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Vinegar Consumption Increases Insulin-Stimulated Glucose Uptake by the Forearm Muscle in Humans with Type 2 Diabetes

  • Hellenic National Diabetes Centre

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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 NCT02309424.
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Clinical Study
Vinegar Consumption Increases Insulin-Stimulated Glucose
Uptake by the Forearm Muscle in Humans with Type 2 Diabetes
Panayota Mitrou,1Eleni Petsiou,2Emilia Papakonstantinou,2
Eirini Maratou,1Vaia Lambadiari,2Panayiotis Dimitriadis,3Filio Spanoudi,2
Sotirios A. Raptis,1,2 and George Dimitriadis2
1Hellenic National Center for Research, Prevention and Treatment of Diabetes Mellitus and Its Complications (HNDC),
3 Ploutarchou Street, 10675 Athens, Greece
22nd Department of Internal Medicine and Research Institute, Athens University Medical School, Attikon University Hospital,
1 Rimini Street, 12462 Haidari, Greece
3Department of Water Resources and Environmental Engineering, School of Civil Engineering, NTUA, Heroon Polytechniou 5-9,
15780 Athens, Greece
Correspondence should be addressed to Panayota Mitrou;
Received  December ; Accepted  April 
Academic Editor: Brunella Capaldo
Copyright ©  Panayota Mitrou et al. is is an open access article distributed under the Creative Commons Attribution
License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly
Background and Aims. Vinegar has been shown to have a glucose-lowering eect in patients with glucose abnormalities. However,
the mechanisms of this eect are still obscure. e aim of this randomised, crossover study was to investigate the eect of vinegar on
glucose metabolism in muscle which is the most important tissue for insulin-stimulated glucose disposal. Materials and Methods.
Eleven subjects with DM consumed vinegar or placebo (at random order on two separate days, a week apart), before a mixed
meal. Plasma glucose, insulin, triglycerides, nonesteried fatty acids (NEFA), and glycerol were measured preprandially and at –
 min for  min postprandially from the radial artery and from a forearm vein. Muscle blood ow was measured with strain-
gauge plethysmography. Glucose uptake was calculated as the arteriovenous dierence of glucose multiplied by blood ow. Results.
Vinegar compared to placebo () increased forearm glucose uptake (𝑝 = 0.0357), () decreased plasma glucose (𝑝 = 0.0279),
insulin (𝑝 = 0.0457), and triglycerides (𝑝 = 0.0439), and () did not change NEFA and glycerol. Conclusions.InDMvinegar
reduces postprandial hyperglycaemia, hyperinsulinaemia, and hypertriglyceridaemia without aecting lipolysis. Vinegars eect
on carbohydrate metabolism may be partly accounted for by an increase in glucose uptake, demonstrating an improvement in
insulin action in skeletal muscle. is trial is registered with NCT.
1. Introduction
A mixture of vinegar and olive oil is a common salad dressing
used in the Mediterranean diet. e main constituent of
vinegar is acetic acid, which gives vinegar its characteristic
taste and smell. e consumption of vinegar with meals was
used as a folk medicine for the treatment of diabetes before
any pharmacologic glucose-lowering therapy [,]. Recent
studies indicate that vinegar improves insulin sensitivity
in healthy volunteers, as well as in subjects with diabetes
e mechanisms by which vinegar reduces glucose levels
are still unclear. Acetic acid has been shown to delay gastric
emptying in healthy subjects []andpatientswithtype
diabetes []; alternatively, acetic acid may inhibit disaccha-
ridase activity in the small intestine and suppress the enteral
carbohydrate absorption []. In addition, vinegar ingestion
at bedtime has been shown to decrease fasting glucose levels
in humans with type  diabetes, suggesting an eect of acetic
acid on endogenous glucose production []. e mecha-
nisms of vinegar’s eect on peripheral tissues have been
studied in animals; these studies demonstrate that acetic acid
Hindawi Publishing Corporation
Journal of Diabetes Research
Volume 2015, Article ID 175204, 7 pages
Journal of Diabetes Research
feeding reduces glycolysis and promotes glycogen synthesis,
probably by reducing xylulose -phosphate accumulation in
the liver and phosphofructokinase- activity in muscle [
]. However, the eect of vinegar on glucose metabolism in
In addition, previous studies indicate that acetate may
also decrease circulating lipid levels []andprotectfrom
lipidaccumulationinliverandskeletalmuscle[]; however,
these data are derived either from animal models or from a
few human studies with serious limitations.
and () circulating plasma glucose, insulin, and lipid levels,
in patients with type  diabetes, using the arteriovenous
dierence technique across the forearm muscles.
