Herbs - A Safe and Effective Way to Lose Weight?

A variety of products are sold in stores as natural weight loss aids, most of which have not been scientifically evaluated. Seven percent of Americans are using over the counter weight loss products, and most are young women.


Because of the Dietary Supplement and Health Education Act (DSHEA) passed by Congress in 1994, weight loss and other supplements are not regulated by the FDA, are not required to demonstrate efficacy for the conditions for which they are promoted, and are not even required to prove that they contain what they claim to contain.


Many of the supplements currently promoted for weight loss have sympathomimetic effects; in other words they are compounds from plants, herbs, or other natural compounds that stimulate the sympathetic nervous system. They carry the same risks as prescription drugs that stimulate the sympathetic nervous system.


One such supplement is the Chinese plant Ma Huang, which contains ephedra, a compound similar to ephedrine, which stimulates the sympathetic nervous system. Ephedra increases heart rate, blood pressure and energy expenditure, stimulating ²-1 and ²-2 adrenergic sympathetic receptors. Ephedra is often combined with caffeine as a weight loss supplement. Ma Huang is also combined with guarana, a Brazilian plant with a high caffeine concentration, and promoted as a weight loss supplement. A recent meta-analysis that pooled the results from several different studies together showed that ephedra containing products result in weight loss of 2 pounds per month, although no information is available for treatment longer than 6 months.

Ephedra is one of the most dangerous over the counter supplements available today. It accounts for the majority of all reports of adverse events for herbs and supplements to the FDA. It is associated with a 2-3 fold increase in psychiatric, autonomic, heart related and gastrointestinal side effects. 87 episodes of heart attack, stroke, seizures, and high blood pressure have been reported to the FDA. It has been associated with several deaths, including a pitcher for the Baltimore Orioles, which led to the unusual (for a supplement) step of the FDA banning it in 1994. The FDA has since revoked the ban.

Hydroxycitric acid is sold under the name garcinia and is promoted for weight loss. It has been shown to inhibit the enzymes that convert compounds into coenzyme A, blocking the storage of energy as fat. The evidence related to its ability to promote weight loss is contradictory. Other products, including psyllium, guar gum, chitosan, chromium, and conjugated linoleic acid showed no effect on weight loss, although they have no major potential toxicities.

The bottom line is that the only natural herbs that might help you lose weight (i.e. Ma Huang) also carries significant potential risk that may be as great as prescription drugs. Sustained changes in diet and exercise that are adopted for life are the best way to lose weight and keep it off.