As Jack Handey of “Deep Thoughts” fame on SNL once said, “Broken promises don’t upset me. I just think, why did they believe me?”
Looks like he is at it again! Introducing the newest “revolutionary fat buster” supplement guaranteed to help you lose weight and endorsed by none other than Dr. Oz: Garcinia cambogia.
So, is this just another in a long line of hyped-for-no-reason weight loss supplements? Or is this really “the magic ingredient that let’s you lose weight without diet or exercise” [emphasis ours]? Sorry to disappoint, but the search for the weight loss magic bullet continues, because this ain’t it!
The Garcinia cambogia fruit, a relative of tamarind, is a small pumpkin-resembling fruit native to Southeast Asia, coastal India and parts Africa (1). Traditionally used in curries and to preserve fish, extracts from the rind of this tropical fruit are now being touted as the “newest, fastest fat buster”. But, once again, is there any evidence? Dr. Oz claims in the TV spot above there is “revolutionary new research” showing Garcinia cambogia as a miracle weight loss agent… but we sure couldn’t find anything revolutionary!
How is it supposed to work?
Dried Garcinia cambogia contains up to 30% citric acid, most in a form called hydroxycitric acid (HCA), which was discovered in 1970 and is thought to be the active compound linked to weight loss (1). That’s why HCA derived from Garcinia cambogia has been an ingredient in weight loss supplements for ages, including the supplement it’s named after – Hydroxycut (yes, that Hydroxycut!). The way HCA is *thought* to help with weight loss is by:
- reducing the amount of fat and cholesterol your body makes
- altering the release of serotonin and leptin, which affect your appetite
- reducing circulating insulin, which influences fat storage
What’s the evidence?
As always, there are some promising animal studies. A Garcinia cambogia-containing diet preparation called Rapha® was pretty successful in mice. In addition to Garcinia cambogia, Rapha® also contains a mishmash of other buzz-worthy ingredients such as silkworm pupa peptide (yum!) and extracts of white bean, raspberry, mango, cocoa and green tea. That’s what we like to call everything-but-the-kitchen-sink! While this Rapha® diet reduced weight gain and cholesterol levels when mice were fed a high-fat diet (2), who says Garcinia cambogia had anything to do with it?
There are other animal studies with positive weight loss results, but let’s get to the big question – what about studies with people? There are not that many! When 86 overweight individuals were randomized to Garcinia cambogia extract, Glycine max extract (another magic bullet) or placebo NOTHING happened when they continued eating their usual diet. NOTHING – no weight loss, clinically significant change in body fat, no decrease in cholesterol (3). Hmmmmm. A recent review paper has summarized the evidence for Garcinia cambogia and weight loss from 15 clinical studies (1). Their conclusion?
“…there is still little evidence to support the potential effectiveness and long-term benefits of G. cambogia extracts.”
No Baloney’s advice? Is this the “Holy Grail” of weight loss? If it was, we would have known by now… HCA, the purported active compound from Garcinia cambogia was an ingredient in Hydroxycut for YEARS (so was ephedra). That is, before they removed HCA from the Hydroxycut formulation for safety reasons. When cases of liver failure and death related to Hydroxycut were reported (4), the manufacturer’s removed Garcinia cambogia when the FDA advised consumers to avoid the supplement (5).
So, if a major supplement brand has already removed it from their product and some experts are calling for more stringent safety precautions, remind me again why taking Garcinia cambogia for weight loss is a good idea? While there are several studies that have found no adverse effects with Garcinia cambogia even WebMD only lists it as “POSSIBLY SAFE” for most people. Maybe we will eat our words one day, but today is not that day! Thanks, but no thanks; we’ll stick with diet and exercise.
- Márquez F, et al. Evaluation of the safety and efficacy of hydroxycitric acid or Garcinia cambogia extracts in humans. Crit Rev Food Sci Nutr 2012; 52:585-94.
- Kim J, et al. Anti-obesity effects of Rapha diet® preparation in mice fed a high-fat diet. Lab Anim Res 2012; 28:265-71.
- Kim JE, et al. Does Glycine max leaves or Garcinia Cambogia promote weight-loss or lower plasma cholesterol in overweight individuals: a randomized control trial. Nutr J 2011; 10:94.
- Dara L, Hewett J, Lim JK. Hydroxycut hepatotoxicity: A case series and review of liver toxicity from herbal weight loss supplements. World J Gastroenterol 2008; 14: 6999-7004.
- Lobb A. Hepatoxicity associated with weight-loss supplements: a case for better post-marketing surveillance. World J Gastroenterol 2009; 15:1786-7.