2. Subjects and Methods
2.1. Subjects. A total of eleven nonsmoking volunteers with
type  diabetes ( males, age 53 ± 4 years, BMI 25 ± 1,and
HbAc 6.8 ± 0.3%) participated in the study. e subjects
were newly diagnosed (according to the current criteria
for the diagnosis of type  diabetes) without drug therapy
and free of diabetic complications or any other systematic
disease. eir diet and body weight were stable during the
last two months. All subjects were recreationally active,
without any specic training programme. e subjects were
instructed not to consume any acetic acid containing product
for two weeks prior to the study. e study was approved
by the hospital ethics committee, and subjects gave written
informed consent.
2.2. Experimental Protocol. All subjects arrived at the hospital
at  h aer an overnight fast and had the radial artery
(A) and a contralateral antecubital vein (V) draining the
forearm muscles catheterized [,]. Half an hour aer
catheterisation, the subjects were assigned to consume vine-
gar ( mL vinegar containing % acetic acid and  mL
water) or placebo ( mL water). e drinks were served at
random order on two separate days which were a week apart.
In each test,  min aer the drink, the subjects consumed
a meal composed of bread, cheese, turkey ham, orange
juice, butter, and a cereal bar ( kcal;  g carbohydrates,
within  min. Blood samples were withdrawn from both
sides preprandially and at – min intervals for  min
aer meal for measurements of glucose (Yellow Springs
Instruments, Yellow Springs, OH) and insulin (RIA; Linco
Research, St. Charles, MO) and from the radial artery for
measurements of triglycerides and NEFA and glycerol (Roche
Diagnostics, Mannheim, Germany). A full blood count was
performed preprandially.
Blood ow (BF) was measured immediately before each
blood sample in the forearm with mercury strain-gauge
plethysmography (Hokanson, Bellevue, WA) in the same arm
as the forearm vein.
2.3. Calculations. Glucose plasma levels were converted to
whole blood by using fractional hematocrit [,]. Areas
0300). Glucose uptake
by muscle was calculated as the arteriovenous dierence of
glucose multiplied by the blood ow rates [,].
Results are presented as mean ±sem. Normality tests were
applied to each dependent variable; all variables studied were
normally distributed. Dierences between the AUCs of the
dependent variables were tested with paired Student’s 𝑡-test
(SPSS Inc., Chicago, IL, USA).
3. Results
Vinegar ingestion was well tolerated; no side-eects were
3.1. Glucose Metabolism
3.1.1. Arterial Levels of Glucose and Insulin. Fasting blood
patients who had consumed placebo, blood glucose levels
raised postprandially reaching a peak aer  min, whereas
aer the consumption of vinegar postprandial glucose spikes
were decreased (Figure (a)). As a result, vinegar compared
to placebo reduced total blood glucose levels (AUC0300 min
 ± versus 3005 ± 149mM min, in vinegar and
placebo group, resp., 𝑝 = 0.0279).
Plasma insulin levels were similar between the two exper-
iments in the fasting state. However, vinegar consumption
decreased postprandial hyperinsulinaemia (AUC0300 min
 ± versus  ± mU/L min, in vinegar and
placebo group, resp., 𝑝 = 0.0457)(Figure (b)).
3.1.2. Forearm Blood Flow. Forearm blood ow rates were
similar in the fasting state and remained not statisti-
cally dierent throughout the whole postprandial period
in both groups (AUC0300 min  ± versus 1100 ±
86mL/min/ mL tissue mininvinegarandplacebo
group, resp.) (Figure (a)).
3.2. Muscle Glucose Metabolism. In the fasting state, glucose
uptake by the forearm muscles was similar in both groups.
Postprandially, muscle glucose uptake was increased in the
vinegar group compared to placebo (AUC0300 min 765 ± 87
versus  ± 𝜇mol/ mL tissue, in vinegar and placebo
group, resp., 𝑝 = 0.0357)(Figure (b)).
3.3. Lipid Metabolism. Fasting plasma triglyceride levels were
similar between the two groups. In the vinegar group post-
prandial hypertriglyceridemia was less evident, resulting in
decreased total plasma triglyceride levels (AUC0300 min 371±
34 versus 409 ± 38nmol/L min, in vinegar and placebo
group, resp., 𝑝 = 0.0439)(Figure (a)).
