ArticleLiterature Review

Cinnamon Intake Lowers Fasting Blood Glucose: Meta-Analysis

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Abstract

Cinnamon, the dry bark and twig of Cinnamomum spp., is a rich botanical source of polyphenolics that has been used for centuries in Chinese medicine and has been shown to affect blood glucose and insulin signaling. Cinnamon's effects on blood glucose have been the subject of many clinical and animal studies; however, the issue of cinnamon intake's effect on fasting blood glucose (FBG) in people with type 2 diabetes and/or prediabetes still remains unclear. A meta-analysis of clinical studies of the effect of cinnamon intake on people with type 2 diabetes and/or prediabetes that included three new clinical trials along with five trials used in previous meta-analyses was done to assess cinnamon's effectiveness in lowering FBG. The eight clinical studies were identified using a literature search (Pub Med and Biosis through May 2010) of randomized, placebo-controlled trials reporting data on cinnamon and/or cinnamon extract and FBG. Comprehensive Meta-Analysis (Biostat Inc., Englewood, NJ, USA) was performed on the identified data for both cinnamon and cinnamon extract intake using a random-effects model that determined the standardized mean difference ([i.e., Change 1(control) - Change 2(cinnamon)] divided by the pooled SD of the post scores). Cinnamon intake, either as whole cinnamon or as cinnamon extract, results in a statistically significant lowering in FBG (-0.49±0.2 mmol/L; n=8, P=.025) and intake of cinnamon extract only also lowered FBG (-0.48 mmol/L±0.17; n=5, P=.008). Thus cinnamon extract and/or cinnamon improves FBG in people with type 2 diabetes or prediabetes.

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... Our initial search identified 2,363 articles after removing duplicates ( Figure 1). Forty-nine full texts were screened and of these, 25 met all our inclusion criteria (Davis and Yokoyama, 2011;Kim et al., 2011;Leach and Kumar, 2012;Ooi et al., 2012;Allen et al., 2013;Ooi and Loke, 2013;Neelakantan et al., 2014;Gibb et al., 2015;Gui et al., 2016;Li et al., 2016;Shin et al., 2016;Suksomboon et al., 2016;Tian et al., 2016;Zhang et al., 2016;Daryabeygi-Khotbehsara et al., 2017;Poolsup et al., 2017;Schwingshackl et al., 2017;Gu et al., 2018;Deyno et al., 2019;Gao et al., 2019;Huang et al., 2019;Namazi et al., 2019;Peter et al., 2019;Yang et al., 2019;Ziaei et al., 2020). The commonest reason for exclusion was that the review did not attempt a quantitative meta-analysis of randomised controlled trials. ...
... There were reviews on 18 different medicinal plants ( Table 1). Some herbal remedies had more than one review: cinnamon (Davis and Yokoyama, 2011;Leach and Kumar, 2012;Allen et al., 2013;Deyno et al., 2019;Namazi et al., 2019), ginseng (Kim et al., 2011;Gui et al., 2016), Aloe vera (Suksomboon et al., 2016;Zhang et al., 2016) and karela (Momordica charantia) (Ooi et al., 2012;Peter et al., 2019). Three reviews evaluated the effect of a standard traditional Chinese herbal formula which contained a mixture of several herbs. ...
... There were varying results in the five meta-analyses of cinnamon, but the largest and most recent (which only included patients with T2DM) showed a clinically significant reduction in FPG of −1.07 mmol/l (95% CI-1.56 to −0.58) (Namazi et al., 2019). Other reviews also included patients with T1DM (Leach and Kumar, 2012) or pre-diabetes (Davis and Yokoyama, 2011;Deyno et al., 2019). ...
... Our initial search identified 2,363 articles after removing duplicates ( Figure 1). Forty-nine full texts were screened and of these, 25 met all our inclusion criteria (Davis and Yokoyama, 2011;Kim et al., 2011;Leach and Kumar, 2012;Ooi et al., 2012;Allen et al., 2013;Ooi and Loke, 2013;Neelakantan et al., 2014;Gibb et al., 2015;Gui et al., 2016;Li et al., 2016;Shin et al., 2016;Suksomboon et al., 2016;Tian et al., 2016;Zhang et al., 2016;Daryabeygi-Khotbehsara et al., 2017;Poolsup et al., 2017;Schwingshackl et al., 2017;Gu et al., 2018;Deyno et al., 2019;Gao et al., 2019;Huang et al., 2019;Namazi et al., 2019;Peter et al., 2019;Yang et al., 2019;Ziaei et al., 2020). The commonest reason for exclusion was that the review did not attempt a quantitative meta-analysis of randomised controlled trials. ...
... There were reviews on 18 different medicinal plants ( Table 1). Some herbal remedies had more than one review: cinnamon (Davis and Yokoyama, 2011;Leach and Kumar, 2012;Allen et al., 2013;Deyno et al., 2019;Namazi et al., 2019), ginseng (Kim et al., 2011;Gui et al., 2016), Aloe vera (Suksomboon et al., 2016;Zhang et al., 2016) and karela (Momordica charantia) (Ooi et al., 2012;Peter et al., 2019). Three reviews evaluated the effect of a standard traditional Chinese herbal formula which contained a mixture of several herbs. ...
... There were varying results in the five meta-analyses of cinnamon, but the largest and most recent (which only included patients with T2DM) showed a clinically significant reduction in FPG of −1.07 mmol/l (95% CI-1.56 to −0.58) (Namazi et al., 2019). Other reviews also included patients with T1DM (Leach and Kumar, 2012) or pre-diabetes (Davis and Yokoyama, 2011;Deyno et al., 2019). ...
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Aims: To rank the effectiveness of medicinal plants for glycaemic control in Type 2 Diabetes (T2DM). Methods: MEDLINE, EMBASE, CINAHL and Cochrane Central were searched in October 2020. We included meta-analyses of randomised controlled clinical trials measuring the effectiveness of medicinal plants on HbA1c and/or Fasting Plasma Glucose (FPG) in patients with T2DM. Results: Twenty five meta-analyses reported the effects of 18 plant-based remedies. Aloe vera leaf gel, Psyllium fibre and Fenugreek seeds had the largest effects on HbA1c: mean difference –0.99% [95% CI−1.75, −0.23], −0.97% [95% CI −1.94, −0.01] and −0.85% [95% CI −1.49, −0.22] respectively. Four other remedies reduced HbA1c by at least 0.5%: Nigella sativa , Astragalus membranaceus, and the traditional Chinese formulae Jinqi Jiangtang and Gegen Qinlian. No serious adverse effects were reported. Several other herbal medicines significantly reduced FPG. Tea and tea extracts ( Camellia sinensis ) were ineffective. However, in some trials duration of follow-up was insufficient to measure the full effect on HbA1c (<8 weeks). Many herbal remedies had not been evaluated in a meta-analysis. Conclusion: Several medicinal plants appear to be as effective as conventional antidiabetic treatments for reducing HbA1c. Rigorous trials with at least 3 months’ follow-up are needed to ascertain the effects of promising plant-based preparations on diabetes.
... A number of herbs have been used to manage symptoms related to deleterious changes in glucose metabolism [10][11][12][13][14][15][16][17]. A number of clinical studies of herbal interventions (i.e., cinnamon, fenugreek, banaba, curcumin, and others) conducted among adult populations with prediabetes have demonstrated improved glycemic control, particularly with regard to reducing fasting blood glucose [18][19][20][21][22][23][24][25] and postprandial glucose [18,22,[26][27][28][29], HbA 1c [25,30,31], fasting insulin levels [9,26,[28][29][30][31], homeostatic model of Insulin Resistance (HOMA-IR) [20,28,30,32,33], and increasing homeostatic model of β-cell function (HOMA-β) [27,32]. Substantial changes in glycemic parameters typically occur within 12 weeks [34,35]. ...
... Several herbs have also demonstrated benefit in glycemic control in clinical trials among T2D populations. These herbs and herbal extracts include berberine [37][38][39], ginseng [40,41], gymnema [42,43], banaba [44], cinnamon [24,45], fenugreek [46], and kudzu [47]. Of these, some have also demonstrated potential benefit for promoting positive changes in lipid markers [37,[48][49][50][51][52][53][54][55][56][57][58][59][60]. ...
... GlucoSupreme™ Herbal (Designs for Health®, Suffield, CT, USA) is a polyherbal formula for glycemic control which contains many of the herbs and their standardized extracts that have been previously studied and shown to be potentially efficacious for glycemic control [24,[37][38][39][40][41][42][43][44][45][46][47]. This supplement has been commercially available in the United States since 2009. ...
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Article
Background Prediabetes describes a state of hyperglycemia outside of normal limits that does not meet the criteria for diabetes diagnosis, is generally symptomless, and affects an estimated 38% of adults in the United States. Prediabetes typically precedes the diagnosis of type 2 diabetes, which accounts for increased morbidity and mortality. Although the use of dietary and herbal supplements is popular worldwide, and a variety of single herbal medicines have been examined for glycemic management, the potential of increasingly common polyherbal formulations to return glycemic parameters to normal ranges among adults with prediabetes remains largely unexplored. The purpose of this study is to evaluate the efficacy of a commercially available, polyherbal dietary supplement on glycemic and lipid parameters in prediabetic individuals. Methods In this multi-site, double-blinded, randomized controlled clinical trial, 40 participants with prediabetes will be randomized to either a daily oral polyherbal dietary supplement (GlucoSupreme™ Herbal; Designs for Health®, Suffield, CT, USA; containing cinnamon bark (Cinnamomum cassia), banaba leaf (Lagerstroemia speciosa standardized to 1% corosolic acid), kudzu root (Pueraria lobata standardized to 40% isoflavones), fenugreek seed (Trigonella foenum-graceum standardized to 60% saponins), gymnema leaf (Gymnema sylvestre standardized to 25% gymnemic acid), American ginseng root (Panax quinquefolius standardized to 5% ginsenosides), and berberine HCl derived from bark (Berberis aristata)) or placebo for 12 weeks. Short-, medium-, and comparatively long-term markers of glycemic control (blood glucose and fasting insulin, fructosamine, and glycated hemoglobin/A1c, respectively), and other glycemic parameters (GlycoMark, β-cell function, and insulin sensitivity/resistance) will be obtained. Lipid profile (total cholesterol, LDL, HDL, and triglycerides), inflammation (hs-CRP), progression to type 2 diabetes mellitus, as well as safety indices (ALT, AST) will be obtained. An intention-to-treat analysis will be used to assess changes in study outcomes. Discussion Treatment options for adults with prediabetes are currently limited. This study aims to evaluate the safety and efficacy of a commercially available dietary supplement in the popular, but as yet insufficiently studied, category of polyherbal formulas for the management of glycemic parameters and other biomarkers associated with prediabetes. Trial registration ClinicalTrials.gov, ID: NCT03388762. Retrospectively registered on 4 January 2018. Electronic supplementary material The online version of this article (10.1186/s13063-018-3032-6) contains supplementary material, which is available to authorized users.
... In general, the studies ranged from 4 to 16 weeks, counting 186 people in the group receiving cinnamon and 183 in the control group. This time, both the cinnamon powder intake and the extract decreased fasting blood glucose, demonstrating a reduction about 9 mg/dL [30]. ...
... Akilen et al. (2012) selected 6 clinical trials for meta-analysis, containing 435 patients, in which the tests lasted from 40 days to 4 months and the use of cinnamon from 1 to 6 g/d. In accordance with Davis e Yokoyama [30], this meta-analysis also excluded the Altschuler et al. study [26]. As a resulted, the cinnamon supplementation showed decreases of HbA1c and fasting glycaemia levels [10]. ...
... Cinnamon supplementation ranged from 120 mg to 6 g (including aqueous extract and powder cinnamon) daily with a treatment interval of 4e18 weeks [31]. However, like most aforementioned meta-analysis [10,25,30], there was no rigorous for separating hypoglycemic and hypolipidemic medicines from cinnamon potential [31]. ...
