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HOODIA
What is Hoodia? | Active ingredient | Scientific evidence | Media release | Anecdotal evidence
What is Hoodia?
Hoodia, also known as Xhoba, is a succulent that looks like a cactus. It has been described as a somewhat bitter-tasting cucumber that
thrives in extremely hot, dry weather and takes 5-7 years to reach maturity. Hoodia grows to a height of about 40cm in the Kalahari Desert region of South
Africa, as well as the countries of Botswana, Namibia and Angola.
It is said that for generations the San Bushmen, tribesmen native to the regions Hoodia grows, used Hoodia Gordonii to control appetite in lean times. They
removed the skin and spines of Hoodia prior to consumption as a way to curb their hunger and thirst during nomadic hunting trips.1
For more detailed information, including scientific names, see here.
What is Hoodia? | Active ingredient | Scientific evidence | Media release | Anecdotal evidence
Active ingredient
In 1977, the South African Council for Scientific and Industrial Research (CSIR) isolated the ingredient in hoodia—now known as P57—which is responsible for
its appetite-suppressant effect, and patented it in 1996.2
Dr Richard Dixey, who works for the first marketer of Hoodia based weight control products, explained how P.57 actually works: "There is a part of your
brain, the hypothalamus. Within that mid-brain there are nerve cells that sense glucose sugar. When you eat, blood sugar goes up because of the food, these
cells start firing and now you are full.
What the Hoodia seems to contain is a molecule that is about 10,000 times as active as glucose. It goes to the mid-brain and actually makes those nerve cells
fire as if you were full. But you have not eaten. Nor do you want to."3
What is Hoodia? | Active ingredient | Scientific evidence | Media release | Anecdotal evidence
Scientific evidence
The internet describes successful tests for the effectiveness of Hoodia as an appetite suppressant on some sites and laments the lack of
scientific evidence on others.
Dr R. Dixey organised the first animal trials for Hoodia. Rats, a species that will eat literally anything, stopped eating completely. When the first human
clinical trial was conducted, a morbidly obese group of people were placed in a "phase 1 unit", a place as close to prison as it gets. All the volunteers
could do all day was read papers, watch television, and eat. Half were given Hoodia, half placebo. Fifteen days later, the Hoodia group had reduced their
calorie intake by 1000 a day. It was a stunning success.4
Wikipedia presents the following additional information, used here as a summary of all the argument for and against the efficacy of Hoodia as an appetite
suppressant.5
Animal research on hoodia includes just one published scientific study in which a purified extract of Hoodia Gordonii, known as P57, was injected directly
into the brains of rats.6 The author of the rat study said that P57 was easily broken down by the liver, so it might be
hard to take in enough of it to ensure that it had an effect. MacLean cautioned that currently available supplements might be inadequate, stating "I
question whether there is really enough of the active ingredient in there to do much."7
Richard M. Goldfarb, MD, a doctor and medical director of Bucks County Clinical Research in Morrisville, Pennsylvania, claims to have conducted a preliminary
efficacy study of Hoodia gordonii on seven people and reports to have found it effective. This very small trial was reportedly sponsored by a Hoodia
manufacturer and none of the findings were ever published in any peer-reviewed journal. Such information cannot be considered as evidence that hoodia is
effective as a weight loss product.8
 Other medical weight loss experts remain skeptical and do not recommend hoodia to obese patients. Adrienne Youdim, MD, medical director of the Comprehensive
Weight Loss Program at Cedars-Sinai Medical Center and Michael Steelman, MD, chairman of the board of trustees for the American Society of Bariatric
Physicians says "There is no [published scientific] data to support its use."9 In addition, the FTC recommends against the
use of such diet products marketed with exaggerated claims.10
What is Hoodia? | Active ingredient | Scientific evidence | Media release | Anecdotal evidence
Media releases
In May 2003, BBC correspondent Tom Mangold filed a story on Hoodia that started the media hype in the Western World. The BBC site for this article is
here. If this link does not work an archive copy of the article
can be found here. Tom’s story led CBS’ 60 Minutes to pick up on the interest in November 2004. Their story, and the
video link, are found here. If this link does not work an
archive copy of the printed article can be found here.
What is Hoodia? | Active ingredient | Scientific evidence | Media release | Anecdotal evidence
Anecdotal evidence
Example 1
John -- who asked not to be identified by his real name -- swears by hoodia. Until recently, the 53-year-old grocery store employee in Nova Scotia weighed
345 lb. After some online searching, he bought 60 capsules for $55. Three weeks after taking one pill in the morning and another at night, he had lost 20 lb.
John, however, coupled his hoodia intake with the low-carb Atkins diet. "I've eaten my two small meals -- in the morning and at suppertime -- and that's it,"
says John. But how does he know it's the pills? "I've dieted many times," says John. "I know myself and I'm always hungry. If you can't lose weight with
hoodia, it's not likely you will ever lose it -- it's really that good."11
Example 2
In order to see for ourselves, we drove into the desert, four hours north of Capetown in search of the cactus. Once there, we found an unattractive plant
which sprouts about 10 tentacles, and is the size of a long cucumber. Each tentacle is covered in spikes which need to be carefully peeled. Inside is a
slightly unpleasant-tasting, fleshy plant.
At about 1800hrs I ate about half a banana size - and later so did my cameraman. Soon after, we began the four hour drive back to Capetown.
The plant is said to have a feel-good almost aphrodisiac quality, and I have to say, we felt good.
But more significantly, we did not even think about food. Our brains really were telling us we were full. It was a magnificent deception. Dinner time came
and went. We reached our hotel at about midnight and went to bed without food. And the next day, neither of us wanted nor ate breakfast.
I ate lunch but without appetite and very little pleasure. Partial then full appetite returned slowly after 24 hours.12
References
- http://consumerhealthdigest.com/hoodia_hype.htm?source=hoodiawords accessed 15 April 2008
(return to article)
- Dixon, Robyn (December 26, 2006). Hoodia fever takes a toll on rare plant. Los Angeles Times. (return to article)
- Mangold, Tom - http://news.bbc.co.uk/1/hi/programmes/correspondent/ 2947810.stm accessed 10 April 2008 (return to article)
- Ibid (return to article)
- http://en.wikipedia.org/wiki/Hoodia_gordonii accessed 11 April 2008 (return to article)
- MacLean D. and Luo L. (2004) Increased ATP content/production in the hypothalamus may be a signal for energy-sensing of satiety: studies of the anorectic mechanism of a plant steroidal glycoside. Brain Research. 2004 Sep 10;1020(1–2):1–11. (return to article)
- Duenwald, Mary (April 19, 2005) "An Appetite Killer for a Killer Appetite? Not Yet." The New York Times. (return to article)
- Kathleen Doheney, "Hoodia: Lots of Hoopla, Little Science; Few studies support the promise of the South African appetite suppressant, but believers abound", WebMD, September 6, 2006, Reviewed by Louise Chang, MD (last accessed March 24, 2007). (return to article)
- Ibid (return to article)
- Weighing the Evidence in Diet Ads, US Federal Trade Commission (return to article)
- Danylo Hawaleshka http://www.macleans.ca/science/health/article.jsp? content=20050801_110122_110122 accessed 15 April 2008. This article also contains comment from someone who feels Hoodia did NOT work for her. (return to article)
- Mangold, Tom - http://news.bbc.co.uk/1/hi/programmes/correspondent/ 2947810.stm accessed 4 April 2008 (return to article)
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