Fasting plasma NEFA and glycerol levels were not
dierent between the two groups. Postprandial plasma
NEFA (AUC0300 min 46 ± 5 versus 49 ± 10nmol/L min,
in vinegar and placebo group, resp.) and glycerol levels
Journal of Diabetes Research
60 0 60 120 180 240 300
Time (min)
Arterial plasma glucose (mmol/L)
0 60 120 180 240 300
Time (min)
Arterial plasma insulin (𝜇U/mL)
F : Arterial plasma glucose (𝑝 = 0.0279) (a) and insulin (𝑝 = 0.0457) (b) levels in subjects consuming vinegar (V+) or placebo (V).
At 𝑡=0min, a mixed meal was given.
0 60 120 180 240 300
Time (min)
Muscle blood ow
(mL/min/100 mL tissue)
0 60 120 180 240 300
Time (min)
Forearm glucose uptake
(𝜇mol/min/mL tissue)
F : Forearm muscle glucose uptake (𝑝 = 0.0357) (a) and muscle blood ow (p = NS) (b) in subjects consuming vinegar (V+) or placebo
(V). At 𝑡=0min, a mixed meal was given.
(AUC0300 min 4± 0.4 versus 5±0.5nmol/L min, in vinegar
and placebo group, resp.) were suppressed to the same extent
between groups (Figures (b) and (c)).
4. Discussion
e present study investigates the eects of vinegar on
circulating plasma glucose, insulin, and lipid levels, as well as
blood ow rates and glucose uptake by the forearm muscles,
in patients with type  diabetes. For this purpose we have used
the arteriovenous dierence technique across the forearm
muscle, aer the ingestion of a mixed meal, in order to create
a metabolic environment which permits the interaction of
insulin and substrates to be investigated under physiological
conditions [,,,].Toourknowledge,thisistherst
report examining the eect of vinegar on glucose metabolism
In the present study, vinegar reduced postprandial hyper-
that vinegar supplementation reduces postprandial blood
glucoselevelsinhealthysubjects[], as well as in subjects
with insulin resistance and type  diabetes [,]. It is
also in accordance with a preliminary study reporting that
regular vinegar ingestion reduces haemoglobin Ac values
in patients with type  diabetes []. However, our results
are not in agreement with a previous report showing that
vinegar ingestion before an oral glucose load did not improve
oral glucose tolerance in patients with type  diabetes [].
ese discrepancies could be explained, at least in part,
by dierences in the form of acetic acid, as well as the
kind of the test meal following acetic acid ingestion. As
shown previously, acetic acid reduced postprandial glucose
values when it was administered in the form of vinegar, but
not in the form of sodium acetate []. In addition, the
glucose-lowering eect of vinegar was evident when vinegar
Journal of Diabetes Research
0 60 120 180 240 300
Time (min)
Plasma triglycerides (𝜇mol/L)
0 60 120 180 240 300
Time (min)
Plasma NEFA (𝜇mol/L)
0 60 120 180 240 300
Time (min)
Plasma glycerol (𝜇mol/L)
F : Arterial plasma triglycerides (𝑝 = 0.0439) (a), NEFA (p = NS) (b), and glycerol (p = NS) (c) levels in subjects consuming vinegar
(V+) or placebo (V). At 𝑡=0min, a mixed meal was given.
was ingested with complex carbohydrates, but not with
monosaccharides [,]. Moreover, a previous study showed
that vinegar reduced postprandial glycaemia in patients with
glycaemic index meal [].
Glucose regulation depends mainly on insulin secretion
tissues. In our study, insulin levels were decreased aer
the consumption of vinegar, conrming previous reports
[,], suggesting that the hypoglycemic eect of vinegar
may be mediated through an eect on insulin action in the
peripheral tissues. Skeletal muscle is considered as the most
important tissue for insulin-stimulated glucose uptake [].
suggesting an improvement in insulin action in skeletal
muscle. It is well known that insulin aects vascular endothe-
lium and increases muscle and adipose tissue blood ow
by increasing vasodilation and capillary recruitment [
]. is eect is considered as an important component of
insulins stimulation of glucose uptake; impairment of this
mechanism in insulin-sensitive tissues may partly account
for insulin resistance in obesity and type  diabetes [,
]. Previous studies in nondiabetic humans suggest that
vinegar ingestion may enhance ow-mediated vasodilation
through endothelial nitric oxide synthase phosphorylation
[]. In addition, our previously published data on the eects
of vinegar on muscle blood ow in subjects with impaired
glucose tolerance have shown that vinegar ingestion before
ow rates aer the meal, although postprandial insulin levels
were decreased compared to their respective values in the
group consuming placebo []. However, in our study vinegar
ingestion did not alter muscle blood ow rates, suggesting
that the increase in glucose disposal aer meal ingestion may
not be attributed to a direct eect of vinegar on blood ow
in subjects with type  diabetes. A possible explanation for
this discrepancy between individuals with impaired glucose
tolerance and patients with type  diabetes could be that in
the early stages of glucose intolerance the defect of blood ow
may be reversible; however in overt type  diabetes the defect
in ow-mediated vasodilatation may be already established
and cannot be reversed by vinegar ingestion.