Article
Background & aims: Cinnamon is a condiment used in cooking and by some in large quantities as a supplement with purported hypoglycemic and lipid-lowering potential. The current literature review aims to discuss the evidence of cinnamon administration regarding its hypoglycemic and lipid-lowering effects, summarizing clinical recommendations. Methods: Electronic databases including PubMed, Cochrane library, Science Direct and Web of Science were searched with the scientific name of the plant as well as the common name. The search for articles was based on following keywords: "cinnamon diabetes", "cinnamon diabetes type 2", "cinnamon and diabetes type 2", "Cinnamomum aromaticum", "Cinnamomum cassia", "Cinnamomum verum", "Cinnamomum zeylanicum". We carried out inclusion criteria between 2003 and 2018 focusing on human studies. Results: Concerning glycemic profile, in individuals with type II diabetes mellitus the fasting blood glucose reduced from 12.9 to 52.2 mg/dL and HbA1c from 0.27 to 0.83%, whereas serum insulin decreased in few studies. Research papers ranged from 6 to 17 weeks in duration. The lipid lowering potential, in turn, is most controversial compared to anti-hyperglycemic potential. Also cinnamon administration has been claimed to reduce fat mass and raise serum antioxidants, but the studies used inaccurate methods. Two species are most investigated, C. cassia/aromaticum, and C.zeylanicum/verum. Conclusions: About 1-6 g of these cinnamon species mainly in powder seems to be an adjunct drug treatment for type 2 diabetes mellitus and other conditions of glycemic impairment. However, more controlled clinical trials are needed.
... Eight systematic reviews and meta-analyses have investigated the effect of cinnamon on markers of glycemic control (Table 2). 44,45,[47][48][49][50][51][52] In the most recent meta-analysis, which was published in 2019 and included 16 RCTs of people with prediabetes and type 2 diabetes, cinnamon supplementation of 1-14.4 g/day reduced fasting glucose levels (WMD, -9.82 mg/dL; 95%CI, -16.40 to -3.24; I 2 ¼ 83.6%) and HOMA-IR (WMD, -0.71; 95%CI, -1.39 to -0.04; ...
... A meta-analysis that included healthy participants as well as those with type 2 diabetes or prediabetes showed cinnamon supplementation for 4-16 weeks lowered fasting blood glucose levels (SMD, -8.77 mg/dL). 51 Finally, authors of a 2012 Cochrane review that included 10 RCTs involving participants with type 1 or type 2 diabetes (n ¼ 577) concluded that cinnamon supplementation was no more effective than placebo, other active treatments, or no treatment for reducing fasting glucose, insulin, or HbA1c levels. 50 Of the 10 included studies, 2 were assessed as being at moderate risk of bias and 8 studies had an unclear risk of bias. ...
Article
Herbs and spices are recommended to increase flavor and displace salt in the diet. Accumulating evidence suggests herbs and spices may improve risk factors for cardiometabolic diseases. In this narrative review, an overview of evidence from human clinical trials examining the effect of herbs and spices on risk factors for cardiometabolic diseases is provided. Human clinical trials examining supplemental doses of individual spices and herbs, or the active compounds, have yielded some evidence showing improvements to lipid and lipoprotein levels, glycemic control, blood pressure, adiposity, inflammation, and oxidative stress. However, cautious interpretation is warranted because of methodological limitations and substantial between-trial heterogeneity in the findings. Evidence from acute studies suggests intake of mixed herbs and spices as part of a high-saturated fat, high-carbohydrate meal reduces postprandial metabolic impairments, including lipemia, oxidative stress, and endothelial dysfunction. Limited studies have examined the postprandial metabolic effects of incorporating mixed herbs and spices into healthy meals, and, to our knowledge, no trials have assessed the effect of longer-term intake of mixed herbs and spices on risk factors for cardiometabolic diseases. To inform evidence-based guidelines for intake of herbs and spices for general health and cardiometabolic disease risk reduction, rigorously conducted randomized controlled trials are needed, particularly trials examining herb and spice doses that can be incorporated into healthy dietary patterns.
... Previous clinical studies and three of four recent meta-analyses have reported beneficial effects of long-term cinnamon intake on blood glucose homeostasis in people with normal glucose homeostasis and varying degrees of glucose intolerance including type 2 diabetes (1)(2)(3)(4). For example, in subjects with type 2 diabetes given 1, 3, or 6 g of ground cinnamon per day for 40 days showed significant reductions in fasting serum glucose (18 ∼ 29%), triglycerides (23 ∼ 30%), LDL cholesterol (7 ∼ 27%), and total cholesterol (12 ∼ 26%) with no significant changes in the placebo group (5). ...
... The health benefit of long-term cinnamon consumption has been previously evaluated (1)(2)(3)(4)(5)22). In Type 2 diabetes, the glucose lowering effects of long-term cinnamon supplementation has been consistently reported (22,23). ...
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Article
Clinical studies and meta-analyses have supported the notion that consuming cinnamon spice long term can have beneficial effects in individuals with normal glucose homeostasis and varying degrees of glucose intolerance including type 2 diabetes. The objective of this study was to evaluate the acute effect of cinnamon on the post-prandial responses to a typical American breakfast in normal and overweight/obese participants (ClinicalTrials.gov registration No. NCT04686552). The consumption of a single dose of 6 g of cinnamon added to oatmeal prepared with milk resulted in a significant reduction of one of our primary outcomes post-prandial insulin response (niAUC0−180min) in overweight/obese participants compared to control consuming breakfast without cinnamon. We also performed exploratory analysis of secondary outcomes. In normal weight participants, we observed a decrease of post-prandial glucagon response (niAUC0−180min and glucagon levels at 60–120 min) and C-peptide response (30 min) comparing breakfast with to without cinnamon. Cinnamon consumption did not change post-prandial glycemic response in normal weight participants, but increased 60 min post-prandial glucose in overweight/obese participants compared to control. In summary, cinnamon consumption differentially affected post-prandial hormonal responses in normal and overweight/obese participants.
... Cinnamon is a dietary component that has been demonstrated to include biologically active substances that regulate blood glucose by insulin-mimetic properties (23). Several clinical trials exhibited that Cinnamon and its extracts achieved a therapeutic effect on diabetic patients (24,25). In clinical trials, cinnamon displayed positive effects on glycemic control lipid markers in type 2 diabetes populations (24,26). ...
... Several clinical trials exhibited that Cinnamon and its extracts achieved a therapeutic effect on diabetic patients (24,25). In clinical trials, cinnamon displayed positive effects on glycemic control lipid markers in type 2 diabetes populations (24,26). In light of the previous data supporting cinnamon dietary supplement improves glycemic parameters. ...
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Article
Cinnamomum cassia (Cinnamon) is a well-known traditional medicine with therapeutic benefits for centuries. We evaluated the effects of cinnamon essential oil (CEO) and its main component cinnamaldehyde (CA) on human corpus cavernosum (HCC) and rat CC. The essential oil of cinnamon was analyzed for the confirmation of the oil profile. HCC specimens from patients undergoing penile prosthesis surgery (age 48-69 years) were utilized for functional studies. In addition, erectile responses in anesthetized control and diabetic rats were evaluated in vivo after intracavernosal injection of CEO and CA, and rat CC strips were placed in organ baths. After precontraction with phenylephrine (10μM), relaxant responses to CEO and CA were investigated. CA (96.9%) was found as the major component. The maximum relaxation responses to CEO and CA were 96.4±3.5% and 96.0±5.0% in HCC and 97.5±5.5% and 96.8±4.8% in rat CC, respectively. There was no difference between control and diabetic rats in relaxation responses to CEO and CA. The relaxant responses obtained with essential oil and CA were not attenuated in the presence of nitric oxide synthase (NOS) inhibitor, and soluble guanylate cyclase inhibitor (sGS) in CC. In vivo, erectile responses in diabetic rats were lower than in control rats, which was restored after intracavernosal injection of CEO and CA. CEO and CA improved erectile function and relaxation of isolated strips of rat CC and HCC by a NO/cGMP-independent mechanism. Further investigations are warranted to fully elucidate the restorative effects of CEO and CA on diabetic erectile dysfunction.
... Cinnamon is one of the most ancient spices still in common use, and has been written about since antiquity (Singh et al., 2007). It is also one of the 98 common foods analyzed by the U.S. Department of Agriculture scientists and is widely used in medicine for its strong antioxidant activity (Davis & Yokoyama, 2011). Rose flowers are traditional Chinese folk medicine and ornamental plants. ...
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Article
Excessive oxygen free radicals can lead to aging, cancer, and other diseases. Therefore, searching for effective antioxidants to scavenge oxygen free radicals has become the focus of modern medicine. In this study, the molecular mechanism of Licorice Green Tea Beverage (LGTB) in scavenging oxygen free radicals was investigated by means of network pharmacology, molecular docking and experimental verification. Network pharmacology studies have shown that paeonol, eugenol, cinnamaldehyde, swertisin, rutin, glycyrrhetinic acid, oleic, pelargonidin‐3‐O‐glucoside and quercetin, kaferempol were the main active components of LGTB, and SOD and CAT are important targets for LGTB in scavenging oxygen free radicals. The results of molecular docking showed that these representative compounds had good affinity to SOD and CAT target proteins. In vitro free radical scavenging experiments showed that LTGB had significant scavenging effects on both DPPH and ABTS radicals, and had strong total reducing power. In vitro cell experiments showed that LGTB could protect HaCaT cells from oxidative stress induced by H2O2. The mechanism of LGTB was related to the increase of SOD and CAT activity. Western blotting showed that LGTB could inhibit PI3K/AKT/HIF‐1 signaling pathway and improve the antioxidant capacity of HaCaT cells. In vivo experiments showed that LGTB could significantly increase mouse visceral index, increase serum SOD and GSH‐Px activity, decrease the content of MDA, and improve liver and kidney pathological state. This study reported the molecular mechanism of LTGB scavenging oxygen free radicals, which provided scientific basis for the treatment and clinical research of aging and other diseases caused by excessive free radicals. Practical applications Free radicals are produced by the normal response of cells during aerobic respiration and perform various functions, such as signaling and providing protection against infection. However, excessive free radicals can lead to aging, cancer, and other diseases. The antioxidant can overcome the harm caused by excessive free radicals. In this study, we investigated the molecular mechanism of scavenging oxygen free radicals of Licorice Green Tea Beverage (LGTB) through network pharmacology and molecular docking, and its efficacy was verified by free radical scavenging experiment in vitro, HaCaT cell oxidative stress injury induced by H2O2, D‐galactose to establish an aging model in mice and Western blotting experiment. It not only elucidates its mechanism at the system level, but also proves its validity at the biological level. It provides the theoretical basis and experimental evidence for the follow‐up research and promotion of the product.
... At present, Cinnamon is available within the market as a prophylactic supplement for metabolic syndrome, insulin resistance and Type 2 diabetes mellitus [40]. Some clinical trials exhibited that Cinnamon and its extracts achieved a therapeutic effect on diabetic patients [18,41,42]. ...
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Article
Cinnamon has been used for centuries as a flavor ingredient and for medicinal purposes. It is known to reduce the risk of cancers, hyperlipidemia, and hyperglycemia due to the presence of a variety of functional active compounds. Major active components available in Cinnamon are cinnamaldehyde, cinnamyl acetate, cinnamyl alcohol, eugenol, tannin, methyl-hydroxy chalcone polymer (MHCP), cinnamic acid, camphor, etc. Among the commonly cultivated cinnamon species; Cinnamon verum or Cinnamomum zeylanicum, known as Ceylon cinnamon, has been identified as superior in beneficial active compound composition compared to its counterpart C. cassia. Various parts of the cinnamon plant such as bark, roots, and leaves contain different compositions of active compounds. Hence, their extractions are in medicinal use. Cinnamon oils and oleoresins are frequently used in the food industry due to their flavor and health benefits. Cinnamon is proven to reduce low-density lipoprotein and serum triglyceride contents effectively. High antioxidant properties are assumed to reduce the risk of cancers of various types. The antimicrobial properties of cinnamon extracts are often considered in Asian endemic medicinal treatments and are clinically proven. Among all, the remarkable ability of cinnamon in increasing insulin sensitivity and thereby, reducing the risk of type 2 diabetes has is a highlight.
