Hoodia, The New Weight Loss Miracle?

Medical Author: Melissa Conrad Stoppler, MD
Medical Editor: William C. Shiel, Jr, MD, FACP, FACR
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The South African desert plant Hoodia gordonii, long ingested by Kalahari bushmen, has begun to attract widespread attention as a weight loss aid.

The only place in the world where Hoodia grows in the wild is the Kalahari desert in southern Africa. The plant has been eaten for centuries by the Kalahari bushmen living in the area, reportedly to prevent hunger during long journeys. A South African laboratory that had been studying indigenous plants for many years identified a molecule in the Hoodia plant, termed P57, that appears to suppress appetite. The South African researchers applied for a patent for the use of this compound as a diet aid and licensed it to a British pharmaceutical company, Phytopharm.

Scientists from Phytopharm say that the active ingredient in Hoodia, P57, acts on the brain in a manner similar to glucose and sends the message that you are full even when you have not eaten, thus decreasing your desire to eat. Ingestion of the Hoodia plant has no known reported side effects, although its taste is considered to be unpleasant and bitter.

According to CBS and BBC news reports, Phytopharm has spent millions of dollars in research on Hoodia and conducted a study of its effects on human volunteers. In their study, they report that obese volunteers who took Hoodia ended up eating about 1,000 calories per day less than those who did not take the supplement. But the pharmaceutical firm Phizer, which had teamed with Phytopharm and funded much of the research on Hoodia, dropped out of the project because of beliefs that it wouldn't be realistic to make pills out of the active ingredient in the Hoodia plant. Hoodia is grows in extremely hot conditions, and the plant takes years to reach maturity. Until now, the plant has never been cultivated and was only found in the wild. In order to increase its very limited supply, Phytopharm has established Hoodia plantations in South Africa, which are trying to establish cultivation and farming methods to grow the wild plant.

The BBC also reported in 2003 that it tested the "leading brand of Hoodia pills" sold in the U.S. and found no discernible evidence that the pills contained any active Hoodia. Because of the relative scarcity of Hoodia, the ingredient is hard for manufacturers to acquire, which makes it hard to understand how dozens of firms now claim to sell weight loss supplements containing Hoodia. Scientists at Phytopharm claim that many firms are fraudulently using their data and claims about Hoodia to market their own products. Phytopharm states that assays of "Hoodia" supplements from different companies show that these contain between 0.1 and 0.01 percent of the active ingredient claimed, according to a CBS report in 2004.

The study cited by the manufacturers of Hoodia certainly sounds intriguing. However, the study has not appeared in a peer-reviewed medical journal, so it is impossible to evaluate the quality of the study or its methodology. The FDA has warned manufacturers of products claiming to contain Hoodia that its effectiveness and safety have not been determined in humans. Likewise, both the Mayo Clinic and Dr. Andrew Weil have commented that there is of yet no conclusive evidence that Hoodia is a safe and effective appetite suppressant.

Right now, it's just too early to tell if Hoodia will revolutionize the diet industry. Double-blinded clinical trials are required to establish the safety and effectiveness of any product, and these have not yet been completed with Hoodia. Even those interested in trying Hoodia without waiting for clinical trials to be completed may have difficulties, since Phytopharm, the only licensed producer of Hoodia as a weight loss aid, does not yet market the product. Phytopharm's Web site states that "the necessary clinical trials and other studies to ensure the safety of the extract will take a few years before a product will be available." With reports of widespread counterfeit product, unless you have your supplements tested by an independent laboratory, it's hard to know if you are actually purchasing a product that truly contains the active ingredient.

For additional information, please visit the Weight Loss Center.

References: "Hoodia gordonii fact file." www.phytopharm.com. "African Plant May Help Fight Fat." CBS News, 11/21/05.

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