Journal of Diabetes Research
e eect of vinegar in the intracellular pathways of
examined in animal studies. In rats, acetic acid has been
shown to enhance glycogen repletion, attributed to accu-
mulation of glucose -phosphate due to suppression of
glycolysis []. e same eect has been reported in
horses aer exercise. In these studies acetate supplementation
enhanced the rate of muscle glycogen resynthesis during the
rst hours following the exercise period compared with the
control treatment []. Although the intracellular pathways
of glucose metabolism were not investigated in our study,
these in vitro studies suggest that the increase in glucose
uptake by the skeletal muscle following vinegar ingestion
could be explained by increased rates of glycogen synthesis.
In our study, vinegar ingestion decreased postprandial
hypertriglyceridaemia, without aecting NEFA and glycerol;
acute eects of vinegar on lipid metabolism in subjects with
type  diabetes. e eect of vinegar on lipid metabolism
has been investigated in several studies showing that chronic
administration of acetic acid reduces serum and hepatic
triglyceride levels [,,] in metabolically healthy animals.
In addition, chronically administered acetate treatment in
obese [] and/or type  diabetic []ratshasbeenshownto
result in a reduction of plasma triglyceride levels. In contrast,
triglyceride levels were not aected by acute administration
of  mL vinegar added to a hypercholesterolaemic diet in
rabbits []. On the other hand, information on humans
is limited to a few studies examining the chronic eect of
vinegar with conicting results. In these studies – mL
vinegar intake for – weeks resulted in a decrease of
hyperlipidaemia []. However, there was no eect of vinegar
intake in a prospective randomized, double blind, placebo-
controlled clinical study conducted in  nondiabetic sub-
jects consuming  mL apple vinegar for  weeks []. e
results of this study should however be considered with
caution since this study had several limitations; the most
important is the mixed group of subjects (one-third of the
participants were on statin and/or sh oil treatment).
Previous animal studies suggest that the eect of vinegar
of hepatic lipogenesis and increase of fatty acid oxidation
[,]. However, this mechanism could not explain the
results of the present study, since vinegar ingestion had no
acute eect on plasma levels of NEFA and glycerol. As a result,
although chronic administration of vinegar could have an
impact on fatty acid metabolism [,] our study showed
that the acute administration of vinegar in subjects with type
 diabetes does not aect lipolysis. A possible explanation
of these ndings could be that the acute intake of vinegar
increases insulin sensitivity of the adipose tissue, increasing
the lipoprotein lipase activity and the postprandial clearance
of triglycerides [,], with no eect on hormone-sensitive
lipase, which regulates lipolysis.
Although the arteriovenous dierence technique has
muscles, some limitations should be considered when inter-
preting the results. First, the number of participants was
relatively small. is was mainly due to the invasive nature
of the technique and the need for repeating the experiment
aer one week. However, due to the crossover design of
the study, our data were sucient for reaching statistical
signicance. Moreover, another limitation of our study was
that the patients had mild diabetes (HbAc: . ±.%). is
was due to the fact that we aimed to see the eect of vinegar
in patients with newly diagnosed diabetes, without diabetic
complications and without taking any medication therapy
that could aect glucose or lipid metabolism. Further studies
are needed to investigate the eect of vinegar on glucose
metabolism in patients with more severe type  diabetes, as
well as in those taking various treatments.
In summary, our study showed that, in type  diabetes,
vinegar reduces postprandial hyperglycaemia, hyperinsuli-
naemia, and hypertriglyceridaemia without aecting lipoly-
sis. As a result, vinegar’s eect on carbohydrate metabolism
in insulin-stimulated glucose uptake, demonstrating an
improvement in insulin action in the skeletal muscles. How-
ever, further studies are required to examine the long-term
eects of vinegar in type  diabetes.
Conflict of Interests
e authors declare that there is no conict of interests
regarding the publication of this paper.
e authors are grateful to E. Pappas and I. Kosmopoulou
for technical support and V. Frangaki, RN, for help with
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... During the literature search, 15 studies within 11 references were identified that investigated the effects of acute vinegar administration on glycemic control. These 15 studies were metaanalyzed (29-31, 33, 34, 38-43) for PBG responses in healthy individuals, with 7 in metabolically compromised individuals (31,32,(43)(44)(45). Five of the healthy volunteer studies (30,40,42,43) and 6 of the nonhealthy volunteer studies (32,(43)(44)(45) were also meta-analyzed for the postprandial insulin response. ...