... Herbs and spices regulate blood pressure, lower total cholesterol level, reduce the risk of atherosclerosis, and have anti-diabetic properties (ginger, cinnamon, bay leaf, mustard) [16][17][18][19][20][21][22]. They are used as antiseptic, antiviral, antifungal, antibacterial, antiinflammatory, painkillers (ginger, marjoram, oregano, thyme, rosemary, lemon balm, sage, cloves, parsley leaf, cayenne pepper) [14,[23][24][25]. ...
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Article
In this study, the content of total polyphenols (TP) and the antioxidant activity (AA) of fresh herbs (13 in total) and those subjected to the freeze-drying process (stems and leaves separately) were compared. Moreover, the content of TP and AA of retail, commercial food spices (19 in total) of the two leading companies on the Polish market were compared. The novelty of our studies is the comparison between fresh and dried forms of herbs and spices and additionally between dried in a freeze-drying process and commercially available (in dried forms). It was found that fresh herbs and spices showed a large accumulation of polyphenolic compounds (from 466.55 to 17.23 CAE/100 g, respectively, for lemon balm and ginger). For freeze-dried herbs and spices, the highest TP content was found for marjoram (3052.34 CAE/100 g—leaves). Among commercial herbs and spices, sage (971.28 CAE/100 g) deserves attention. Fresh herbal spices, in particular oregano, (236.21 µM TE/g) had the highest AA. AA of freeze-dried herbs and spices was much lower (5.27–1.20 µM TE/g). The average value obtained for commercially available herbs and spices purchased was 1.44 µM TE/g. In the case of AA measured by the DPPH radical, thyme was characterized by the highest activity among fresh marjoram for freeze-dried herbs and spices. For dried commercial spices, the highest levels of AA were found for cumin.
... Davis PA et al. found cinnamon intake, either as whole cinnamon or as a cinnamon extract, was statistically significant in lowering FBG (-0.49±0.2 mmol/L; n=8, P=.025) in their comprehensive meta-analysis (Biostat Inc.) in the year 2011 [23]. But Leach MJ et al. [24] and Baker et al. [25] found cinnamon to be no more effective than placebo, another active medication, or no treatment in reducing glucose levels and glycosylated hemoglobin A1C (HbA1c) in their systematic review. ...
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Article
Control of diabetes is a constant challenge and natural remedies are being searched along with modern medicine. The effectiveness of cinnamon in managing it lacks consensus. Besides this, earlier trials had a variant in the type of product they used, quantity, duration, the form of molecules, etc. So, we aimed to measure the impact of cassia ground bark powder consumption, 1-2 gm/day for 90 days, in lowering plasma glucose and lipids among those with type 2 diabetes. The authors searched the PubMed, Medline, Embase, CINAHL, Clinical Key, Ovid, and Scopus databases and the Cochrane Central Register (last search December 30, 2020) with the MeSH terms and keywords of cinnamon, cassia cinnamon, Chinese cinnamon, and type 2 diabetes mellitus to conclude the effects of cassia cinnamon on diabetes based on the evidence of human clinical trials that reported at least one of the following: glycosylated hemoglobin (HbA1C), fasting blood glucose, total cholesterol, triglycerides, low-density lipoprotein (LDL), and high-density lipoprotein (HDL). Weighted mean differences were calculated by using the random-effect model of RevMan software (The Cochrane Collaboration, London, UK), and the pooled analysis found an insignificant reduction of the outcome variable (p>0.05).
... There have been many benefits claimed in the literature and a few extended into phase I and II clinical trials. The list includes (1) lowering of blood glucose(Akilen et al., 2010(Akilen et al., , 2013Crawford et al., 2016;Davis & Yokoyama, 2011;Ranasinghe et al., 2017;Zhu et al., 2017); (2) blood pressure control(Akilen et al., 2010(Akilen et al., , 2013Azimi et al., 2016); (3) lowering of serum cholesterol(Chatterji & Fogel, 2018;Gupta et al., 2017;Maierean et al., 2017); (4) antimicrobial activity(Condo et al., 2018;Husain et al., 2018;Mamajiwala et al., 2018;Rangel et al., 2018;Raybaudi-Massilia et al., 2006;Sethi et al., 2019;Shahina et al., 2018); (5) antiparasitic activity(Yang et al., 2014); (6) antioxidative properties and related free radical scavenging action(Dhuley, 1999;Khaki et al., 2014;Panickar et al., 2009;Ranasinghe et al., 2013;Shahid et al., 2018;Sharma et al., 2017);(7) prevention of aggregates and filament formation in Alzheimer's disease (AD)(Kang et al., 2016;Madhavadas & Subramanian, 2017;Malik et al., 2015;Momtaz et al., 2018); (8) gastritis and antigastric ulcer effects(Muhammad et al., 2015;Nir et al., 2000); (9) inhibition of osteoclastogenesis(Mendi et al., 2017;Tsuji-Naito, 2008);(10) anti-inflammatory (Fayaz et al., 2019; Ose et al., 2019; Schink et al., 2018); (11) wound healing and dressings (Ahmed et al., 2019; Ferro et al., 2019; Seyed Ahmadi et al., 2019), and more recently, promise for use in wound care practices (Ahmed et al., 2020); ...
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Article
Cinnamomum zeylanicum (“Ceylon cinnamon/true cinnamon”) is native to Sri Lanka. In addition to generating significant foreign income, over 350,000 families are involved in the cinnamon industry, demonstrating its long‐established role in the Sri Lankan society. The spice constitutes many bioactive compounds with antioxidant, antimicrobial, and insecticidal properties, in addition to therapeutic and preventive effects against many diseases and disorders. New uses of cinnamon continue to emerge, and in this review, we discuss the opportunities for crop and product improvement, which will likely impact positively on the lives and livelihood of the population in Sri Lanka. Cinnamomum zeylanicum Blume, known as Ceylon cinnamon, is native to Sri Lanka, whereas Cinnamomum cassia J. Presl (Cassia cinnamon) and other types of Cinnamomum spp. are grown in China and many other parts of Asia. Ceylon cinnamon is relatively expensive due to its chemical composition, high quality, proven health benefits, and ultra‐low levels of the toxic chemical compound, coumarin, which is reported in comparatively high concentrations in Cassia cinnamon. In Sri Lanka, more than 350,000 families are involved in the cinnamon industry. Among the total agricultural produce of Sri Lanka, cinnamon exports provide the second highest in terms of income (second only to tea). In addition to the use of cinnamon as a spice, leaf and bark extracts are used in the food industry to (a) improve the postharvest life of perishable foods through antimicrobial activity and (b) control pests in postharvest storage (insecticidal activity). The human health benefits include antioxidant activity and therapeutic and preventative properties against diseases and disorders. The potential uses of Ceylon cinnamon in the global food industry, health, and cosmetics sectors are abundant. However, to ensure maximum benefits to producers and consumers, accredited laboratory testing and legislative procedures need to be developed and strengthened to detect and reduce malpractice and product adulteration in the global marketplace. There are also considerable opportunities for crop improvement. The application of contemporary genomic and genetic approaches coupled to plant breeding will be needed to improve yields and disease resistance and to safeguard production in the face of the threats posed by global environmental change. Cinnamomum zeylanicum (“Ceylon cinnamon/true cinnamon”) is native to Sri Lanka. In addition to generating significant foreign income, over 350,000 families are involved in the cinnamon industry, demonstrating its long‐established role in the Sri Lankan society. The spice constitutes many bioactive compounds with antioxidant, antimicrobial, and insecticidal properties, in addition to therapeutic and preventive effects against many diseases and disorders. New uses of cinnamon continue to emerge, and in this review, we discuss the opportunities for crop and product improvement, which will likely impact positively on the lives and livelihood of the population in Sri Lanka.
... In addition to acarbose, multiple pharmaceuticals within the AGI class (miglitol and voglibose) remain unreported regarding their ability to enhance longevity, exhibit anti-cancer activity, and achieve CRM status using nondiabetic laboratory models. Additionally, natural AGIs of phytochemical/botanical origin (e.g., cinnamon, tea) are being increasingly identified and experimentally shown to alter and improve glycemic control [129][130][131][132][133][134]. In fact, multiple botanically derived AGIs show equivalence and/or superiority regarding in vitro pharmacokinetics to acarbose, and combination treatment with acarbose further enhances glycemic suppression [135,136]. ...
Article
The field of aging research has grown rapidly over the last half-century, with advancement of scientific technologies to interrogate mechanisms underlying the benefit of life-extending interventions like calorie restriction (CR). Coincident with this increase in knowledge has been the rise of obesity and type 2 diabetes (T2D), both associated with increased morbidity and mortality. Given the difficulty in practicing long-term CR, a search for compounds (CR mimetics) which could recapitulate the health and longevity benefits without requiring food intake reductions was proposed. Alpha-glucosidase inhibitors (AGIs) are compounds that function predominantly within the gastrointestinal tract to inhibit α-glucosidase and α-amylase enzymatic digestion of complex carbohydrates, delaying and decreasing monosaccharide uptake from the gut in the treatment of T2D. Acarbose, an AGI, has been shown in pre-clinical models to increase lifespan (greater longevity benefits in males), with decreased body weight gain independent of calorie intake reduction. The CR mimetic benefits of acarbose are further supported by clinical findings beyond T2D including the risk for other age-related diseases (e.g., cancer, cardiovascular). Open questions remain regarding the exclusivity of acarbose relative to other AGIs, potential off-target effects, and combination with other therapies for healthy aging and longevity extension. Given the promising results in pre-clinical models (even in the absence of T2D), a unique mechanism of action and multiple age-related reduced disease risks that have been reported with acarbose, support for clinical trials with acarbose focusing on aging-related outcomes and incorporating biological sex, age at treatment initiation, and T2D-dependence within the design is warranted.
... Poor insulin sensitivity is a pioneer to type 2 diabetes, affecting over 300 million people worldwide, and is often considered as elevated fasting blood glucose (FBG), of 5.5-6.9 mmol/L [6]. Cinnamon has vasodilative, anti-thrombotic, antispastic, anti-ulcerous, and anti-allergic action. ...
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Article
Cinnamon has a broad range of historical uses as a medicine and is often used as a flavoring agent in different cultures. Several studies have reported that cinnamon has vasodilative, anti-thrombotic, anti-spastic, anti-ulcerous and anti-allergic actions. Cinnamon has been shown to help lower blood glucose levels in people with diabetes. Objectives: To check the effect of cinnamon tea on diabetic patients and to evaluate how it lowers the glycemic index by using cinnamon in daily life cooking in diabetic men and women and also to access the knowledge of diabetes and eating habits of diabetic patients. Methods: This study examined the effect of cinnamon tea in both men and women (n-30). Blood samples were taken for 10 days to measure blood glucose levels. It was measured during fasting and after 6-hours of taking cinnamon tea. A self-made questionnaire was also developed to access the knowledge of diabetes and eating habits of diabetic patients. Results: There was a statistical decrease in blood glucose level after consumption of cinnamon tea. The mean decrease in the blood glucose level was 15.95. We also observed the standard deviations that the results in both conditions are similarly dispersed. T-value is significant as the p-value is less than 0.05. Only 10 (33.3%) patients had hypertension, 10 (33.3%) have blood pressure, 16 (53.3%) use insulin and 22 (73.3%) were physically inactive. Conclusion: This study will play an important role in the field of diabetes and its risk factors as cinnamon helps to improve blood glucose level in the diabetic patients and this will make people understand the value of cinnamon in diet.
... Cinnamon extracts (CE) have been reported to improve insulin sensitivity and glucose homeostasis by regulating hepatic enzymes activities, attributed to its phytochemical composition such as cinnamic acid, cinnamaldehyde and proanthocyanidins [125]. Supplementation of rat hepatoma cells (H4IIE) with (1-25 µg/mL) CE was demonstrated to inhibit hepatic glucose production by downregulating the expression of PEPCK and G6pase (Figure 2), concomitantly decreasing blood glucose levels [126]. ...
