increase in sucrase activity. Acetic acid treatment (5 mmol/L and 15 d) significantly decreased the activities of disaccharidases (sucrase, maltase, trehalase and lactase) and angiotensin-I-converting enzyme, whereas the activities of other hydrolases (alkaline phosphatase, aminopeptidase-N, dipeptidylpeptidase-IV and gamma-glutamyltranspeptidase) were not affected. To understand mechanisms underlying the suppression of disaccharidase activity by acetic acid, Northern and Western analyses of the sucrase-isomaltase complex were performed. Acetic acid did not affect the de novo synthesis of this complex at either the transcriptional or translational levels. The antihyperglycemic effect of acetic acid may be partially due to the suppression of disaccharidase activity. This suppression seems to occur during the post-translational processing.
Foods with a low glycemic index are increasingly being acknowledged as beneficial in relation to the insulin resistance syndrome. Certain organic acids can lower the glycemic index of bread products. However, the possible effect of acids in fermented milk products on the glycemic index and on insulinemic characteristics has not been addressed. The metabolic effects of fermented milk or pickled products used as additives to mixed meals have also not been addressed.
One objective was to characterize the glycemic and insulinemic responses after intake of regular or fermented milk products (study 1). In addition, the acute metabolic effect of fermented milk (yogurt) and pickled cucumber as supplements to a traditional breakfast based on a high-glycemic index bread was evaluated (study 2).
Ten healthy volunteers were served different breakfast meals after an overnight fast. Capillary blood samples were collected before and during 2 (study 1) or 3 (study 2) h after the meal. White-wheat bread was used as a reference meal in both studies.
The lactic acid in the fermented milk products did not lower the glycemic and insulinemic indexes. Despite low glycemic indexes of 15-30, all of the milk products produced high insulinemic indexes of 90-98, which were not significantly different from the insulinemic index of the reference bread. Addition of fermented milk (yogurt) and pickled cucumber to a breakfast with a high-glycemic index bread significantly lowered postprandial glycemia and insulinemia compared with the reference meal. In contrast, addition of regular milk and fresh cucumber had no favorable effect on the metabolic responses.
Milk products appear insulinotropic as judged from 3-fold to 6-fold higher insulinemic indexes than expected from the corresponding glycemic indexes. The presence of organic acids may counteract the insulinotropic effect of milk in mixed meals.
To investigate the potential of acetic acid supplementation as a means of lowering the glycaemic index (GI) of a bread meal, and to evaluate the possible dose-response effect on postprandial glycaemia, insulinaemia and satiety.
In all, 12 healthy volunteers participated and the tests were performed at Applied Nutrition and Food Chemistry, Lund University, Sweden.
Three levels of vinegar (18, 23 and 28 mmol acetic acid) were served with a portion of white wheat bread containing 50 g available carbohydrates as breakfast in randomized order after an overnight fast. Bread served without vinegar was used as a reference meal. Blood samples were taken during 120 min for analysis of glucose and insulin. Satiety was measured with a subjective rating scale.
A significant dose-response relation was seen at 30 min for blood glucose and serum insulin responses; the higher the acetic acid level, the lower the metabolic responses. Furthermore, the rating of satiety was directly related to the acetic acid level. Compared with the reference meal, the highest level of vinegar significantly lowered the blood glucose response at 30 and 45 min, the insulin response at 15 and 30 min as well as increased the satiety score at 30, 90 and 120 min postprandially. The low and intermediate levels of vinegar also lowered the 30 min glucose and the 15 min insulin responses significantly compared with the reference meal. When GI and II (insulinaemic indices) were calculated using the 90 min incremental area, a significant lowering was found for the highest amount of acetic acid, although the corresponding values calculated at 120 min did not differ from the reference meal.
Supplementation of a meal based on white wheat bread with vinegar reduced postprandial responses of blood glucose and insulin, and increased the subjective rating of satiety. There was an inverse dose-response relation between the level of acetic acid and glucose and insulin responses and a linear dose-response relation between acetic acid and satiety rating. The results indicate an interesting potential of fermented and pickled products containing acetic acid.
Previous studies on healthy people show that vinegar delays gastric emptying and lowers postprandial blood glucose and insulin levels. The aim of this study was to investigate the effect of apple cider vinegar on delayed gastric emptying rate on diabetes mellitus patients.
Ten patients with type 1 diabetes and diabetic gastroparesis, including one patient who had undergone vagotomy, were included and completed the investigator blinded crossover trial. The gastric emptying rate (GER) was measured using standardized real-time ultrasonography. The GER was calculated as the percentage change in the antral cross-sectional area 15 and 90 minutes after ingestion of 300 g rice pudding and 200 ml water (GER1), or 300 g rice pudding and 200 ml water with 30 ml apple cider vinegar (GER2). The subjects drank 200 ml water daily before breakfast one week before the measurement of GER1. The same subjects drank 200 ml water with 30 ml vinegar daily before breakfast for two weeks before the measurement of GER2.
The median values of GER1 and GER2 were 27% and 17%, respectively. The effect of vinegar on the rate of gastric emptying was statistically significant (p < 0.05).
This study shows that vinegar affects insulin-dependent diabetes mellitus patients with diabetic gastroparesis by reducing the gastric emptying rate even further, and this might be a disadvantage regarding to their glycaemic control.
ISRCTN33841495.
The final common pathway for most systematic reviews is a statistical summary of the data, or meta-analysis . The com plex methods used in meta-analyses should always be complemented by clinical acumen and common sense in designing the protocol of a systematic review, deciding which data can be combined, and determining whether data should be combined. Both continuous and binary data can be pooled. Most meta-analyses summarize data from randomized trials, but other applications, such as the evaluation of diagnostic test performance and observa tional studies, have also been developed. The statistical methods of meta-analysis aim at evaluating the diversity (heterogeneity) among the results of different studies, exploring and explaining observed heterogeneity, and es timating a common pooled effect with increased precision. Fixed-effects models assume that an intervention has a single true effect, whereas random-effects models assume that an effect may vary across studies. Meta-regression analyses, by using each study rather than each patient as a unit of observation, can help to evaluate the effect of individual variables on the magnitude of an observed effect and thus may sometimes explain why study results differ. It is also important to assess the robustness of con clusions through sensitivity analyses and a formal evalua tion of potential sources of bias, including publication bias and the effect of the quality of the studies on the observed effect.