... These 15 studies were metaanalyzed (29-31, 33, 34, 38-43) for PBG responses in healthy individuals, with 7 in metabolically compromised individuals (31,32,(43)(44)(45). Five of the healthy volunteer studies (30,40,42,43) and 6 of the nonhealthy volunteer studies (32,(43)(44)(45) were also meta-analyzed for the postprandial insulin response. ...
... In acute interventions, no AEs were reported for acetate nor vinegar (35,41,44,45). Two studies reported AEs for propionate interventions: 1 case of nausea was reported (57) and 1 study documented no AEs (54). ...
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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.
... The weight loss effect observed at week 10 of the study may occur through other mechanisms, such as increased hepatic fatty acid oxidation (37) , increased energy expenditure, (38) and increased insulin sensitivity. (39) Park JE et al. (37) who examined the effect of pomegranate vinegar on visceral fat in 78 overweight women, found that there was an increase in AMP-activated protein kinase (AMPK) activity in adipose tissue in the group who consumed pomegranate vinegar for eight weeks. Acetic acid is the active component found in all types of vinegar. ...
... p=0.0149). Mitrou P et al. (39) found an increase in insulin sensitivity in 11 subjects with type 2 diabetes mellitus who were given 30 mL of vinegar with 6% acetic acid content and 20 mL of water. Increased insulin sensitivity is characterized by decreased postprandial plasma insulin, glucose and triglyceride levels, and increased glucose uptake in striated muscle. ...
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LATAR BELAKANG Obesitas telah menjadi masalah global dalam sepuluh tahun terakhir. Angka kejadian obesitas yang terus bertambah menyebabkan meningkatnya jumlah kematian akibat berbagai penyakit terkait obesitas. Farmakoterapi obesitas yang ada saat ini terbatas dan memiliki berbagai efek samping. Cuka apel merupakan salah satu jenis bahan alamiah yang digunakan oleh masyarakat umum untuk menurunkan berat badan. METODE Penelitian ini merupakan penelitian eksperimental dengan menggunakan hewan coba. Sebayak 36 ekor tikus Spraque Dawley berusia 1-2 bulan diberikan diit tinggi lemak selama 5 minggu. Tikus dengan obesitas dibagi dalam 3 kelompok, yaitu kelompok kontrol, kelompok P1 yang diberi cuka apel dosis 0,096ml/100g/kali dan kelompok P2 yang diberi cuka apel dosis 0,192ml/100g/kali, masing-masing 2 kali sehari. Perlakuan diberikan selama 4 minggu. Berat badan dan sisa makanan ditimbang selama perlakuan. Data berat badan akhir dianalisa dengan uji Kruskal-Wallis dan selisih berat badan dianalisa dengan uji one-way ANOVA yang dilanjutkan dengan uji post hoc Turkey. HASIL Tidak ada perbedaan yang bermakna berat badan akhir antara 3 kelompok (p=0,55), namun terdapat perbedaan selisih berat badan bermakna antara kelompok kontrol dengan kelompok P1 (p=0,001) dan kelompok kontrol dengan kelompok P2 (p=0,000). KESIMPULAN Pemberian cuka apel dengan dua dosis berbeda pada penelitian ini memberikan efek penurunan berat badan pada tikus dengan obesitas
... In recent years, interest in vinegar's favorable metabolic effects has grown as a result of its positive effects. Acetic acid, organic acids, amino acids, peptides, vitamins, and mineral salts are all present in vinegar [80,81]. Vinegar's healthy beneficial role is mediated by the oxidation of low-density lipoproteins inhibition, leading to antidiabetic effects and lowering blood cholesterol levels [82,83]. ...
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Background: The use of herbs to treat illnesses was common in all historical eras. Our aim was to describe the phytotherapeutic substances that cancer patients use most commonly, and to determine whether their use can increase side effects. Methods: This was a retrospective and descriptive study conducted among older adults actively undergoing chemotherapy, admitted at the Oncology DH Unit (COES) of the Molinette Hospital AOU Città della Salute e della Scienza in Turin (Italy). Data collection was conducted through the distribution of self-compiled and closed-ended questionnaires during chemotherapy treatment. Results: A total of 281 patients were enrolled. Evaluating retching and sage consumption was statistically significant in multivariate analysis. The only risk factor for dysgeusia was chamomile consumption. Ginger, pomegranate, and vinegar use were retained as mucositis predictors. Conclusions: Phytotherapeutic use needs more attention in order to decrease the risks of side effects, toxicity, and ineffective treatment. The conscious administration of these substances should be promoted for safe use and to provide the reported benefits.