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Article
Type 2 diabetes mellitus (T2DM) is a complex metabolic disorder with various contributing factors including genetics, epigenetics, environment and lifestyle such as diet. The hallmarks of T2DM are insulin deficiency (also referred to as β-cell dysfunction) and insulin resistance. Robust evidence suggests that the major mechanism driving impaired β-cell function and insulin signalling is through the action of intracellular reactive oxygen species (ROS)-induced stress. Chronic high blood glucose (hyperglycaemia) and hyperlipidaemia appear to be the primary activators of these pathways. Reactive oxygen species can disrupt intracellular signalling pathways, thereby dysregulating the expression of genes associated with insulin secretion and signalling. Plant-based diets, containing phenolic compounds, have been shown to exhibit remedial benefits by ameliorating insulin secretion and insulin resistance. The literature also provides evidence that polyphenol-rich diets can modulate the expression of genes involved in insulin secretion, insulin signalling, and liver gluconeogenesis pathways. However, whether various polyphenols and phenolic compounds can target specific cellular signalling pathways involved in the pathogenesis of T2DM has not been elucidated. This review aims to evaluate the modulating effects of various polyphenols and phenolic compounds on genes involved in cellular signalling pathways (both in vitro and in vivo from human, animal and cell models) leading to the pathogenesis of T2DM.
... Our results are in concordance with a previous meta-analysis assessing cinnamon intake on HbA1c (Davis et al., 2011). The six cinnamon trials included by Davis et al. (2011) (n D 435 subjects) led to a significant decrease in mean HbA1c (0.09%; 95% CI: 0.04 to 0.14). ...
Article
Polyphenols have been extensively studied for their antioxidant and anti-inflammatory properties. Recently, their antiglycative actions by oxidative stress modulation have been linked to prevention of diabetes and associated complications. This paper assesses the evidence for polyphenol interventions on glycohaemoglobin (HbA1c) in non-diabetic, pre-diabetic and type 2 diabetes mellitus (T2DM) subjects. A systematic review of polyphenols clinical trials on HbA1c in humans was performed according to the Preferred Reporting Items for Systematic Review and Meta-Analysis. Thirty-six controlled randomized trials with HbA1c values were included. Polyphenols (extracts, supplements, foods), were supplemented (28 mg to 1.5g) for 0.7 to 12 months. Combining all subjects (n=1954, mean baseline HbA1c=7.03%, 53 mmol/mol), polyphenol supplementation significantly (p<0.001) lowered HbA1c% by -0.53±0.12 units (-5.79±0.13 mmol/mol). This reduction was significant (p<0.001) in T2DM subjects, specifically (n=1426, mean baseline HbA1c=7.44%, 58 mmol/mol), with HbA1c% lowered by -0.21±0.04 units (-2.29±0.4 mmol/mol). Polyphenol supplementation had no significant effect (p>0.21) in the non-diabetic (n=258, mean baseline HbA1c=5.47%, 36 mmol/mol) and the pre-diabetic subjects (n=270, mean baseline HbA1c=6.06%, 43 mmol/mol) strata: -0.39±0.27 HbA1c% units (-4.3±0.3 mmol/mol), and -0.38±0.31 units (-4.2±0.31 mmol/mol), respectively. In conclusion, polyphenols can successfully reduce HbA1c in T2DM, without any intervention at glycaemia, and could contribute to the prevention of diabetes complications.
... [8] For instance, several dietary supplements including resveratrol, cinnamon, ginger and cumin are proposed to be effective in blood glucose control. [9][10][11][12] A meta-analysis also showed that fasting glucose levels are reduced after supplementation with flavonols. [13] Flavonoids represent a very diverse group of biologically active compounds synthesized during plant metabolism. ...
Article
Aim: To the best of our knowledge, no study has tried to quantitatively summarize the published evidence regarding the effect of hesperidin supplementation on blood glucose control. The present systematic review and meta-analysis of randomized controlled trials aimed to determine the effectiveness of hesperidin supplementation in improving blood glucose control in adults. Materials and methods: Electronic databases including PubMed, ISI Web of Science, Scopus, and Google Scholar were searched up to February 2019. The risk of bias in individual studies was assessed using the Cochrane collaboration's tool. The overall estimates and their 95% confidence intervals (CIs) were calculated using a random-effects model. Results: Six trials with 318 participants were reviewed in the present systematic review. The results showed that hesperidin had no significant effect on serum fasting blood glucose (WMD = -1.10 mg/dL, 95% CI: -3.79, 1.57), plasma insulin (WMD = -0.01 μU/mL, 95% CI: -1.20, 1.19), glycated hemoglobin A1c (WMD = -0.04%, 95% CI: -0.14, 0.04), homeostasis model assessment for insulin resistance (HOMA-IR) (WMD = 0.117, 95% CI: -0.06, 0.29) and quantitative insulin sensitivity check index (QUICKI) (WMD = 0.135; 95% CI: -0.13, 0.39), with no significant between-study heterogeneity. Subgroup analyses also indicated that the effects were not different based on the studies' design andduration, or the health status of the participants. Conclusion: Although several animal studies have proposed that hesperidin supplementation might improve blood glucose control, the present study could not confirm this benefit in humans.
... In type II diabetic patients, resveratrol [182], berberine [183,184] and catechin [185] resulted in a decrease in insulin resistant and an increase in insulin level. A meta-analysis of clinical studies in diabetic patients showed that cinnamon or cinnamon extracts decrease fasting blood glucose levels [186]. As high blood glucose level leads to the activation of AR enzyme of the polyol pathway in DNP [21], so resveratrol, catechin and cinnamon could be effective compounds to combat DNP. ...
Article
Objectives: Diabetic neuropathy (DNP) is a widespread and debilitating complication with complex pathophysiology that is caused by neuronal dysfunction in diabetic patients. Conventional therapeutics for DNP are quite challenging due to their serious adverse effects. Hence, there is a need to investigate novel effective and safe options. The novelty of the present study was to provide available therapeutic approaches, emerging molecular mechanisms, signaling pathways and future directions of DNP as well as polyphenols' effect, which accordingly, give new insights for paving the way for novel treatments in DNP. Evidence acquisition: A comprehensive review was done in electronic databases including Medline, PubMed, Web of Science, Scopus, national database (Irandoc and SID), and related articles regarding metabolic pathways on the pathogenesis of DNP as well as the polyphenols' effect. The keywords "diabetic neuropathy" and "diabetes mellitus" in the title/abstract and "polyphenol" in the whole text were used. Data were collected from inception until May 2019. Results: DNP complications is mostly related to a poor glycemic control and metabolic imbalances mainly inflammation and oxidative stress. Several signaling and molecular pathways play key roles in the pathogenesis and progression of DNP. Among natural entities, polyphenols are suggested as multi-target alternatives affecting most of these pathogenesis mechanisms in DNP. Conclusion: The findings revealed novel pathogenicity signaling pathways of DNP and affirmed the auspicious role of polyphenols to tackle these destructive pathways in order to prevent, manage, and treat various diseases. Graphical Abstract .
... 34 While early meta-analyses have generally concluded that there is insufficient evidence to support the use of cinnamon for treatment of type 1 or type 2 diabetes, 35 other systematic reviews support a beneficial effect on fasting plasma glucose and HbA 1c in short-term usage of <4 months in subjects with metabolic syndrome or prediabetes. 34,[36][37][38][39] The dramatic increase in fiber content between PROG2 and PROG1 could also function to improve glycemic control. In a 4-week randomized control study of 10 or 20 g soluble fiber per day versus 0 g per day in type 2 diabetics, Chen et al. 40 reported that the 20 g/day soluble dietary fiber group exhibited significantly improved fasting blood glucose and low-density lipoprotein levels, as well as insulin resistance index, waist and hip circumferences, TG, and apolipoprotein A. In addition, both cross-sectional 41 and prospective 42 studies support the concept that soluble dietary fiber can be an effective addition to a lifestyle intervention program for prediabetes or CMS. ...
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Among the comorbidities of high body mass index, cardiovascular disease continued to be the leading cause of death and disability globally in 2015, while type 2 diabetes remained second. The primary objectives of this observational study were to confirm the safety, tolerability, and efficacy of our calorie-restricted Mediterranean diet with targeted dietary supplementation (PROG1) using globally recognized dietary supplementation. Fifty healthy overweight and obese subjects with cardiometabolic risk factors were assigned a modified Mediterranean diet, including protein shakes and targeted supplementation (PROG2), providing ∼68-76% of subject estimated calorie requirements. Salivary nitrite was assessed weekly and key cardiometabolic metrics were recorded at baseline and weeks 9 and 13. PROG2 was well tolerated with 86% compliance. The most common adverse effects were bloating, flatulence, and constipation, which were self-limiting. Subjects exhibited decreases (P < .01) from baseline of 12% in body weight, 18% in body fat, and 8.8% in waist circumference. Total cholesterol (TC), low-density lipoprotein (LDL) cholesterol, and triglycerides (TG) were reduced (P < .01), respectively, 19%, 22%, and 40%. Lipid ratios of TC/high-density lipoprotein (HDL), TG/HDL, and oxidized LDL (oxLDL)/HDL were decreased 15% (P < .01), 35% (P < .01), and 13% (P < .05), respectively. Inflammation biomarkers, oxLDL and high-sensitivity C-reactive protein, were reduced 17% (P < .01) and 30% (P < .05), respectively. Reductions of 9.0% for systolic (P < .01) and 12% (P < .01) for diastolic blood pressure were noted. In concert, the nitrogen dioxide salivary biomarker for nitric oxide was increased relative to baseline. PROG2 produced a dramatic 50% reduction in subjects meeting cardiometabolic syndrome criteria and a 38% decrease in Framingham 10-year cardiovascular risk. These results confirmed our previous findings that the addition of targeted nutraceutical supplementation to a calorie-restricted Mediterranean diet with lifestyle modifications improves multiple longevity risk factors more effectively than diet and lifestyle modification alone.
... Accordingly, it has been suggested that at least 1-2 grams of ground or extract Chinese cinnamon should be used 1-2 months in order to see a minimal impact. Again, based on research results, it has been shown that although it causes no effect on blood glucose of people with normal blood glucose levels, it is effective on blood glucose in people with type 2 diabetes and prediabetes [23]. ...
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Background: This study was aimed at investigating the effect of consumption of different amounts of cinnamon on preprandial blood glucose (PrBG), postprandial blood glucose (PoBG), glycosylated hemoglobin (HbA1c), and body mass index (BMI). Methods: This study was carried out on 41 healthy adult individuals. The individuals were divided into 3 groups and monitored for 40 days. The first, second, and third groups were given 1 g/day, 3 g/day, and 6 g/day cinnamon, respectively. Before the beginning of the consumption of cinnamon, HbA1c and PrBG blood tests of the individuals were examined on an empty stomach at family practice centers. Two hours after these tests were carried out and breakfast, PoBG tests were performed. Results: According to the findings of the study, the differences between the average weight measurements, BMI values, and HbA1c values before consumption on days 20 and 40 were not statistically significant in the individuals consuming 1 g, 3 g, and 6 g of cinnamon a day. The difference between the average PrBG measurements was found to be significant in the individuals consuming 6 g of cinnamon per day. The difference between the average PoBG measurements before consumption on days 20 and 40 was significant in the individuals consuming 1 g, 3 g, and 6 g of cinnamon per day. Conclusions: In particular a 3-6 g of cinnamon consumption was found to affect certain blood parameters of individuals positively. Therefore, it is considered to be beneficial to raise awareness of individuals to be conscious to regularly consume cinnamon.
... [7][8][9][10] Cinnamomum (cinnamon) that is a genus from the Lauraceae family is an example of such herbs. 11,12 Cinnamon means sweet wood and is obtained from the inner bark of cinnamon treesas a spice or traditional remedy for several diseases including common cold, gastrointestinal disorder and diabetes. 13 It posses several species including C.cassia, C.burmannii, C.verum, C.loureiroi, C.citriodorum, and C.tamale. ...
... The prevalence of hypoglycemia in patients with Type 2 diabetes is 30%-35% (Edridge et al. 2015). Beneficial effects on fasting blood sugar have been shown for main ingredients in this supplement category, including cinnamon bark extract (Davis and Yokoyama 2011;Lu et al. 2012), chromium complexes (Abdollahi et al. 2013), berberine (Zhang et al. 2010), and alpha-lipoic acid (Kamenova 2006;Papanas and Ziegler 2014). There was a single case of documented hypoglycemia in a customer taking this product, which would be consistent with the intended mechanism of action of the supplements. ...
