Systematic Review of Herbs and Dietary Supplements for Glycemic Control in Diabetes

Abstract

OBJECTIVE -To conduct a systematic review of the published literature on the efficacy and safety of herbal therapies and vitamin/mineral supplements for glucose control in patients with diabetes.RESEARCH DESIGN AND METHODS -We conducted an electronic literature search of MEDLINE, OLDMEDLINE, Cochrane Library Database, and HealthSTAR, from database inception to May 2002, in addition to performing hand searches and consulting with experts in the field. Available clinical studies published in the English language that used human participants and examined glycemic control were included. Data were extracted in a standardized manner, and two independent investigators assessed methodological quality of randomized controlled trials using the Jadad scale.RESULTS -A total of 108 trials examining 36 herbs (single or in combination) and 9 vitamin/ mineral supplements, involving 4,565 patients with diabetes or impaired glucose tolerance, met the inclusion criteria and were analyzed. There were 58 controlled clinical trials involving individuals with diabetes or impaired glucose tolerance (42 randomized and 16 nonrandomized trials). Most studies involved patients with type 2 diabetes. Heterogeneity and the small number of studies per supplement precluded formal meta-analyses. Of these 58 trials, the direction of the evidence for improved glucose control was positive in 76% (44 of 58). Very few adverse effects were reported.CONCLUSIONS -There is still insufficient evidence to draw definitive conclusions about the efficacy of individual herbs and supplements for diabetes; however, they appear to be generally safe. The available data suggest that several supplements may warrant further study. The best evidence for efficacy from adequately designed randomized controlled trials (RCTs) is available for Coccinia indica and American ginseng. Chromium has been the most widely studied supplement. Other supplements with positive preliminary results include Gymnema sylvestre, Aloe vera, vanadium, Momordica charantia, and nopal. Diabetes Care 26:1277-1294, 2003D iabetes is a predominant public health concern, affecting ϳ16 million persons in the U.S. The disease causes substantial morbidity, mortality, and long-term complications and remains an important risk factor for cardiovascular disease. With increasing rates of childhood and adult obesity, diabetes is likely to become even more prevalent over the coming decade (1).In response to the increasing use of complementary and alternative medicine (CAM) among the general public (2,3), the American Diabetes Association issued a Position Statement in 2001 on "Unproven Therapies" that encouraged health care providers to ask their patients about alternative therapies and practices, evaluate each therapy's effectiveness, be cognizant of any potential harm to patients, and acknowledge circumstances in which new and innovative diagnostic or therapeutic measures might be provided to patients (4).Recently, two national surveys have examined CAM use among those with diabetes. One study, using 1996 Me...

Traditionally used plants in diabetes therapy: phytotherapeutics as inhibitors of alpha-amylase activity

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Chamomile Consumption and Mortality: A Prospective Study of Mexican Origin Older Adults

“…It is, however, unclear how chamomile use is associated with reduced mortality. Recent studies of chamomile showed potential benefits in treating hyperglycemia, diabetic complications (Kato et al, 2008;Yeh, Eisenberg, Kaptchuk, & Phillips, 2003) and anxiety disorder (Amsterdam et al, 2009). Other potential pathways include its cholesterol-lowering, antioxidant, and anti-platelet properties which may convey cardiovascular benefits; however, we did not observe a positive effect on cardiovascular disease mortality after controlling for other factors.…”

Risks and benefits of commonly used herbal medicines in Mexico

“…Soluble fibers, including pectins, gums, and mucilages, increase the viscosity of food in the gut, slowing or reducing sugar absorption. The effect of soluble fiber in reducing serum glucose concentrations is a proposed mechanism of action for the herbal hypoglycemic nopal (De Smet, 2002;Yeh et al, 2003). However, fiber content is not the sole mechanism of action, since fasting blood glucose levels are affected.…”

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“…Hyperlipidemia Diabetes. (Syed et al, 1996;Yeh et al, 2003;Langmead et al, 2004) Hypoglycemia Hypokalemia Decrease platelet aggregation Prolog bleeding time Diarrhea and loss of water and electrolytes (Shaw et al, 1997;De Smet, 2002;Garnier et al, 2006) Hypoglycemic drugs Cardiac glycosides (Shaw et al, 1997;Federici et al, 2005;Bush et al 2007) …”