... Vinegar usage improves hyperinsulinaemia, hypertriglyceridaemia, insulin sensitivity and can also reduce the level of random blood glucose in diabetic patients as well as in healthy individuals [12]. Evidence of many studies showed that a single dose of vinegar (20 g) with 5% acidity can decrease PPG (post prandial glucose) in diabetic as well as in healthy individuals by 50% [6,13]. ...
... Of rode wijn, die ook het insulinegehalte verhoogt, maar niet zo veel als vis, en de rode wijn schiet ook triglyceriden omhoog, hoewel gedealcoholiseerde nietalcoholische rode wijn datzelfde probleem niet geeft [17]. Als we nog eens naar azijn kijken, kan niet alleen slechts 1 (één) eetlepel per dag de cholesterol en triglyceriden in de loop van de tijd verbeteren [18], maar azijn kan ook triglyceriden binnen een uur na een maaltijd verlagen, samen met het verlagen van de bloedsuikers en het verlagen van de insuline spike, en dus zodat azijn mogelijk het beste van alle werelden biedt in vergelijking met andere producten waaronder medicijnen [19]. ...
Full-text available
... A few clinical trials have also been conducted in individuals with prediabetes and/or T2DM. Vinegar intake before or together with a meal was associated with improved glycemia, reduced post-meal area under the curve for glucose, reduced fasting blood glucose, insulin and triglycerides, increased muscle glucose uptake, and reduced the need for fast-acting insulin in subjects with T1DM [398][399][400][401][402][403]. However, in another study, postprandial plasma glucose or insulin were unaffected by vinegar co-ingestion [404]. ...
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As years progress, we are found more often in a postprandial than a postabsorptive state. Chrononutrition is an integral part of metabolism, pancreatic function, and hormone secretion. Eating most calories and carbohydrates at lunch time and early afternoon, avoiding late evening dinner, and keeping consistent number of daily meals and relative times of eating occasions seem to play a pivotal role for postprandial glycemia and insulin sensitivity. Sequence of meals and nutrients also play a significant role, as foods of low density such as vegetables, salads, or soups consumed first, followed by protein and then by starchy foods lead to ameliorated glycemic and insulin responses. There are several dietary schemes available, such as intermittent fasting regimes, which may improve glycemic and insulin responses. Weight loss is important for the treatment of insulin resistance, and it can be achieved by many approaches, such as low-fat, low-carbohydrate, Mediterranean-style diets, etc. Lifestyle interventions with small weight loss (7–10%), 150 min of weekly moderate intensity exercise and behavioral therapy approach can be highly effective in preventing and treating type 2 diabetes. Similarly, decreasing carbohydrates in meals also improves significantly glycemic and insulin responses, but the extent of this reduction should be individualized, patient-centered, and monitored. Alternative foods or ingredients, such as vinegar, yogurt, whey protein, peanuts and tree nuts should also be considered in ameliorating postprandial hyperglycemia and insulin resistance. This review aims to describe the available evidence about the effects of diet, chrononutrition, alternative dietary interventions and exercise on postprandial glycemia and insulin resistance.
... Additionally, fruit by-products such as apple vinegar have been documented as having several biological properties due to its rich composition in phenolic compounds [30][31][32][33][34][35][36][37][38]. Apple vinegar is considered to be an antioxidant, antihyperglyceamic, antihyperlipidimic and hepato-nephroprotective agent [39][40][41][42]. Apple vinegar contains a large group of bioactive compounds with high antioxidant potential, which counteract reactive oxygen species (ROS) [43]. ...
Full-text available
This study aims to examine the ability of apple vinegar on phenylhydrazine (PHZ)-induced hemolytic anemia in Wistar rats. In vitro, phenolic and flavonoid content and antioxidant activity were determined. In vivo, phenylhydrazine (10 mg/kg) was injected intravenously into rats for 4 days and then treated with apple vinegar daily by gavage (1 mL/kg) for five weeks. high level of polyphenols and flavonoids (90 ± 1.66 mg GAE/100 mL and 7.29 ± 0.23 mg QE/100 mL, respectively) were found in the apple vinegar which gives it a good ability to scavenge free radicals (TAC = 4.22 ± 0.18 mg AAE/100 mL and DPPH, IC50= 0.49 ± 0.004 µL/mL). The phytochemical composition of apple vinegar revealed the presence of numerous bioactive compounds including arbutin, apig-enin, sinapic, ferulic and trans-ferulic acids. The major antioxidant components in apple vinegar were ferulic and trans-ferulic acids (40% and 43%, respectively). PHZ treatment induced changes in platelets, blood cell count, mean corpuscular volume, hemoglobin concentration and mean capsu-lated hemoglobin. However, the co-administration of apple vinegar revealed its capacity to ameliorate the changes induced by phenylhydrazine. Therefore, apple vinegar use could have a positive impact on the prevention of hemolytic anemia induced by phenylhydrazine due to the antioxidant properties of its major components.
