Single Herbs/Plant Derivatives For Glycemic Control

Name

Mechanism of Action

Adverse Effects

Level of Evidence

Any Benefit?

Ivy Gourd (Coccinia indica)

Insulin-mimetic effects

 

None reported

Level I, A

*Potentially, but more research needed

Ginseng Species (Panax, Siberian, American, Japanese)

Decreases CHO absorption into portal system, increased transport/uptake via nitric oxide, increases glycogen storage, modulates insulin secretion

None reported; mild insomnia in 1 case

Level I, A

*Possible hypoglycemic effect, but larger and more long-term studies needed

Garlic (allium sativum) and onion (allium cepum)

Increases secretion or decreases degradation of insulin, increases glutathionine peroxidase activity, improves glycogen storage

None reported

Level I, C

Inconclusive; conflicting data

Holy Basil (Ocimum Sanctum)

Hypoglycemic effects, but unknown. Possibly by enhanced beta-cell function and insulin secretion

None reported

Level III, C

Inconclusive; more research needed

Fenugreek (Trigonella foenum graecum)

Delays gastric emptying, slows CHO absorption, inhibits glucose transport from fiber content, increases GLUT receptors, modulates peripheral glucose metabolism

None reported

Level II-2, C

Potentially, but more research needed

Bauhinia forficata and Myrcia uniflora

“Vegetable insulin”

None reported

Level I

Preliminary results show no benefit

Fig Leaf (Ficus carica)

Hypoglycemic and hypolipidemic, but not conclusive. Potential effects on peripheral glucose metabolism, non-insulin mediated?

None reported

Level III, C

Inconclusive; more research needed

Nopal (Opuntia streptacantha)

High soluble fiber/pectin which may delay glucose absorption. Improves insulin sensitivity?

None reported

Level III, C

*Possible hypoglycemic effect, but more long-term studies needed

Milk Thistle (Silibum marianum)

Antioxidant capabilities, has effects on hepatocyte stabilization, decreases glutathione oxidation, restores malondialdehyde levels. Benefits for insulin resistance secondary to liver damage

None reported

Level III, C

Inconclusive; more research needed

Gymnema sylvestre (“gurmar”= destroyer of sugar)

Postulated that increases glucose uptake/utilization, increases insulin release through cell permeability, increases beta-cell number and stimulates function

None reported

Level II-1, C

*Suggestive, but inconclusive

Mormordica charantia (balsam pear, karela, bitter melon)

Theorized to increase insulin secretion, tissue glucose uptake, liver muscle glycogen synthesis, glucose oxidation, and decrease hepatic gluconeogenesis

None reported

Level III, C

*Potentially, but more research needed

Aloe vera

Contains glucomannan (hydrosoluble fiber) delaying glucose absorption

None reported

Level II-1, C

*Potentially, but more research needed

Multiple Herb Combinations

Name

Mechanism of Action

Adverse Effects

Level of Evidence

Any Benefit?

Traditional Chinese Medicine

May decrease glucose absorption. Other mechanisms possible

None reported; diarrhea, vertigo, hypoglycemia case reported

Level I, C

Some may be of benefit, while others show no benefit. Studies need to be done more than once on standardized preparation

Native Herb Combination

Unclear

Minor GI discomfort

Level I

Current evidence  shows no benefit

Tibetan Medicine

Unclear

None reported

Level II-2, C

Inconclusive

Vitamins/Minerals/Other

Name

Mechanism of Action

Adverse Effects

Level of Evidence

Any Benefit?

Chromium

Component of glucose tolerance factor (GTF). Been shown to increase number of insulin receptors, enhance receptor binding, and potentiate insulin action

None reported

Level I, C

Potentially, but mixed results. More trials needed in North America.

Magnesium

Hypomagnesemia common in diabetes. Mg is co-factor in glucose oxidation, modulates glucose transport across cell membranes. May increase insulin secretion and/or improve insulin sensitivity/peripheral glucose uptake

None reported

Level I, C

Inconclusive due to mixed results

Vitamin E

Antioxidant capability which might influence protein glycation, lipid oxidation, and insulin secretion/sensitivity. May affect nonoxidative glucose metabolism

None reported

Level I, C

Inconclusive due to mixed results

Vanadium (Vanadyl sulfate)

Insulin-mimetic, up-regulates insulin receptors. Might enhance glucose oxidation/glycogen synthesis, and modulate hepatic glucose output

None reported

Level II-1, C

Suggestive, but RCTs needed

Alpha-Lipoic Acid

Antioxidant. May play a role in glucose oxidation. May increase glucose uptake in muscle, affect glycation, improve insulin sensitivity

None reported

Level II-3, C

Inconclusive; more research needed

L-Carnitine

Modulator of fuel substrate utilization in cells. Influences free fatty acid/glucose oxidation

None reported

Level I, A

Inconclusive; more research needed

Adapted from: Yeh, G..Y., Eisenberg, D.M., Kaptchuk, T.J., & Phillips, R.S. (2003). Systematic review of herbs and dietary supplements for glycemic control in diabetes. Diabetes Care, 26(4), 1277-1294.