Article
Dietary supplement marketers assure the safety of their products by complying with current good manufacturing practices and a host of federal regulations, including those enforced by the Food and Drug Administration (FDA). Post-market surveillance is a key part of identifying safety problems associated with dietary supplement products. FDA requires dietary supplement marketers to provide a domestic address or phone number on product labels for consumers, family members, or health care professionals to report adverse events (AEs) associated with product use and to report all serious adverse events (SAEs) to the agency within 15 business days of receipt. We aimed to evaluate the characteristics of AEs reported with dietary supplement use, including dietary supplement type and Medical Dictionary for Regulatory Activities (MedDRA) system organ class (SOC) that occur with reported SAEs. A total of 41,121 unique adverse event cases reported to two large, U.S.-based dietary supplement marketers in a 2.5-year period (March 1, 2014–August 31, 2016) were assessed for seriousness using established criteria. Each SAE was assigned one or more MedDRA preferred terms and system organ classes (SOC). The types of supplements most responsible for SAEs were assessed. Of the 41,121 AE cases reported, 203 (0.48%) were SAEs. SAEs tended to occur with products marketed for weight loss (69.0%) and glycemic control (19.2%). SAEs occurred most commonly in the cardiovascular, gastrointestinal, and nervous system disorder SOCs. The percentage of SAEs reported to dietary supplement marketers is low, predominantly among consumers of two types of supplements. Further study is needed among a larger cohort of supplement users to determine causal associations between types of supplement products and serious adverse events.
... Both glycine and cinnamon have been reported to have a favourable impact on blood glucose, which may be beneficial in improving metabolic health, in particular for those with slightly elevated fasting blood glucose (100-125 mg•dL -1 ) and considered to be pre-diabetic [1,2]. It is estimated that approximately 84 million adults living within the United States have pre-diabetes, many of whom can benefit from nutritional approaches aimed at reducing fasting and post-prandial blood glucose [3]. ...
Article
Objective: slightly elevated have been independently reported to favorably impact blood glucose. To our knowledge, no study has combined these two ingredients through oral supplementation in an attempt to modify the glycemic response to a glucose load. We determined the impact of acute ingestion of a novel glycine-cinnamon extract mixture on blood glucose, insulin, and related variables following an oral glucose challenge.Methods: Ten men and women (25.4 ± 8.3 yrs) with elevated fasting blood glucose (101.2 ± 6.6 mg•dL-1) ingested a 25 gram glucose beverage with and without SugarClear™, a proprietary blend of glycine+cinnamon extract (as Cinnulin PF®), separated by approximately one week. Blood was collected before and at 20, 60, and 120 minutes post ingestion and analyzed for glucose, insulin, glucagon-like peptide-1 (GLP-1), glucagon, ATP, and brainderived neurotrophic factor (BDNF).Results: Significant reductions in the area under the curve (AUC) were noted for both glucose (15% for total AUC and 52% for net incremental AUC) and insulin (7% for total AUC and 57% for net incremental AUC). The total AUC for GLP-1 was increased by 36%, while the AUC for ATP was increased by 20%. Glucagon was lower by 10% and BDNF higher by 5% with treatment but not in a statistically significant manner (p>0.05).Conclusion: Acute ingestion of SugarClear™, a proprietary blend of glycine and cinnamon extract, promotes a positive impact on blood glucose and insulin following an oral glucose load. The mixture also leads to an increase in both the plasma GLP-1 and ATP. These alterations may have favourable metabolic implications in those with elevated blood glucose. Future work is needed to determine the effect of chronic ingestion of SugarClear™ on glucose regulation and related variables.
... Several studies have shown that cinnamon has many functional properties, such as antibacterial, antifungal, and antioxidant properties, and recent publications also suggested health benefits with the inclusion of cinnamon in the diet [3][4][5]. In spite of some controversial clinical trials results [6][7][8][9], recent studies proposed that cinnamon ingestion in doses varying from 0.12 to 6 g day −1 , for 1 day to 4 months, can reduce fasting plasma glucose levels [10][11][12] and improve lipid profile in healthy and type 2 diabetes mellitus (DM) subjects [13,14]. ...
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Recent studies highlighted the beneficial action of cinnamon on postprandial glycemia and LDL-cholesterol concentrations, both in healthy subjects and type 2 diabetic patients. Inclusion of 3 to 6 g of cinnamon in diet revealed a beneficial effect on glucose metabolism control in non-diabetic adults during postprandial period. Given the levels of toxic elements present in cinnamon species from different countries, such large daily intakes of cinnamon can easily exceed their maximum permissible limits and, consequently, induce adverse health effects. This study aimed to investigate the elemental concentration profile in cinnamon powder products available in the Portuguese market and to assess the cumulative non-carcinogenic risk to human health due to the exposure to mixtures of such elements through the inclusion of 6 g of cinnamon in diet. Concentrations of Cu, Zn, Fe, Al, Cl, Mn, and Sr were determined by wavelength dispersive X-ray fluorescence spectroscopy in different lots of eight branded and one bulk cinnamon powder products. Linear mixed models have revealed significant differences in concentrations of Zn, Fe, Al, and Cl between brands. In particular, bulk cinnamon samples presented the highest contents of Fe (475.0–490.0 mg kg−1) and Al (1139.0–1336.0 mg kg−1). The non-carcinogenic risk was assessed following EPA’s guidelines through the hazard quotient (HQ). Estimated HQ values were lower than the USEPA guideline of 1. Additionally, the hazard index (HI), representing the combined non-carcinogenic effects of all toxic elements, revealed no potential human health risk for heavy consumers of cinnamon (HI = 0.660). ᅟ
... Cinnamon has been the subject of numerous studies to determine its effect on blood glucose levels. It has been suggested that the mode of action in which cinnamon expresses its effect on blood glucose can be attributed to its active component cinnamaldehyde [37]. A study carried out by Davis et al. (2011) has shown that cinnamon, in whole form or extract, helps lower fasting blood glucose levels [38]. ...
... with Type 2 diabetes through improving the ability to respond to insulin. A total of 8 meta-analysis clinical studies demonstrated that cinnamon or cinnamon extracts decrease fasting blood glucose levels (51). Cinnamon slows the rate of stomach emptying after eating. ...
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Background: Type 2 diabetes is a growing public health problem and is associated with increased morbidity and mortality. The worldwide prevalence of type 2 diabetes is rising. Polyphenols, such as flavonoids, phenolic acid, and stilbens, are a large and heterogeneous group of phytochemicals in plant-based foods. In this review, we aimed at assessing the studies on polyphenols and diabetes management. Methods: A literature search in the PubMed, EMBASE, Scopus, and ISI Web of Science databases was conducted to identify relevant studies published from 1986 to Jan 2017. Results: Several animal models and a limited number of human studies have revealed that polyphenols decrease hyperglycemia and improve acute insulin secretion and insulin sensitivity. The possible mechanisms include decrease in glucose absorption in the intestine, inhibition of carbohydrates digestion, stimulation of insulin secretion, modulation of glucose release from the liver, activation of insulin receptors and glucose uptake in insulin-sensitive tissues, modulation of intracellular signaling pathways, and gene expression. Conclusion: Growing evidence indicates that various dietary polyphenols may influence blood glucose at different levels and may also help control and prevent diabetes complication. However, we still need more clinical trials to determine the effects of polyphenols- rich foods, their effective dose, and mechanisms of their effects in managing diabetes.
... Some recent meta-analyses failed to reach a conclusive result on the potential benefit of cinnamon in patients with diabetes [15,24,25], due to the heterogeneity of the results of the included studies [15]. Different responses to hypoglycemic agents by obese and lean diabetic patients have been well documented previously [26,27]. ...
Article
Background & aims Multiple studies have evaluated the hypoglycemic effect of cinnamon in patients with diabetes mellitus (DM) type II, with conflicting results. Differences in Baseline Body Mass Index (BMI) of patients may be able to explain the observed differences in the results. This study was designed to evaluate the effect of cinnamon supplementation on anthropometric, glycemic and lipid outcomes of patients with DM type II based on their baseline BMI. Methods The study was designed as a triple-blind placebo-controlled randomized clinical trial, using a parallel design. One hundred and forty patients referred to Diabetes Clinic of Yazd University of Medical Sciences with diagnosis of DM type II were randomly assigned in four groups: cinnamon (BMI ≥ 27, BMI < 27) and Placebo (BMI ≥ 27, BMI < 27). Patients received cinnamon bark powder or placebo in 500 mg capsules twice daily for 3 months. Anthropometric, glycemic and lipid outcomes were measured before and after the intervention. Result Cinnamon supplementation led to improvement of all anthropometric (BMI, body fat, and visceral fat), glycemic (FPG, 2hpp, HbA1C, Fasting Insulin, and Insulin Resistance), and lipids (Cholesterol Total, LDL-c and HDL-c) outcomes (except for triglycerides level). All observed changes (except for Cholesterol Total and LDL-c) were significantly more prominent in patients with higher baseline BMI (BMI ≥ 27). Conclusion Based on the study findings, cinnamon may improve anthropometric parameters, glycemic indices and lipid profile of patients with type II diabetes. These benefits are significantly more prominent in patients with higher baseline BMI (BMI ≥ 27). The trial protocol was registered in Iranian Registry of Clinical Trials database (registration ID: IRCT2017031133015N1).
... Allen et al. [25] showed effective role of cinnamon on fasting blood glucose, total cholesterol, triglycerides and LDL in a systemic review and meta-analysis. Cinnamon exhibits plasma glucose lowering effects reported by Pham et al. [26] and Davis et al. [27] in their meta-analysis. To the contrary, Blevins et al. [28] stated that cinnamon has no effect on plasma glucose and lipid levels in type 2 diabetic subjects in US population. ...
... 23 Cinnamon might be helpful for lowering the fasting blood glucose and serum glycosylated hemoglobin (HbA1C) in type 2 diabetes with HbA1C greater than 7.0 in additions to usual care. 24 Davis and Yokoyama 25 found that cinnamon intake significantly lowering the fasting blood glucose. Hoehn and Stockert 26 observed a greater decrease in blood glucose values in patients under a 12-week trial using the cinnamon when compared to those using the dietary changes alone. ...
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Cinnamomum zeylanicum Linn. has been used as a spice and flavoring agents. It is one of the healthiest spices and possesses useful medicinal benefits. It has been recognized as the medicinally essential phytocon­ stituents, such as phenolic, flavonoid and carotenoid. It is loaded with rich amount of polyphenols, which are the powerful antioxidants. It inhibits the growth of certain bacteria and fungi. It dramatically reduce insulin resistance, there by helps insulin to reduce blood glucose. It also slow down the break down of carbohydrate by interfering with carbohydrate digesting enzymes and decreases the entry of glucose from intestine to bloodstream. It reduces the growth of cancer cells. Numerous pharmacological investigations have confirmed that the ability of this plant is to exhibit hepatoprotective, cardio­ protective, and neuroprotective activities and it supports the traditional uses. Present review gives a detailed information on recent literatures describing the multipotential uses of C. zeylanicum available for the treating various ailments.
Chapter
Antioxidants are substances that fight free radicals produced in the body due to several intrinsic as well as extrinsic factors such as pollution, smoking, UV radiation, etc. They play a preventive as well as scavenging role in removing the excess free radicals thereby preventing oxidative stress. Oxidative stress is capable of disturbing the normal body physiology and may cause lethal diseases such as cancer, Alzheimer’s, diabetes, etc. The antioxidants have an important role to play with the rapid increase in the external forces causing uncontrolled generation of free radicals. The human body produces its own antioxidants, called endogenous antioxidants. However, some antioxidants are obtained from external sources; these exogenous antioxidants fulfill the dietary requirements of the body. In the present chapter, natural as well as synthetic antioxidants have been discussed with special emphasis on plant-derived antioxidants and their potential applications in the treatment and management of life-threatening diseases. Plants being an all-natural hub for antioxidants have been discussed for their safer use, variety, and dosage. In addition to this, the role of antioxidants in the food, packaging, and cosmetics industry has also been highlighted. This chapter sums up the potential applications as well as working of antioxidants while underscoring its future prospects for further study.