... The inhibition of carbohydrate hydrolyzing enzymes could decrease postprandial hyperglycemia [34]. Numerous studies proved the ability of apple vinegar to reduce hyperglycemia [35][36][37][38]. In this context, the activity on α-glucosidase and α-amylase inhibition of the two samples of apple vinegar produced by different techniques were evaluated ( Table 4). ...
Full-text available
The main objective of the current study was to determine the physicochemical properties, antioxidant activities, and α-glucosidase and α-amylase inhibition of apple vinegar produced by artisanal and industrial methods. Apple vinegar samples were analyzed to identify their electrical conductivity, pH, titratable acidity, total dry matter, Brix, density, mineral elements, polyphenols, flavonoids, and vitamin C. The antioxidant activity of apple vinegar samples was evaluated using two tests, total antioxidant capacity (TAC) and DPPH radical scavenging activity. Finally, we determined α-glucosidase and α-amylase inhibitory activities of artisanal and industrial apple vinegar. The results showed the following values: pH (3.69–3.19); electrical conductivity (2.81–2.79 mS/cm); titratable acidity (3.6–5.4); ash (4.61–2.90); ◦Brix (6.37–5.2); density (1.02476–1.02012), respectively, for artisanal apple vinegar and industrial apple vinegar. Concerning mineral elements, potassium was the most predominant element followed by sodium, magnesium, and calcium. Concerning bioactive compounds (polyphenols, flavonoids, and vitamin C), the apple vinegar produced by the artisanal method was the richest sample in terms of bioactive compounds and had the highest α-glucosidase and α-amylase inhibition. The findings of this study showed that the quality and biological activities of artisanal apple vinegar were more important than industrial apple vinegar
... They posess alkali component that decomposes lactic acid in body tissues and helps to energize the body (Atik et al., 2016;Choi et al., 2013), and the sour flavor improves appetite, digestion and absorption (Jeong et al., 2011). On addition, vinegar increases the removal of sodium and silicic acid from the body and it is known to be effective in preventing or treating fever, swelling, stomach ache and metabolic complications, such as high blood pressure, atherosclerosis, insulin resistance, and hyperlipidemia (Budak et al., 2014;Mitrou et al., 2015). According to Adam et al. (2004) organic acids are considered weak acids meaning the antimicrobial effect of organic acids is mainly caused by its undissociated forms. ...
Although vinegar has been consumed since ancient times, the demand for developing this product from unconventional fruits has increased in recent years. Therefore, the goal of this study was to evaluate the perception of consumers in the South Region of Brazil regarding vinegar and explore the potential of regional raw materials for its production. The study was carried out with a total of 1,970 participants using an online questionnaire divided into five sections. Through word association technique, it was noted that age group influenced on the perception experienced by those participants who are regular consumers of vinegar regarding its attributes and properties. Moreover, the type of vinegar consumed was correlated with the income of the participants. Moreover, some fruits native to the South Region of Brazil, such as jaboticaba, orange passion fruit, red araçá, uvaia, guabiroba, and feijoa, showed great potential for application in vinegar production. This study identified the factors that influence on consumer perception experienced by people who regularly consume vinegar, as well as their attitudes related to its use, consumption, and application. Besides, it showed the importance of applying new raw materials in the vinegar preparation process, highlighting the potential of native fruits from the South Region of Brazil, thus providing relevant information for the vinegar market and an opportunity for the development of new products.
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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.
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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.
The aim of this review is to summarize the effects of vinegar on glucose and lipid metabolism. Several studies have demonstrated that vinegar can help reduce hyperglycemia, hyperinsulinemia, hyperlipidemia, and obesity. Other studies, however, have shown no beneficial effect on metabolism. Several mechanisms have been proposed to explain these metabolic effects, including delayed gastric emptying and enteral absorption, suppression of hepatic glucose production, increased glucose utilization, upregulation of flow-mediated vasodilation, facilitation of insulin secretion, reduction in lipogenesis, increase in lipolysis, stimulation of fecal bile acid excretion, increased satiety, and enhanced energy expenditure. Although some evidence supports the use of vinegar as a complementary treatment in patients with glucose and lipid abnormalities, further large-scale long-term trials with impeccable methodology are warranted before definitive health claims can be made.
