You may see ads for supplements that claim they will help you lose weight. But many of these claims are not true, and some of these supplements can have serious side effects.
A special note for women: Pregnant or nursing women should never take diet medicines of any kind. This includes prescription, herbal, and other over-the-counter remedies. Over-the-counter refers to drugs or supplements you can buy without a prescription.
Herbal Remedies, Supplements, and Other Weight-loss Products
There are many over-the-counter diet products. These include a number of herbal remedies. About 7% of American adults use nonprescription weight-loss products.
Most of these products do not work, and some can be dangerous. Before using an over-the-counter or herbal diet remedy, talk with your health care provider.
Nearly all of the current over-the-counter supplements with claims of weight loss contain some combination of these ingredients:
EPA-rich fish oil
There is no proof that these products help with weight loss.
Safety of Over-the-Counter Diet Products
Some ingredients in over-the-counter diet products may not be safe. The Food and Drug Administration (FDA) warns people not to use some of them. Do not use products that contain these ingredients:
Ephedrine is the main active ingredient of herbal ephedra, also known as ma huang. The FDA does not allow the sale of drugs that contain ephedrine or ephedra. Ephedra can cause serious side effects, including strokes and heart attacks.
"Brazilian diet pill," also known as Sim and Herbathin dietary supplements. The FDA has warned consumers not to buy these products.
Conjugated linoleic acid (CLA) is found in many dietary products (such as Biosculpt Liquid, Body Success, and GNC Optibolic Body Answers Dietary Formula). There are several possible worrisome side effects.
Products containing tiratricol, also known as triiodothyroacetic acid or TRIAC. These contain a thyroid hormone, and they may increase the risk for thyroid disorders, heart attacks, and strokes.
Fiber supplements that contain guar gum. These have caused blockages in the esophagus (the tube that carries food from your mouth to your stomach) and intestines.
Chitosan. This is a dietary fiber from shellfish. Some products that contain it are Natrol, Chroma Slim, and Enforma. People who are allergic to shellfish should not take these supplements.
Remedies that list the ingredient plantain. These may contain digitalis, a chemical that affects the heart. NOTE: This plantain is not the harmless banana-like fruit that is also called plantain.
David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.