BACKGROUND: Extracts from Hoodia gordonii have been shown to decrease food intakes and body weights in animals and were proposed as a food supplement or ingredient for weight management.
OBJECTIVE: We assessed the safety and efficacy of a 15-d repeated consumption of H. gordonii purified extract (HgPE) relative to a placebo in humans.
DESIGN: Healthy, overweight women, who were stratified by percentage body fat, received either HgPE (n = 25) or a placebo (n = 24) for 15 d. Subjects were resident in a clinic for a 4-d run-in period and a 15-d treatment period in which they received 2 servings/d of 1110 mg HgPE or a placebo formulated in a yogurt drink 1 h before breakfast and dinner. Subjects were otherwise allowed to eat ad libitum from standardized menus.
RESULTS: There were no serious adverse events, but HgPE was less well tolerated than was the placebo because of episodes of nausea, emesis, and disturbances of skin sensation. Blood pressure, pulse, heart rate, bilirubin, and alkaline phosphatase showed significant (P < 0.05) increases in the HgPE group. Mean effects on ad libitum energy intakes and body weights did not differ significantly between the HgPE- and placebo-treatment groups (P > 0.05).
CONCLUSIONS: In comparison with a matched placebo, the consumption of HgPE for 15 d appeared to be associated with significant adverse changes in some vital signs and laboratory parameters. HgPE was less well tolerated than was the placebo and did not show any significant effects on energy intakes or body weights relative to the placebo. This trial was registered at clinicaltrials.gov as NCT01306422.

Hoodia gordonii is a spiny succulent plant popularly consumed for its purported anti-obesity effect. Traditionally used by the Khoi-San of South Africa and Namibia as a hunger and thirst suppressant while on long hunting trips, the commercialisation of this plant has been highly controversial due to intellectual property rights and benefit sharing issues, as well as the fact that several prominent pharmaceutical companies involved in its development have withdrawn their interest. Quality control has been the main focus of scientific studies as the supply of H. gordonii plant material is limited due to its sparse geographical distribution, slow maturation rate, need for a permit to cultivate or export material as well as high public demand, contributing to adulteration of a large amount of products. Despite the isolation of numerous steroidal glycosides from H. gordonii, the main focus has been on the pregnane glycoside P57, considered to be the active ingredient and marker molecule to determine quality of raw material and products. Publications based on scientific studies of key aspects such as in vivo biopharmaceutics, the biological activity of all chemical constituents, clinical efficacy, and especially safety are insufficient or completely absent causing great concern as H. gordonii is one of the most widely consumed anti-obesity products of natural origin. This review offers an up-to-date overview of all the current available knowledge pertaining to H. gordonii achieved by systematic analysis of the available literature.

* * * * * * * * * * * * * * * * * * *

Whelan AM, Jurgens TM, Szeto V. Case report. Efficacy of Hoodia for weight loss: is there evidence to support the efficacy claims? J Clin Pharm Ther. 2010 Oct;35(5):609-12. doi: 10.1111/j.1365-2710.2009.01116.x. PubMed PMID: 20831685.

Increasing rates of adult obesity and its negative health consequences are likely to become an increasing burden to the Canadian health care system. Consumers are looking for treatment options and often try the natural health products that are heavily promoted as safe, fast and effective. In this case report, MH, a 57-year-old overweight female wanted advice regarding whether she should use the natural product Hoodia to help her attain her weight loss goals. A literature search was conducted using Medline, EMBASE, the Cochrane Library, Natural Medicines Comprehensive Database and IPA from inception to March 2009. The internet, files of the authors and bibliographies of articles were searched for additional references. No published, peer-reviewed randomized controlled trials examining efficacy of Hoodia were found. Unpublished data from two small trials reported promising results with no adverse events. However, this leaves many unanswered questions regarding the use of Hoodia for weight loss such as the appropriate dose and duration, short and long term safety and use in patients with concomitant diseases. Literature suggests that some commercial products may not actually contain Hoodia at all. Additionally, Hoodia is not yet listed in the Canadian Licensed Natural Health Products Database meaning products sold in Canada may not meet Canadian regulatory standards. Upon discussing this information, MH decided not to use Hoodia, and other evidence-based recommendations were discussed.