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Cinnamon is obtained from a plant whose products have been used daily by people all over the world. Cinnamon is a popular culinary spice, and the oil of cinnamon is used in medicine as a carminative, antiseptic, and astringent. Cinnamon has recently become increasingly popular for its benefits in glycemic control. It has been used for the treatment of coronary risk factors, particularly hypertension, diabetes mellitus, and obesity, and for ameliorating dyslipidemia. Its leaf and bark have digestive, blood purifier, astringent, carminative, warming stimulant, antiseptic, antibacterial, antifungal, and antiviral properties and can help to reduce cholesterol and blood sugar levels. Several mechanisms have been described for the action of polyphenols isolated from cinnamon. These compounds seem to modulate multiple steps of the insulin signal transduction pathway, stimulating the glucose uptake and glycogen synthesis. These bioactive compounds of cinnamon have also been shown to have insulin-independent effects on the regulation of gene expression in adipocytes. In brief, this review indicates that cinnamon has potential beneficial effects on blood glucose, body weight, blood lipids, and blood pressures.
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Cinnamon Botany, Agronomy, Chemistry and Industrial Applications
Chapter
Spices have been added to foods for centuries as flavors, preservatives, and colors and have also been used in traditional medicine in various countries to treat many diseases. Spices play an important role in human health and can be considered as the first functional foods. Although the amount of spices consumed is very low compared to many other foods, the role of spices in the daily diet should not be underestimated due to their health properties. Saffron, ginger, cinnamon, and turmeric are four globally common spices that have been widely used owing to well-known medical benefits in different traditional medicine systems, including Ayurveda, traditional Chinese, and Persian medicine since ancient times. Some general or specific health benefits of these spices include anti-inflammatory, antioxidantAntioxidant, antimicrobial, anti-diabetic, and antihypertensive activities, which have potential protective properties against some ailments such as cancer, type 2 diabetesDiabetes, neurodegenerative and cardiovascular diseases. Recent scientific studies on the therapeutic properties of these common spices have been reviewed in this chapter.
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Ceylon cinnamon, which is also known as true cinnamon, has been very popular as a spice and a traditional medicine for centuries. Cinnamon growing in Sri Lanka was sought after by many countries. Presently, Cinnamomum zeylanicum is considered a superior quality material and fetches a high price. Research undertaken on the health benefits of cinnamon are conducted using the bark, bark powder, extracts and bark and leaf essential oils. Many antioxidants, flavonoids and phenolic compounds have been isolated. Value addition of this material can be undertaken to convert it to additional products, such as health supplements and herbal healthcare products, which are gaining popularity at the present time. The applications using cinnamon are being subjected to scientific research in order to be used for medicinal purposes. Results so far obtained using in vitro and animal in vivo models indicate that cinnamon has antimicrobial, antioxidant, anti-inflammatory, cardiovascular, cholesterol-lowering, antidiabetic and immunomodulatory effects. Yet, only very few controlled clinical studies have been done to confirm these potential health benefits. The promising applications of cinnamon as a flavour in aromatherapy and in nutraceutical and cosmeceutical industries are outlined with future market prospects.
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Sri Lanka is the market leader of Ceylon cinnamon with a 90% global market share. Cinnamon is one of the leading foreign exchange earners from among agricultural exports of Sri Lanka. The cinnamon extent of cultivation, production, and yield has only marginally increased over the past few decades despite high potential in the global market. However, the major competitive product cassia produced and exported predominantly by Indonesia, China, and Vietnam has contributed to the erosion of Ceylon cinnamon market share, notwithstanding warning from leading health agencies about its negative impact on health due to high content of coumarin. Ceylon cinnamon has the potential to become Sri Lanka’s number one foreign exchange earner from the agriculture sector by building on its competitive edge as the main true cinnamon supplier. Product and process innovation with a focus on compliance with food safety and quality requirements remains the most feasible and practical option to exploit the competitive edge of Ceylon cinnamon in the global marketplace. Marketing strategies should focus on product diversification, value addition, and brand recognition.
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Mounting evidence suggests a link between metabolic syndrome in the progression of neurodegenerative diseases, where mitochondrial defects and altered balance of reactive oxygen species play a crucial role in such disease progression. Though there have been many clinical trials exploring the efficacy of using cinnamon and its metabolites in the treatment of metabolic syndrome and neurodegenerative diseases, their results are mostly inconclusive; thus, it is important to effectively design clinical trials where the effect would be monitored with validated biomarker- and clinical marker-based surrogate end points. Even though clinical trials with cinnamon as a therapy has been carried out, very few clinical trials or animal studies have been performed with Cinnamomum zeylanicum. This chapter provides a comparative analysis of cinnamon clinical trials in healthy people versus patients with metabolic syndrome and neurological disorders in order to determine the effect of cinnamon on metabolic syndrome and neurological diseases.
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Introduction: 'Prediabetes' is a condition of elevated glucose not attaining the established criteria for a diagnosis of diabetes. The United States Diabetes Prevention Program (DPP) began in 1996 and was the iconic study of prediabetes. In that study, after 3 years, the risk of reaching the numerical criteria of diabetes was reduced by 58% by intensive emphasis on diet and exercise whereas treatment with metformin achieved a lesser reduction of 31%. The DPP was widely heralded as suggesting that lifestyle change was superior to pharmacologic therapy in the prediabetes population. This conclusion may be overreaching in terms of the long-term results of that study. Areas covered: The author reviews the subsequent pharmacologic efforts to prevent diabetes in this population. He reviews the existing literature for pharmacologic treatment of prediabetes using Pubmed.gov using the keywords of prediabetes, impaired fasting glucose and impaired glucose tolerance. Expert opinion: Prediabetes is primarily related to being overweight. Obesity has health consequences going beyond glucose elevation. The approach to prediabetes should be primarily by pursuing weight loss with therapeutic agents such as GLP-1 receptor agonists and SGLT2 inhibitors.
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Cinnamon has become a natural product of interest because it has been hypothesized to provide health benefits, such as the ability to lower serum lipids and blood glucose. There have been randomized controlled trials (RCTs) for its glycemic-lowering effects, but studies have been shown small conflicting results. We performed an updated meta-analysis of RCTs evaluating cinnamon's effect on glycemia and lipid levels. Methods: Clinical trials were identified through MEDLINE, Cochrane, the Google scholar, MeSH, Medscape, www. Clinicaltrial.gov from 1990 to March 2015 were searched Included RCTs evaluated cinnamon compared with control in patients with type 2 diabetes and reported at least one of the following: glycated hemoglobin (A1c), fasting plasma glucose, total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), or triglycerides. Weighted mean differences (with 95% confidence intervals) for endpoints were calculated using random-effects models. Results: In a meta-analysis of 16 RCTs (n = 638 patients), cinnamon doses of 120 mg/d to 6 g/d for 4 to 18 weeks reduced levels of fasting plasma glucose,16 RCTs (n = 638 patients) (-0.38 gm/dL; 95% CI,-0.54 to-0.21 gm/dL), total cholesterol, 15 RCT (n=567), (-12.87 mg/ dL; 95% CI,-15.53 to-10.22 mg/dL), Cinnamon also increased levels of HDL-C, 10 RCTs (n=461 patients) (-0.14 mg/dL; 95% CI,-0.13-0.15 mg/dL), and LDL-C, 15 RCTs (n=521 patients) (-9.07 mg/dL; 95% CI,-11.05 to-7.09 mg/dL), triglycerides, RCTs 15 (n=544 patients), (-13.25 mg/dL; 95% CI,-16.21 to-10.29 mg/dL). No significant effect on hemoglobin A1c levels, 11 RCTs (n=627), (0.07%; 95%, CI-0.03% to 0.16 %) was seen. High degrees of heterogeneity were present for all analyses. W WO OR RL LD D J JO OU UR RN NA AL L O OF F P PH HA AR RM MA AC CY Y A AN ND D P PH HA AR RM MA AC CE EU UT TI IC CA AL L S SC CI IE EN NC CE ES S S SJ JI IF F I Im mp pa ac ct t F Fa ac ct to or r 5 5. .2 21 10 0 V Vo ol lu um me e 4 4, , I Is ss su ue e 0 05 5, , 1 18 83 38 8-1 18 85 52 2.. R Re es se ea ar rc ch h A Ar rt ti ic cl le e I
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Spices have broadly been used as food flavoring and folk medicine since ancient times. Numerous phytochemicals have been identified in spices, namely thymol (ajowan and thyme), anethole (aniseed), piperine (black pepper), capsaicin (capsicum), cinnamaldehyde (cinnamon), eugenol (clove), linalool (coriander), sabinene (curry leaf), limonene (dill seed), estragole (fennel seed), allicin (garlic), gingerol (ginger), safranal (saffron), and curcumin (turmeric), among others. The antioxidants in spices are very effective and also render anti-mutagenic, cardioprotective, anti-inflammatory, and anti-cancer properties. Apart from their antioxidant efficacy, spices, particularly their essential oils possess strong antimicrobial activity against bacteria, fungi, yeasts, and microbial toxins synthesis. In this contribution, a summary of the most relevant and recent findings on phytochemical composition and antioxidant properties of spices has been compiled and discussed. The content of phenolic acids, flavonoids, tannins, glycosides, steroids, and terpenoids in different spices are summarized. In addition, the beneficial effects of spices in food preservation and in health promotion and disease risk reduction are briefly described.
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Spices have broadly been used as food flavoring and folk medicine since ancient times. Numerous phytochemicals have been identified in spices, namely thymol (ajowan and thyme), anethole (aniseed), piperine (black pepper), capsaicin (capsicum), cinnamaldehyde (cinnamon), eugenol (clove), linalool (coriander), sabinene (curry leaf), limonene (dill seed), estragole (fennel seed), allicin (garlic), gingerol (ginger), safranal (saffron), and curcumin (turmeric), among others. The antioxidants in spices are very effective and also render anti-mutagenic, cardioprotective, anti-inflammatory, and anti-cancer properties. Apart from their antioxidant efficacy, spices, particularly their essential oils possess strong antimicrobial activity against bacteria, fungi, yeasts, and microbial toxins synthesis. In this contribution, a summary of the most relevant and recent findings on phytochemical composition and antioxidant properties of spices has been compiled and discussed. The content of phenolic acids, flavonoids, tannins, glycosides, steroids, and terpenoids in different spices are summarized. In addition, the beneficial effects of spices in food preservation and in health promotion and disease risk reduction are briefly described.
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Purpose: This meta-analysis aimed to evaluate the effect of cassia cinnamon (Cinnamomum. cassia and C. aromaticum) on the glycemic response with a focus on the preparation of dehydrated powder and water extract. Methods: We searched Pubmed, Cochrane, EMBASE, Science Direct, and the Korean Studies Information Service System (KISS) through May 2017. In the meta-analysis for the preparation of powder, eight trials reporting fasting blood glucose (FBG), four trials reporting HbA1c, and three trials reporting the postprandial glycemic response were included. For the water extract, six trials reporting FBG and four trials reporting HbA1c were eligible for this study. A random-effects model was used to calculate the pooled effect size. Results: Cassia cinnamon powder intake significantly lowered FBG by -1.55 mmol/L (95% CI, -2.45, - 0.64; p = 0.001) and the AUC of postprandial blood glucose level by -51.8 mmol/L·min (95% CI, -85.5, -18.1; p = 0.003). There was a significant difference in FBG between water extract of cinnamon and placebo of -0.76 mmol/L (95% CI, -1.09, -0.43; p = 0.000). However, blood HbA1c level was not significantly altered by any preparation of cinnamon. No statistical heterogeneity was observed for any analysis except in the case of FBG for cinnamon powder. Results of funnel plots and Egger's regression suggest a low likelihood of publication bias in all biomarkers (p > 0.05). Conclusion: According to this meta-analysis, there was possible evidence to support a relationship between cassia cinnamon intake and fasting glucose in both preparation of powder and water extract. Furthermore, new evidence of the health benefits on postprandial glucose regulation of cinnamon powder was obtained.
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Antioxidants are substances that prevent oxidation of other compounds or neutralize free radicals. Spices and herbs are rich sources of antioxidants. They have been used in food and beverages to enhance flavor, aroma and color. Due to their excellent antioxidant activity, spices and herbs have also been used to treat some diseases. In this review article, the chemical composition and antioxidant activity of spices and culinary herbs are presented. The content of flavonoids and total polyphenols in different spices and herbs are summarized. The applications of spices and their impacts on human health are briefly described. The extraction and analytical methods for determination of antioxidant capacity are concisely reviewed.
