Parts Used & Where Grown
Gymnema sylvestre is a woody climbing plant that grows in the tropical forests of central and southern India. The leaves are used in herbal medicine preparations. G. sylvestre is known as "periploca of the woods" in English and meshasringi (meaning "ram's horn") in Sanskrit. The leaves, when chewed, interfere with the ability to taste sweetness, which explains the Hindi name gurmar-"destroyer of sugar."
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For over a decade, our team has combed through thousands of research articles published in reputable journals. To help you make educated decisions, and to better understand controversial or confusing supplements, our medical experts have digested the science into these three easy-to-follow ratings. We hope this provides you with a helpful resource to make informed decisions towards your health and well-being.
3 Stars Reliable and relatively consistent scientific data showing a substantial health benefit.
2 Stars Contradictory, insufficient, or preliminary studies suggesting a health benefit or minimal health benefit.
1 Star For an herb, supported by traditional use but minimal or no scientific evidence. For a supplement, little scientific support.
This supplement has been used in connection with the following health conditions:
Type 1 Diabetes
800 mg per day of an herbal extract standardized for 25% gymnemic acids
Test tube and animal studies have found several mechanisms by which gymnema may help normalize blood sugar control in diabetics.1 In a controlled trial with people with type 1 diabetes, 400 mg per day of gymnema extract reduced requirements for insulin.2 Whether the extract used in this study was standardized for active constituents is unclear. Recently, a preliminary trial found improved blood sugar levels after three months in a group of people with type 1 and type 2 diabetes who took 800 mg per day of an extract standardized for 25% gymnemic acids.3 Gymnema is not a substitute for insulin, but insulin amounts may need to be lowered in order to avoid hypoglycemia while taking gymnema.
Type 2 Diabetes
800 mg daily of an herbal extract standardized for 25% gymnemic acids
Gymnema may stimulate the pancreas to produce insulin in people with type 2 diabetes. Gymnema also improves the ability of insulin to lower blood sugar in people with both type 1 and type 2 diabetes. So far, no double-blind trials have confirmed the efficacy of gymnema for people with any type of diabetes. However, a preliminary study of type 2 diabetics reported that 400 mg per day of gymnema extract taken for periods of 18 months or longer resulted in improvement, according to diabetes blood tests, and allowed reduction of diabetic medications.4 Improvements in blood glucose levels were also seen in patients with type 2 diabetes who received 1 g per day of a specific gymnema extract (Om Santal Adivasi) for two months.5 In a controlled trial with type 1 (insulin-dependent) diabetics, a similar amount of gymnema extract reduced requirements for insulin.6 Whether the extract used in these studies was standardized for active constituents is unclear. Recently, a preliminary trial found improved blood sugar levels after three months in a group of type 1 and type 2 diabetics who took 800 mg per day of an extract standardized for 25% gymnemic acids.7 Gymnema is not a substitute for insulin, but insulin amounts may need to be lowered while taking gymnema to avoid hypoglycemia.
How It Works
How It Works
The hypoglycemic (blood sugar-lowering) action of gymnema leaves was first documented in the late 1920s.8 This action is attributed to members of a family of substances called gymnemic acids.9 , 10 Gymnema leaves raise insulin levels, according to research in healthy volunteers.11 Based on animal studies, this may be due to regeneration of the cells in the pancreas that secrete insulin,12 , 13 or by increasing the flow of insulin from these cells.14 Other animal research shows that gymnema can also reduce glucose absorption from the intestine,15 improve uptake of glucose into cells, and prevent adrenal hormones from stimulating the liver to produce glucose, thereby reducing blood sugar levels.16 , 17
Other animal studies have shown that extracts of gymnema leaves can lower serum cholesterol and triglycerides and prevent weight gain,18 , 19 , 20 , 21 but these effects have not been tested in humans. When placed directly on the tongue, gurmarin, another constituent of the leaves, and gymnemic acid have been shown to block the ability in humans to taste sweets.22 , 23
How to Use It
Clinical trials with diabetics in India have used 400 mg per day of a water-soluble acidic fraction of the gymnema leaves. The gymnemic acid content of this extract is not clear. A recent preliminary trial in the United States reported promising results in a group of type 1 and type 2 diabetics who took 800 mg per day of an extract standardized for 25% gymnemic acids.24 Traditionally, 2 to 4 grams per day of the leaf powder is used.
Interactions with Supplements, Foods, & Other Compounds
Interactions with Medicines
Certain medicines interact with this supplement.
Replenish Depleted Nutrients
Reduce Side Effects
Potential Negative Interaction
Herbs such as Gymnema sylvestre will often improve blood-sugar control in diabetics.The interaction is supported by preliminary, weak, fragmentary, and/or contradictory scientific evidence.
Although no interactions have been reported, gymnema may decrease the required daily dose of insulin.25 Therefore, people currently using insulin for the treatment of diabetes should discuss the use of this herb with their healthcare professional.The interaction is supported by preliminary, weak, fragmentary, and/or contradictory scientific evidence.
Used at the amounts suggested, gymnema is generally safe and devoid of side effects. The safety of gymnema during pregnancy and breast-feeding has not yet been determined. People with diabetes should only use gymnema to lower blood sugar under the clinical supervision of a healthcare professional. Gymnema cannot be used in place of insulin to control blood sugar by people with either type 1 or type 2 diabetes .
1. [No authors listed]Gymnema sylvestre. Altern Med Rev 1999;4:46-7.