The aim of this study was to investigate the effects of persimmon-vinegar supplementation on blood lipid profiles, carnitine concentrations, and hepatic mRNA levels of enzymes involved in fatty acid metabolism. Thirty-two C57BL/6J male mice were divided into 4 groups; control group (HD), industrial vinegar group (HD-V), and persimmon-vinegar groups (HD-PV1, HD-PV2). Serum triglyceride (TG) and total cholesterol (TC) concentrations significantly decreased in all vinegar-administered groups compared with the HD group. The hepatic TG and TC concentrations of persimmon-vinegar administered groups were significantly lower compared with the HD group. Liver acid insoluble acylcarnitine (AIAC) was significantly higher in the HD-PV2 than in HD and HD-V groups. The acetyl-CoA carboxylase (ACC) mRNA level tended to lower in all the vinegar administered groups compared with the HD group. These results suggest that the persimmon-vinegar has anti-obesity properties. Keywordspersimmon-vinegar-mice-lipid profile-carnitine-hepatic mRNA level
In type 2 diabetes, although the impairment of postprandial muscle blood flow response is well established, information on the effect of this impairment on glucose uptake and lipid metabolism is controversial. Postprandial forearm blood flow responses and metabolic parameters were assessed in a cross-sectional study of subjects at various stages of insulin resistance. Eleven healthy subjects (CONTROLS), 11 first-degree relatives of type-2 diabetics (RELATIVES), 10 patients with impaired glucose tolerance (IGT), 10 diabetic patients with postprandial hyperglycaemia (DMA), and 13 diabetic patients with both fasting and postprandial hyperglycaemia (DMB). All subjects received a meal. Blood was drawn from a forearm deep vein and the radial artery at specific time-points during a period of 360 min for measurements of glucose, insulin, triglycerides and nonesterified-fatty acids. Forearm muscle blood flow was measured with strain-gauge plethysmography. Glucose uptake and ISI Index were calculated. Peak-baseline muscle blood flow was higher in CONTROLS (3.32 ± 0.4) than in RELATIVES (0.53 ± 0.29), IGT (0.82 ± 0.2), DMA (1.44 ± 0.34), DMB (1.23 ± 0.35 ml/min/100 ml tissue), P < 0.001. Glucose uptake (AUC(0-360,) μmol/100 ml tissue) was higher in CONTROLS (1023 ± 132) than in RELATIVES (488 ± 42), IGT (458 ± 43), DMA (347 ± 63), DMB (543 ± 53), P < 0.001. ISI index, postprandial triglycerides and nonesterified-fatty acids behaved in a similar way. Peak-baseline muscle blood flow correlated positively with glucose uptake (r = 0.440, P = 0.001) and ISI index (r = 0.397, P = 0.003), and negatively with postprandial triglycerides (r = -0.434, P = 0.001) and nonesterified-fatty acids (r = -0.370, P = 0.005). These results suggest that increase in muscle blood flow after a meal is impaired at all stages of type-2 diabetes. This defect influences glucose uptake and is associated with impaired lipid metabolism in the postprandial state.
Hyperthyroidism leads to an enhanced demand for glucose, which is primarily provided by increased rates of hepatic glucose production due to increased gluconeogenesis (in the fasting state) and increased Cori cycle activity (in the late postprandial and fasting state). Adipose tissue lipolysis is increased in the fasting state, resulting in increased production of glycerol and nonesterified fatty acids. Under these conditions, increased glycerol generated by lipolysis and increased amino acids generated by proteolysis are used as substrates for gluconeogenesis. Increased nonesterified fatty acid levels are necessary to stimulate gluconeogenesis and provide substrate for oxidation in other tissues (such as muscle). In the postprandial period, insulin-stimulated glucose uptake by the skeletal muscle has been found to be normal or increased, mainly due to increased blood flow. Under hyperthyroid conditions, insulin-stimulated rates of glycogen synthesis in skeletal muscle are decreased, whereas there is a preferential increase in the rates of lactate formation vs. glucose oxidation leading to increased Cori cycle activity. In hyperthyroidism, the Cori cycle could be considered as a large substrate cycle; by maintaining a high flux through it, a dynamic buffer of glucose and lactate is provided, which can be used by other tissues as required. Moreover, lipolysis is rapidly suppressed to normal after the meal to facilitate the disposal of glucose by the insulin-resistant muscle. This ensures the preferential use of glucose when available and helps to preserve fat stores.