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During fasting, mammals maintain normal glucose homeostasis by stimulating hepatic gluconeogenesis. Elevations in circulating glucagon and epinephrine, two hormones that activate hepatic gluconeogenesis, trigger the cAMP-mediated phosphorylation of cAMP response element-binding protein (Creb) and dephosphorylation of the Creb-regulated transcription coactivator-2 (Crtc2)--two key transcriptional regulators of this process. Although the underlying mechanism is unclear, hepatic gluconeogenesis is also regulated by the circadian clock, which coordinates glucose metabolism with changes in the external environment. Circadian control of gene expression is achieved by two transcriptional activators, Clock and Bmal1, which stimulate cryptochrome (Cry1 and Cry2) and Period (Per1, Per2 and Per3) repressors that feed back on Clock-Bmal1 activity. Here we show that Creb activity during fasting is modulated by Cry1 and Cry2, which are rhythmically expressed in the liver. Cry1 expression was elevated during the night-day transition, when it reduced fasting gluconeogenic gene expression by blocking glucagon-mediated increases in intracellular cAMP concentrations and in the protein kinase A-mediated phosphorylation of Creb. In biochemical reconstitution studies, we found that Cry1 inhibited accumulation of cAMP in response to G protein-coupled receptor (GPCR) activation but not to forskolin, a direct activator of adenyl cyclase. Cry proteins seemed to modulate GPCR activity directly through interaction with G(s)α. As hepatic overexpression of Cry1 lowered blood glucose concentrations and improved insulin sensitivity in insulin-resistant db/db mice, our results suggest that compounds that enhance cryptochrome activity may provide therapeutic benefit to individuals with type 2 diabetes.
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The prevalence of type 2 diabetes has increased in recent decades to epidemic proportions. About 150 million individuals worldwide had type 2 diabetes in 2000, and this number is expected to increase to ∼300 million by the year 2025 (1). Because of the chronic course of type 2 diabetes and the significant morbidity and mortality associated with the vascular complications of the disease, type 2 diabetes has become not only a serious public health threat, but also a heavy economic burden on the health care system. The total annual cost of diabetes care in the U.S. was estimated to be $175 billion in the year 2007, and this number is expected to increase further with the increasing incidence of the disease (2). Recent clinical trials have reported a reduction in the incidence of type 2 diabetes with lifestyle intervention (3,4) and pharmacotherapy (4,5) in subjects with IGT. These results suggest that primary prevention of type 2 diabetes could be an effective strategy to restrain the epidemic increase in the disease prevalence and reduce the economic burden it poses on the health care system. Accurate identification of subjects at increased risk for future type 2 diabetes is essential for an early prevention program. It minimizes the number of subjects in the intervention program while improving the efficacy and the cost-effectiveness of the intervention. An impaired glucose tolerance (IGT) test was introduced in 1979 as an intermediate state in the transition in glucose homeostasis from normal to overt diabetes (6). Subjects with IGT have increased risk for future type 2 diabetes (7). Thus, all previous intervention trials that have tested the efficacy of prevention strategies have recruited subjects with IGT (3–5). Although, in general, subjects with IGT have an increased risk for future type 2 …
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A previous study of healthy subjects showed that intake of 6 g cinnamon with rice pudding reduced postprandial blood glucose and the gastric emptying rate (GER) without affecting satiety. The objective was to study the effect of 1 and 3 g cinnamon on GER, postprandial blood glucose, plasma concentrations of insulin and incretin hormones [glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide 1 (GLP-1)], the ghrelin response, and satiety in healthy subjects. GER was measured by using real-time ultrasonography after ingestion of rice pudding with and without 1 or 3 g cinnamon. Fifteen healthy subjects were assessed in a crossover trial. The addition of 1 or 3 g cinnamon had no significant effect on GER, satiety, glucose, GIP, or the ghrelin response. The insulin response at 60 min and the area under the curve (AUC) at 120 min were significantly lower after ingestion of rice pudding with 3 g cinnamon (P = 0.05 and P = 0.036, respectively, after Bonferroni correction). The change in GLP-1 response (DeltaAUC) and the change in the maximum concentration (DeltaC(max)) were both significantly higher after ingestion of rice pudding with 3 g cinnamon (P = 0.0082 and P = 0.0138, respectively, after Bonferroni correction). Ingestion of 3 g cinnamon reduced postprandial serum insulin and increased GLP-1 concentrations without significantly affecting blood glucose, GIP, the ghrelin concentration, satiety, or GER in healthy subjects. The results indicate a relation between the amount of cinnamon consumed and the decrease in insulin concentration.
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The objective of this study was to determine whether cinnamon improves blood glucose, triglyceride, total cholesterol, HDL cholesterol, and LDL cholesterol levels in people with type 2 diabetes. A total of 60 people with type 2 diabetes, 30 men and 30 women aged 52.2 +/- 6.32 years, were divided randomly into six groups. Groups 1, 2, and 3 consumed 1, 3, or 6 g of cinnamon daily, respectively, and groups 4, 5, and 6 were given placebo capsules corresponding to the number of capsules consumed for the three levels of cinnamon. The cinnamon was consumed for 40 days followed by a 20-day washout period. After 40 days, all three levels of cinnamon reduced the mean fasting serum glucose (18-29%), triglyceride (23-30%), LDL cholesterol (7-27%), and total cholesterol (12-26%) levels; no significant changes were noted in the placebo groups. Changes in HDL cholesterol were not significant. The results of this study demonstrate that intake of 1, 3, or 6 g of cinnamon per day reduces serum glucose, triglyceride, LDL cholesterol, and total cholesterol in people with type 2 diabetes and suggest that the inclusion of cinnamon in the diet of people with type 2 diabetes will reduce risk factors associated with diabetes and cardiovascular diseases.
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The causes and control of type 2 diabetes mellitus are not clear, but there is strong evidence that dietary factors are involved in its regulation and prevention. We have shown that extracts from cinnamon enhance the activity of insulin. The objective of this study was to isolate and characterize insulin-enhancing complexes from cinnamon that may be involved in the alleviation or possible prevention and control of glucose intolerance and diabetes. Water-soluble polyphenol polymers from cinnamon that increase insulin-dependent in vitro glucose metabolism roughly 20-fold and display antioxidant activity were isolated and characterized by nuclear magnetic resonance and mass spectroscopy. The polymers were composed of monomeric units with a molecular mass of 288. Two trimers with a molecular mass of 864 and a tetramer with a mass of 1152 were isolated. Their protonated molecular masses indicated that they are A type doubly linked procyanidin oligomers of the catechins and/or epicatechins. These polyphenolic polymers found in cinnamon may function as antioxidants, potentiate insulin action, and may be beneficial in the control of glucose intolerance and diabetes.
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The aim of this study was to determine whether cinnamon extract (CE) would improve the glucose utilization in normal male Wistar rats fed a high-fructose diet (HFD) for three weeks with or without CE added to the drinking water (300 mg/kg/day). In vivo glucose utilization was measured by the euglycemic clamp technique. Further analyses on the possible changes in insulin signaling occurring in skeletal muscle were performed afterwards by Western blotting. At 3 mU/kg/min insulin infusions, the decreased glucose infusion rate (GIR) in HFD-fed rats (60 % of controls, p < 0.01) was improved by CE administration to the same level of controls (normal chow diet) and the improving effect of CE on the GIR of HFD-fed rats was blocked by approximately 50 % by N-monometyl-L-arginine. The same tendency was found during the 30 mU/kg/min insulin infusions. There were no differences in skeletal muscle insulin receptor (IR)-beta, IR substrate (IRS)-1, or phosphatidylinositol (PI) 3-kinase protein content in any groups. However, the muscular insulin-stimulated IR-beta and IRS-1 tyrosine phosphorylation levels and IRS-1 associated with PI 3-kinase in HFD-fed rats were only 70 +/- 9 %, 76 +/- 5 %, and 72 +/- 6 % of controls (p < 0.05), respectively, and these decreases were significantly improved by CE treatment. These results suggest that early CE administration to HFD-fed rats would prevent the development of insulin resistance at least in part by enhancing insulin signaling and possibly via the NO pathway in skeletal muscle.
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In vitro and in vivo animal studies have reported strong insulin-like or insulin-potentiating effects after cinnamon administration. Recently, a human intervention study showed that cinnamon supplementation (1 g/d) strongly reduced fasting blood glucose concentration (30%) and improved the blood lipid profile in patients with type 2 diabetes. The objective of this study was to investigate the effects of cinnamon supplementation on insulin sensitivity and/or glucose tolerance and blood lipid profile in patients with type 2 diabetes. Therefore, a total of 25 postmenopausal patients with type 2 diabetes (aged 62.9 +/- 1.5 y, BMI 30.4 +/- 0.9 kg/m2) participated in a 6-wk intervention during which they were supplemented with either cinnamon (Cinnamomum cassia, 1.5 g/d) or a placebo. Before and after 2 and 6 wk of supplementation, arterialized blood samples were obtained and oral glucose tolerance tests were performed. Blood lipid profiles and multiple indices of whole-body insulin sensitivity were determined. There were no time x treatment interactions for whole-body insulin sensitivity or oral glucose tolerance. The blood lipid profile of fasting subjects did not change after cinnamon supplementation. We conclude that cinnamon supplementation (1.5 g/d) does not improve whole-body insulin sensitivity or oral glucose tolerance and does not modulate blood lipid profile in postmenopausal patients with type 2 diabetes. More research on the proposed health benefits of cinnamon supplementation is warranted before health claims should be made.
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Cinnamon extracts have anti-diabetic effects. Phenolic acids, including hydrocinnamic acids, were identified as major components of cinnamon extracts. Against this background we sought to develop a new anti-diabetic compound using derivatives of hydroxycinnamic acids purified from cinnamon. We purified hydroxycinnamic acids from cinnamon, synthesised a series of derivatives, and screened them for glucose transport activity in vitro. We then selected the compound with the highest glucose transport activity in epididymal adipocytes isolated from male Sprague-Dawley rats in vitro, tested it for glucose-lowering activity in vivo, and studied the mechanisms involved. A naphthalenemethyl ester of 3,4-dihydroxyhydrocinnamic acid (DHH105) showed the highest glucose transport activity in vitro. Treatment of streptozotocin-induced diabetic C57BL/6 mice and spontaneously diabetic ob/ob mice with DHH105 decreased blood glucose levels to near normoglycaemia. Further studies revealed that DHH105 increased the maximum speed of glucose transport and the translocation of glucose transporter 4 (GLUT4, now known as solute carrier family 2 [facilitated glucose transporter], member 4 [SLC2A4]) in adipocytes, resulting in increased glucose uptake. In addition, DHH105 enhanced phosphorylation of the insulin receptor-beta subunit and insulin receptor substrate-1 in adipocytes, both in vitro and in vivo. This resulted in the activation of phosphatidylinositol 3-kinase and Akt/protein kinase B, contributing to the translocation of GLUT4 to the plasma membrane. We conclude that DHH105 lowers blood glucose levels through the enhancement of glucose transport, mediated by an increase in insulin-receptor signalling. DHH105 may be a valuable candidate for a new anti-diabetic drug.
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Proanthocyanidins (PAs) have been shown to have potential health benefits. However, no data exist concerning their dietary intake. Therefore, PAs in common and infant foods from the U.S. were analyzed. On the bases of our data and those from the USDA's Continuing Survey of Food Intakes by Individuals (CSFII) of 1994-1996, the mean daily intake of PAs in the U.S. population (>2 y old) was estimated to be 57.7 mg/person. Monomers, dimers, trimers, and those above trimers contribute 7.1, 11.2, 7.8, and 73.9% of total PAs, respectively. The major sources of PAs in the American diet are apples (32.0%), followed by chocolate (17.9%) and grapes (17.8%). The 2- to 5-y-old age group (68.2 mg/person) and men >60 y old (70.8 mg/person) consume more PAs daily than other groups because they consume more fruit. The daily intake of PAs for 4- to 6-mo-old and 6- to 10-mo-old infants was estimated to be 1.3 mg and 26.9 mg, respectively, based on the recommendations of the American Academy of Pediatrics. This study supports the concept that PAs account for a major fraction of the total flavonoids ingested in Western diets.
