Common names: Gurmarbooti, Gurmar
Botanical name: Gymnema sylvestre
Parts used and 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
rams horn) in Sanskrit. The leaves, when chewed, interfere with the
ability to taste sweetness, which explains the Hindi name gurmardestroyer
of sugar.
Gymnema has been used in connection with the following condition
(refer to the individual health concern for
complete information):
Historical or traditional use
(may or may not be supported by scientific
studies)
Gymnema has been used in India for the treatment of type 1 and
type 2 diabetes for over 2,000 years. The leaves were also used for
stomach ailments, constipation, water retention, and liver disease.
Active constituents
The hypoglycemic (blood sugar-lowering) action of gymnema leaves was
first documented in the late 1920s.1 This action is
attributed to members of a family of substances called gymnemic acids.2
3 Gymnema leaves raise insulin levels, according to research
in healthy volunteers.4 Based on animal studies, this may be
due to regeneration of the cells in the pancreas that secrete insulin,5
6 or by increasing the flow of insulin from these cells.7
Other animal research shows that gymnema can also reduce glucose
absorption from the intestine,8 improve uptake of glucose
into cells, and prevent adrenal hormones from stimulating the liver to
produce glucose, thereby reducing blood sugar levels.9
10
Other animal studies have shown that extracts of gymnema leaves can
lower serum cholesterol and triglycerides and prevent weight gain,11
12 13 14 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.15 16
How much is usually taken?
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.17 Traditionally, 2 to 4 grams per day of the
leaf powder is used.
Are there any side effects or
interactions?
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.
Are there any drug
interactions?
Certain medicines may interact with gymnema. Refer to drug interactions
for a list of those medicines.
References
1. Mhasker KS, Caius JF. A study of Indian
medicinal plants. II. Gymnema sylvestre R.Br. Indian J Med
Res Memoirs 1930;16:275.
2. 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;2:3217.
3. Murakami N, Murakami T, Kadoya M, et al. New
hypoglycemic constituents in "gymnemic acid" from Gymnema sylvestre.
Chem Pharm Bull (Tokyo) 1996;44:46971.
4. 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;13:47586.
5. 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;30:26579.
6. Prakash AO, Mather S, Mather R. Effect of
feeding Gymnema sylvestre leaves on blood glucose in beryllium
nitrate treated rats. J Ethnopharmacol 1986;18:1434.
7. Persaud SJ, Al-Majed H, Raman A, Jones PM.
Gymnema sylvestre stimulates insulin release in vitro by increased
membrane permeability. J Endocrinol 1999;163:20712.
8. Shimizu K, Iino A, Nakajima J, et al.
Suppression of glucose absorption by some fractions extracted from
Gymnema sylvestre leaves. J Vet Med Sci 1997;59:24551.
9. [No authors listed]. Gymnema sylvestre. Alt
Med Rev 1999;4:467 [review].
10. 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;58:4135.
11. 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;8:11820.
12. 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;24:7137.
13. 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;24:6439.
14. 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;129:121422.
15. Min BC, Sakamoto K. Influence of sweet
suppressing agent on gustatory brain evoked potentials generated by
taste stimuli. Appl Human Sci 1998;17:917.
16. Gent JF, Hettinger TP, Frank ME, Marks LE.
Taste confusions following gymnemic acid rinse. Chem Senses
1999;24:393403.
17. 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.
