Garcinia cambogia is a fruit grown across India and Southeast Asia and it is used there as a food and its rinds are used in some traditional recipes of south India.
It used to be an obscure hard-to-find ingredient, but recently the Internet has exploded with websites selling weight loss products based on an extract of the fruit and it even got some decidedly hucksterish treatment from Dr. Oz, a TV personality made famous by Oprah Winfrey.
The fruit is known in India as gambooge. It is apparently also an ingredient in some weight loss products as hydroxycitric acid. Dr. Oz promoted it and continues to assert that garcinia cambogia is an effective aid to weight loss. The claims for weight loss are nothing short of outlandish and there is real science that suggests the whole thing is a hoax.
Studies that claim to have found weight loss were carried out on animals. Studies involving humans are for the most part badly designed.
A few quality studies have been carried out over the years, starting in 1998 with a double-blind, placebo-controlled trial of 135 adults over 12 weeks published in The Journal of the American Medical Association. They found no evidence that hydroxycitric acid, the active ingredient in weight loss products made from garcinia cambogia, produced significant weight loss.
The American Journal of Clinical Nutrition in 2004 published a systematic review of meta-analyses and clinical trials on dietary supplements for weight loss by complementary medicine researchers at the Universities of Exeter and Plymouth. None of the over-the-counter weight loss aids worked, including garcinia cambogia.
Late in 2010 the peer-reviewed Journal of Obesity published a meta-analysis of studies testing the garcinia as a weight loss aid. Of the 23 trials they identified, 12 were methodologically sound enough to include in their analysis.
The analysis revealed that some statistically significant weight loss occurred, but “the magnitude of the effect is small and the clinical relevance is uncertain.” They also found that gastrointestinal adverse events were twice as likely in the hydroxycitric acid group as in the placebo group.
When you are considering the potential benefits of products look for meta-analysis studies that take in all the sound research available. One-off studies that get a significant result are not evidence of anything. Only when an effect is repeated in many studies by many scientists should you believe.
RANDY SHORE‘s new cookbook Grow What You Eat, Eat What You Grow is now available at Chapters, Book Warehouse, Barbara-Jo’s Books to Cooks and Whole Foods.
LISTEN TO THE GREEN MAN PODCAST
The Green Man Podcast is not just a broadcast version of the Green Man Blog: It’s much, much more. For the past seven weeks I have been creating a weekly broadcast with interesting, opinionated and sometimes controversial guests.
To view the entire catalogue including notes on the shows and the guests – and multimedia audio player – click here. You’ll find podcasts on the modern revival of hunting for sustainable meat, the real value of organic foods, the benefits and risks of raw milk, urban farming, craft beer and the ethics of eating meat.
Here is a sample and audio players so you can enjoy the broadcasts right now on your computer. Search “Randy Shore” on iTunes to download to your smartphone or tablet.
The Paleo Diet
Host Randy Shore welcomes paleo nutritionist Travis Steward and St. Paul’s Hospital dietitian Sinead Feeney for a paleo diet cage match. Should you eat like a caveman? Should you eat like Alton Brown? How about eating like the Green Man, Randy Shore?
Ethical Killing and Sustainable Hunting
Host Randy Shore, Harrison Mooney and hunting instructor Dylan Eyers of EatWild.ca talk about the modern revival of hunting in B.C. Urbanites, hipsters, hippies and women are taking up hunting as a way to harvest ethical, sustainable meat and reject the industrial food industry.
Animal Welfare and the Ethics of Meat
Host Randy Shore, Vancouver Sun reporter Zoe McKnight and Leanne McConnachie of the Vancouver Humane Society talk about the ethics of meat, the reality of industrial farming and animal welfare. Omnivore Shore – a recovered vegetarian – takes on two practicing vegetarians over who should eat what and why.
The Benefits and Risks of Raw Milk
Host Randy Shore welcomes raw milk activist Jackie Ingram and farmer Alice Jongerden of Home on the Range Dairy. Do the health benefits of raw milk outweigh the potential risks? Are the benefits proven? What about the risks?
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