Bitter Melon for Type 2 Diabetes, An Update
The challenge of managing type 2 diabetes has prompted some people to explore alternative treatment options, and one of them, despite its name, may be a sweet one. Bitter melon is a popular natural remedy for type 2 diabetes among traditional medicine practitioners, and the subject of various research endeavors that present varying results.
Could bitter melon help you?
Bitter melon (Momordica charantia), also known as bitter gourd, is alternately referred to as a vegetable and as the fruit of the Momordica charantia plant. In either case, bitter melon grows in tropical and subtropical regions and lives up to its name because of its extremely bitter taste.
Numerous studies in both animals and humans have indicated that bitter melon could be helpful in the management of blood sugar among individuals with type 2 diabetes. One reason for this interest in bitter melon is the finding of a research team, published in 2008, concerning four bioactive components identified in bitter melon.
In that study, investigators reported that the components seemed to active a protein (AMPK) known to be involved with metabolism and with the ability of the body's cells to take in glucose. The study's authors noted that bitter melon was not associated with side effects and that Chinese medicine practitioners had been using the vegetable for hundreds of years and seen good results.
Among the studies of bitter melon and diabetes is a recent open-label trial in which 42 adults with metabolic syndrome were given 4.8 grams of wild bitter gourd daily in capsule form for three months. Metabolic syndrome (MetS) is a combination of five risk factors that can increase the risk of developing type 2 diabetes fivefold: abdominal fat, high blood pressure, high blood sugar, low high-density lipoprotein (HDL) cholesterol, and high triglycerides.
All the participants were checked monthly during treatment and then for three months posttreatment. Metabolic syndrome incidence rate declined progressively for the first three months of treatment and reached a significant difference (19%) at the end of treatment and remained so (16.7%) at the end of month 4 before diminishing at months 5 and 6.
This study was "the first report to show that WBG [wild bitter gourd] improved MetS in humans which provides a firm base for further andomzied controlled trials." The authors also found that bitter melon significantly reduced abdominal fat and did not cause side effects.
In the Journal of Medicinal Food, a group of California researchers explored the impact of bitter melon extracts in diabetic and normal rats. Overall, bitter melon "powerfully lowered glucose levels" in diabetic rats and "exhibited beneficial effects in the regulation of blood glucose" in healthy rats. In fact, bitter melon extract reduced blood glucose more than did metformin (67% and 63% vs 54%, respectively).
Not every study has been positive, however.
In a new review published in Cochrane Database Systemic Reviews, the authors evaluated the results of four randomized controlled trials of bitter melon and type 2 diabetes. The trials compared bitter melon with placebo, a drug, or a non-drug intervention.
Overall, the reviewers reported bitter melon did not result in a significant difference in glycemic control when compared with placebo or the antidiabetes drugs metformin or glibenclamide. They also noted bitter melon was not associated with any serious side effects and concluded "there is insufficient evidence on the effects of momordica charantia for type 2 diabetes mellitus."
At the same time, another new study reported on the potential of a component of bitter melon in the fight against diabetes and its complications. The authors noted that EMCD, purified from bitter melon, has potent anti-inflammatory properties, and that insulin resistance is closely associated with chronic inflammation.
In a laboratory setting, the authors found that EMCD demonstrated abilities that "suggest it to be a potential agent in treating diabetic complications and other inflammation-related disorders." They also pointed out that when EMCD was compared with EGCG, a catechin found in green tea that has anti-inflammatory abilities, EMCD was superior.
Given the promising results of much of the research to this point, bitter melon will continue to be the subject of more investigations. If you have type 2 diabetes and are interested in taking bitter melon, it is available as a supplement, but be sure to consult your healthcare provider before starting any supplement program.
Cheng HL et al. EMCD, a hypoglycemic triterpene isolated from Momordica charantia wild variant, attenuates TNF-a-induced inflammation in FL83B cells in an AMP-activated protein kinase-independent manner. European Journal of Pharmacology 2012 Aug 15; 689(1-3): 241-48
Clouatre DL et al. Bitter melon extracts in diabetic and normal rats favorably influence blood glucose and blood pressure regulation. Journal of Medicinal Food 2011 Dec; 14(12): 1496-504
Garvan Institute. "A tonne of bitter melon produces sweet results for diabetes."
Ooi CP et al. Momordica charantia for type 2 diabetes mellitus. Cochrane Database Systemic Reviews 2012 Aug 15; 8:CD007845
Tsai CH et al. Wild bitter gourd improves metabolic syndrome: a preliminary dietary supplementation trial. Nutrition Journal 2012 Jan 13; 11:4.
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