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Hoodia and weight loss … it can all be summed up with the word Caution


Melissa Divack

Health Psychology

Professor Schlundt


What is Hoodia and where does it come from?

            With the diet craze that is going on in the United States today, when something new pops up we jump on it.  Hoodia is one of those very things.  Although it has just been brought to our attention recently, it has been used by the San Bushmen in South Africa for many, many years.  Although there are many different types, authentic Hoodia, also known as Hoodia gordonii, is one of the rarest botanicals in the world and is the only variety believed to have the appetite suppressant in it.  Although many think it’s a cactus, since it has a spiny appearance and looks like one, it is actually a succulent.  Hoodia gordonii is so rare because it takes somewhere around 5 years for the plant to mature before it can be harvested and used and must be grown in extremely hot environments, like the Kalahari Desert in South Africa.  The San Bushmen would eat the Hoodia before going on long hunting trips so that it would suppress their appetite and diminish their thirst, and some claim that it can boost energy as well.  They believed it had some medical purposes as well, such as helping “severe abdominal cramps, hemorrhoids, ingestion, hypertension and diabetes” (  


How does it work?

            Just like other weight loss remedies Hoodia gordonii claims to be an appetite suppressant, but how exactly does it work?  Once word of Hoodia got out, South African scientists wanted to figure out what made it effective.  They teamed up with Phytopharm and found that the active ingredient was a steroidal glycoside, P57AS3, which is now known as P57 (J AOAC, 2006).  The P57 molecule has a very powerful effect on the brain, especially the hypothalamus.  This “miracle molecule” fools the brain into thinking that the person is full, and this feeling can last for a full 24 hour period ( 


What’s being said about the effectiveness of Hoodia, what is the evidence and who is saying it?

            There have many good things said about Hoodia and many claims made to its effectiveness.  According to research done on P57, “it appears to have novel pharmacological properties and may in fact be the first ever true appetite suppressant to be discovered … and has no effects on behavior” ( 

            There have also been several popular broadcasts about how it works, including 60 minutes, ABC, BBC, and even Oprah Winfrey had an article about it in her “O” magazine.  Leslie Stahl, reporter for 60 minutes, and her crew went to South Africa to try out Hoodia for themselves.  She said that “she lost the desire to eat or drink for the entire day.  She also didn’t experience any immediate side effects, such as indigestion or heart palpitations” (  On the other hand, BBC put out a report in 2003 saying that there was no real evidence that Hoodia pills contained any active Hoodia.  They said, “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 (  Also, according to the Phytopharm scientists, there are a lot of firms who are fraudulently using data and claims that they have patented about Hoodia to market other products.  The other companies and firms are putting barely any Hoodia in their products, yet claim it is pure and 100% natural, which it obviously is not. 

            There are many claims out there, good and bad, but only a few talk about health issues other than weight loss and prevention of obesity.  An example of such a claim is, “Being overweight is often associated with high blood pressure, high blood cholesterol, and insulin resistance.  This is the metabolic Syndrome X, which affects 70 million Americans and is a common cause of premature death and or disability.  Hoodia could be an important nutritional factor to combat Syndrome X, if it fulfills its promise of appetite control and weight loss” ( 


Clinical Trials that have been done

            Although there haven’t been many clinical trials, the ones that have been done have shown to be in favor of Hoodia and how it works as an appetite suppressant.  Phytopharm is the firm that obtained the rights to use and work with P57, the working molecule in Hoodia.  Starting in 2001, Phytopharm started their two phase clinical trial on the effects of P57 on individuals.  Sixty two healthy males were picked to volunteer in the first phase, which had three stages.  “The first stage evaluated the safety, tolerability and pharmacokinetics of ascending single doses of the product.  The second stage assessed the effects of repeated dosing, in healthy overweight volunteers.”  Then, after phase one was completed, they had plans to continue on to phase two.  “In the Phase IIa trial obese subjects will be given P57 over a ten-day period to demonstrate efficacy in reducing caloric intake” (  There have been a few other clinical trials done, but they have been performed on rats.  Because the brains of rats and humans vary greatly, I don’t feel as though we can use these studies as significant evidence about how it can affect humans. 


Some important precautions

            According to Cathy Wong, N.D., people who have diabetes and who are looking to use Hoodia should be very cautious.  “Because Hoodia tricks the brain into thinking it has enough blood sugar, it’s possible that a person’s blood sugar could drop dangerously low while taking Hoodia.  With regular hunger mechanism turned off, the normal warning signs may be suppressed – until it’s too late” (  Another thing that they are very worried about is the product being used or abused by individuals with eating disorders. 

            There have already been public comments made about how dangerous the use of Hoodia can be in an extreme dieter with an eating disorder.  There has even been a proposed warning for the use of Hoodia gordonii as a dietary supplement.  It reads, ‘Not to be used in childhood, pregnancy or lactating females who are breastfeeding.  Not to be used by individuals with eating disorders or those who are underweight or within a normal weight range.  Allergic reactions may occur, as with all plant material.  Reduced calorie intake can affect the control of diabetes mellitus.  In cases of doubt, check with a medical practitioner prior to use” ( 



            Since Hoodia gordonii is a relatively new development here, there isn’t much scientific evidence or clinical trials that have been done on humans.  The majority of the testimonials out there are personal “success” stories or claims from websites who are trying to sell weight loss pills.  After a lot of researching and what we already know, it is clear that we cannot just trust what we see or read.  If you are looking for the real thing, a product actually containing Hoodia gordonii, you will need to know about and look for certification.  In order to put the “real” stuff on the market, they need to obtain a C.I.T.E.S. certificate, which obtained after the material and tested.  You can take a look and get a better idea of what I am talking about at

            It is also important to remember that diet pills and weight loss plans don’t work for everyone the same way, and may not even work at all.  Even after reading all of the positive claims and evidence, I am still skeptical of the product at hand.  There are many different kinds, and like a million different pills and liquids out there claiming that they are “the real thing” and some even have fake certificates on the bottles.  I have always been skeptical of weight loss and diet pills and after reading the information, my fears have been confirmed.  The pills being taken by tons of people out there are being filled with false hope and who knows what is actually in those pills.  I do think that if I had the chance to try the real Hoodia gordonii, I would try it to see for myself if it worked.  The best word to describe how to go about picking and using weight loss and diet pills is caution




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