2. Shanmugasundaram ERB, Rajeswari G, Baskaran K, et al. Use of Gymnema sylvestre leaf extract in the control of blood glucose insulin-dependent diabetes mellitus. J Ethnopharmacol 1990;30:281-94.
3. Joffe DJ, Freed SH. Effect of extended release gymnema sylvestre leaf extract (Beta Fast GXR) alone or in combination with oral hypoglycemics or insulin regimens for type 1 and type 2 diabetes. Diabetes In: Control Newsletter 2001;76:no page number.
4. Baskaran K, Ahmath BK, Shanmugasundaram KR, Shanmugasundaram ERB. Antidiabetic effect of a leaf extract from Gymnema sylvestre in non-insulin-dependent diabetes mellitus patients. J Ethnopharmacol 1990;30:295-305.
5. Al-Romaiyan A, Liu B, Asare-Anane H, et al. A novel Gymnema sylvestre extract stimulates insulin secretion from human islets in vivo and in vitro. Phytother Res 2010;24:1370-6.
6. Shanmugasundaram ERB, Rajeswari G, Baskaran K, et al. Use of Gymnema sylvestre leaf extract in the control of blood glucose insulin-dependent diabetes mellitus. J Ethnopharmacol 1990;30:281-94.
7. Joffe DJ, Freed SH. Effect of extended release gymnema sylvestre leaf extract (Beta Fast GXR) alone or in combination with oral hypoglycemics or insulin regimens for type 1 and type 2 diabetes. Diabetes In Control Newsletter 2001;76:no page number.
8. Mhasker KS, Caius JF. A study of Indian medicinal plants. II. Gymnema sylvestre R.Br. Indian J Med Res Memoirs 1930;16:2-75.
9. Sugihara Y, Nojima H, Matsuda H, et al. Antihyperglycemic effects of gymnemic acid IV, a compound derived from Gymnema sylvestre leaves in streptozotocin-diabetic mice. J Asian Nat Prod Res 2000;2:321-7.
10. Murakami N, Murakami T, Kadoya M, et al. New hypoglycemic constituents in "gymnemic acid" from Gymnema sylvestre. Chem Pharm Bull (Tokyo) 1996;44:469-71.
11. Shanmugasundaram KR, Panneerselvam C, Sumudram P, Shanmugasundaram ERB. Insulinotropic activity of G. sylvestre, R.Br. and Indian medicinal herb used in controlling diabetes mellitus. Pharmacol Res Commun 1981;13:475-86.
12. Shanmugasundaram ER, Gopinath KL, Radha Shanmugasundaram K, Rajendran VM. Possible regeneration of the islets of Langerhans in streptozotocin diabetic rats given Gymnema sylvestre leaf extracts. J Ethnopharmacol 1990;30:265-79.
13. Prakash AO, Mather S, Mather R. Effect of feeding Gymnema sylvestre leaves on blood glucose in beryllium nitrate treated rats. J Ethnopharmacol 1986;18:143-4.
14. Persaud SJ, Al-Majed H, Raman A, Jones PM. Gymnema sylvestre stimulates insulin release in vitro by increased membrane permeability. J Endocrinol 1999;163:207-12.
15. Shimizu K, Iino A, Nakajima J, et al. Suppression of glucose absorption by some fractions extracted from Gymnema sylvestre leaves. J Vet Med Sci1997;59:245-51.
16. [No authors listed]. Gymnema sylvestre. Alt Med Rev 1999;4:46-7 [review].
17. Gholap S, Kar A. Effects of Inula racemosa root and Gymnema sylvestre leaf extracts in the regulation of corticosteroid induced diabetes mellitus: involvement of thyroid hormones. Pharmazie 2003;58:413-5.
18. Bishayee A, Chatterjee M. Hypolipidemic and antiatherosclerotic effects of oral Gymnema sylvestre R.Br. leaf extract in albino rats fed on a high fat diet. Phytother Res 1994;8:118-20.
19. Shigematsu N, Asano R, Shimosaka M, Okazaki M. Effect of administration with the extract of Gymnema sylvestre R. Br leaves on lipid metabolism in rats. Biol Pharm Bull 2001;24:713-7.
20. Shigematsu N, Asano R, Shimosaka M, Okazaki M. Effect of long term-administration with Gymnema sylvestre R. BR on plasma and liver lipid in rats. Biol Pharm Bull 2001;24:643-9.
21. Nakamura Y, Tsumura Y, Tonogai Y, Shibata T. Fecal steroid excretion is increased in rats by oral administration of gymnemic acids contained in Gymnema sylvestre leaves. J Nutr 1999;129:1214-22.
22. Min BC, Sakamoto K. Influence of sweet suppressing agent on gustatory brain evoked potentials generated by taste stimuli. Appl Human Sci 1998;17:9-17.
23. Gent JF, Hettinger TP, Frank ME, Marks LE. Taste confusions following gymnemic acid rinse. Chem Senses 1999;24:393-403.
24. Joffe DJ, Freed SH. Effect of extended release gymnema sylvestre leaf extract (Beta Fast GXR) alone or in combination with oral hypoglycemics or insulin regimens for type 1 and type 2 diabetes. Diabetes In Control Newsletter 2001;76:no page number.
25. Shanmugasundaram ER, Rajeswari G, Baskaran K, et al. Use of Gymnema sylvestre leaf extract in the control of blood glucose in insulin-dependent diabetes mellitus. J Ethnopharmacol 1990;30:281-94.
Last Review: 09-04-2013
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