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Previous studies of patients with type 2 diabetes showed that cinnamon lowers fasting serum glucose, triacylglycerol, and LDL- and total cholesterol concentrations. We aimed to study the effect of cinnamon on the rate of gastric emptying, the postprandial blood glucose response, and satiety in healthy subjects. The gastric emptying rate (GER) was measured by using standardized real-time ultrasonography. Fourteen healthy subjects were assessed by using a crossover trial. The subjects were examined after an 8-h fast if they had normal fasting blood glucose concentrations. GER was calculated as the percentage change in the antral cross-sectional area 15-90 min after ingestion of 300 g rice pudding (GER1) or 300 g rice pudding and 6 g cinnamon (GER2). The median value of GER1 was 37%, and that of GER2 was 34.5%. The addition of cinnamon to the rice pudding significantly delayed gastric emptying and lowered the postprandial glucose response (P < 0.05 for both). The reduction in the postprandial blood glucose concentration was much more noticeable and pronounced than was the lowering of the GER. The effect of cinnamon on satiety was not significant. The intake of 6 g cinnamon with rice pudding reduces postprandial blood glucose and delays gastric emptying without affecting satiety. Inclusion of cinnamon in the diet lowers the postprandial glucose response, a change that is at least partially explained by a delayed GER.
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To perform a meta-analysis of randomized controlled trials of cinnamon to better characterize its impact on glucose and plasma lipids. A systematic literature search through July 2007 was conducted to identify randomized placebo-controlled trials of cinnamon that reported data on A1C, fasting blood glucose (FBG), or lipid parameters. The mean change in each study end point from baseline was treated as a continuous variable, and the weighted mean difference was calculated as the difference between the mean value in the treatment and control groups. A random-effects model was used. Five prospective randomized controlled trials (n = 282) were identified. Upon meta-analysis, the use of cinnamon did not significantly alter A1C, FBG, or lipid parameters. Subgroup and sensitivity analyses did not significantly change the results. Cinnamon does not appear to improve A1C, FBG, or lipid parameters in patients with type 1 or type 2 diabetes.
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Common (Cinnamomum verum, C. zeylanicum) and cassia (C. aromaticum) cinnamon have a long history of use as spices and flavouring agents. A number of pharmacological and clinical effects have been observed with their use. The objective of this study was to systematically review the scientific literature for preclinical and clinical evidence of safety, efficacy, and pharmacological activity of common and cassia cinnamon. Using the principles of evidence-based practice, we searched 9 electronic databases and compiled data according to the grade of evidence found. One pharmacological study on antioxidant activity and 7 clinical studies on various medical conditions were reported in the scientific literature including type 2 diabetes (3), Helicobacter pylori infection (1), activation of olfactory cortex of the brain (1), oral candidiasis in HIV (1), and chronic salmonellosis (1). Two of 3 randomized clinical trials on type 2 diabetes provided strong scientific evidence that cassia cinnamon demonstrates a therapeutic effect in reducing fasting blood glucose by 10.3%-29%; the third clinical trial did not observe this effect. Cassia cinnamon, however, did not have an effect at lowering glycosylated hemoglobin (HbA1c). One randomized clinical trial reported that cassia cinnamon lowered total cholesterol, low-density lipoprotein cholesterol, and triglycerides; the other 2 trials, however, did not observe this effect. There was good scientific evidence that a species of cinnamon was not effective at eradicating H. pylori infection. Common cinnamon showed weak to very weak evidence of efficacy in treating oral candidiasis in HIV patients and chronic salmonellosis.
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We performed a meta-analysis of randomized controlled trials to assess the effect of metformin on metabolic parameters and the incidence of new-onset diabetes in persons at risk for diabetes. We performed comprehensive English- and non-English-language searches of EMBASE, MEDLINE, and CINAHL databases from 1966 to November of 2006 and scanned selected references. We included randomized trials of at least 8 weeks duration that compared metformin with placebo or no treatment in persons without diabetes and evaluated body mass index, fasting glucose, fasting insulin, calculated insulin resistance, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, and the incidence of new-onset diabetes. Pooled results of 31 trials with 4570 participants followed for 8267 patient-years showed that metformin reduced body mass index (-5.3%, 95% confidence interval [CI], -6.7--4.0), fasting glucose (-4.5%, CI, -6.0--3.0), fasting insulin (-14.4%, CI, -19.9--8.9), calculated insulin resistance (-22.6%, CI, -27.3--18.0), triglycerides (-5.3%, CI, -10.5--0.03), and low-density lipoprotein cholesterol (-5.6%, CI, -8.3--3.0%), and increased high-density lipoprotein cholesterol (5.0%, CI, 1.6-8.3) compared with placebo or no treatment. The incidence of new-onset diabetes was reduced by 40% (odds ratio 0.6; CI, 0.5-0.8), with an absolute risk reduction of 6% (CI, 4-8) during a mean trial duration of 1.8 years. Metformin treatment in persons at risk for diabetes improves weight, lipid profiles, and insulin resistance, and reduces new-onset diabetes by 40%. The long-term effect on morbidity and mortality should be assessed in future trials.
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High oxalate intake resulting from consuming supplemental doses of cinnamon and turmeric may increase risk of hyperoxaluria, a significant risk factor for urolithiasis. This study assessed urinary oxalate excretion from supplemental doses of cinnamon and turmeric as well as changes in fasting plasma glucose, cholesterol, and triacylglycerol concentrations. Eleven healthy subjects, aged 21-38 y, participated in an 8-wk, randomly assigned, crossover study that involved the ingestion of supplemental doses of cinnamon and turmeric for 4-wk periods that provided 55 mg oxalate/d. Oxalate load tests, which entailed the ingestion of a 63-mg dose of oxalate from the test spices, were performed after each 4-wk experimental period and at the study onset with water only (control treatment). Fasting plasma glucose and lipid concentrations were also assessed at these time points. Compared with the cinnamon and control treatments, turmeric ingestion led to a significantly higher urinary oxalate excretion during the oxalate load tests. There were no significant changes in fasting plasma glucose or lipids in conjunction with the 4-wk periods of either cinnamon or turmeric supplementation. The percentage of oxalate that was water soluble differed markedly between cinnamon (6%) and turmeric (91%), which appeared to be the primary cause of the greater urinary oxalate excretion/oxalate absorption from turmeric. The consumption of supplemental doses of turmeric, but not cinnamon, can significantly increase urinary oxalate levels, thereby increasing risk of kidney stone formation in susceptible individuals.
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The purpose of this study was to determine the effects of supplementation with a water-soluble cinnamon extract (Cinnulin PF(R)) on body composition and features of the metabolic syndrome. Twenty-two subjects with prediabetes and the metabolic syndrome (mean +/- SD: age, BMI, systolic blood pressure [SBP], fasting blood glucose [FBG]: 46.0 +/- 9.7 y; 33.2 +/- 9.3 kg/m2; 133 +/- 17 mm Hg; 114.3 +/- 11.6 mg/dL) were randomly assigned to supplement their diet with either Cinnulin PF(R) (500 mg/d) or a placebo for 12-weeks. Main outcome measures were changes in FBG, SBP, and body composition measured after 12-weeks of supplementation. The primary statistical analyses consisted of two factor (group x time), repeated-measures ANOVA for between group differences over time. In all analyses, an intent-to-treat approach was used and significance was accepted at P < 0.05. Subjects in the Cinnulin PF(R) group had significant decreases in FBG (-8.4%: 116.3 +/- 12.8 mg/dL [pre] to 106.5 +/- 20.1 mg/dL [post], p < 0.01), SBP (-3.8%: 133 +/- 14 mm Hg [pre] to 128 +/- 18 mm Hg [post], p < 0.001), and increases in lean mass (+1.1%: 53.7 +/- 11.8 kg [pre] to 54.3 +/- 11.8 kg [post], p < 0.002) compared with the placebo group. Additionally, within-group analyses uncovered small, but statistically significant decreases in body fat (-0.7%: 37.9 +/- 9.2% [pre] to 37.2 +/- 8.9% [post], p < 0.02) in the Cinnulin PF(R) group. No significant changes in clinical blood chemistries were observed between groups over time. These data support the efficacy of Cinnulin PF(R) supplementation on reducing FBG and SBP, and improving body composition in men and women with the metabolic syndrome and suggest that this naturally-occurring spice can reduce risk factors associated with diabetes and cardiovascular diseases.
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Proanthocyanidins (syn condensed tannins) are complex flavonoid polymers naturally present in cereals, legume seeds and particularly abundant in some fruits and fruit juices. They share some common structural features—phenolic nature and high molecular weight—with phenolic polymers found in black tea and red wine (called here tannin‐like compounds). The polymeric nature of proanthocyanidins makes their analysis and estimation in food difficult. For this reason, little is known about their consumption, although they likely contribute a large part of the daily polyphenol intake. They also share common physicochemical properties: they form stable complexes with metal ions and with proteins and are, like other polyphenols, good reducing agents. Many of their biological effects of nutritional interest derive from these properties. As metal ion chelators, they influence the bioavailability of several minerals. The nutritional significance of the non‐specific complexation of proteins is less clear. As reducing agents, they may participate in the prevention of cancers, both of the digestive tract and inner organs. They may also protect LDLs against oxidation and inhibit platelet aggregation and therefore prevent cardiovascular diseases. In vitro , animal and human studies on the prevention of these chronic diseases are reviewed with particular attention to wine and tea polyphenols. The lack of data on their bioavailability and the paucity of human studies are emphasised. © 2000 Society of Chemical Industry
Article
In vitro and in vivo animal studies have reported strong insulin-like or insulin-potentiating effects after cinnamon administration. Recently, a human intervention study showed that cinnamon supplementation (1 g/d) strongly reduced fasting blood glucose concentration (30%) and improved the blood lipid profile in patients with type 2 diabetes. The objective of this study was to investigate the effects of cinnamon supplementation on insulin sensitivity and/or glucose tolerance and blood lipid profile in patients with type 2 diabetes. Therefore, a total of 25 postmenopausal patients with type 2 diabetes (aged 62.9 +/- 1.5 y, BMI 30.4 +/- 0.9 kg/m(2)) participated in a 6-wk intervention during which they were supplemented with either cinnamon (Cinnamomum cassia, 1.5 g/d) or a placebo. Before and after 2 and 6 wk of supplementation, arterialized blood samples were obtained and oral glucose tolerance tests were performed. Blood lipid profiles and multiple indices of whole-body insulin sensitivity were determined. There were no time X treatment interactions for whole-body insulin sensitivity or oral glucose tolerance. The blood lipid profile of fasting subjects did not change after cinnamon supplementation. We conclude that cinnamon supplementation (1.5 g/d) does not improve whole-body insulin sensitivity or oral glucose tolerance and does not modulate blood lipid profile in postmenopausal patients with type 2 diabetes. More research on the proposed health benefits of cinnamon supplementation is warranted before health claims should be made.
Article
Proanthocyanidins (syn condensed tannins) are complex flavonoid polymers naturally present in cereals, legume seeds and particularly abundant in some fruits and fruit juices. They share some common structural features—phenolic nature and high molecular weight—with phenolic polymers found in black tea and red wine (called here tannin-like compounds). The polymeric nature of proanthocyanidins makes their analysis and estimation in food difficult. For this reason, little is known about their consumption, although they likely contribute a large part of the daily polyphenol intake. They also share common physicochemical properties: they form stable complexes with metal ions and with proteins and are, like other polyphenols, good reducing agents. Many of their biological effects of nutritional interest derive from these properties. As metal ion chelators, they influence the bioavailability of several minerals. The nutritional significance of the non-specific complexation of proteins is less clear. As reducing agents, they may participate in the prevention of cancers, both of the digestive tract and inner organs. They may also protect LDLs against oxidation and inhibit platelet aggregation and therefore prevent cardiovascular diseases. In vitro, animal and human studies on the prevention of these chronic diseases are reviewed with particular attention to wine and tea polyphenols. The lack of data on their bioavailability and the paucity of human studies are emphasised.© 2000 Society of Chemical Industry