If you watch Dr. Oz, you may have been exposed to a multitude of "health" products. He frequently advertises supplements and do-dads supposed to help you detox, get more energy, feel better, and/or lose weight. One specific product he has talked about that keeps coming up in my class is Garcinia cambogia, a supplement that is supposed to help with weight loss. Since I keep getting questions about it and I'm not an expert in it, I think it's time to take a look.
So my random questions of the day are:
What is Garcinia cambogia? Does it work, and is it safe?
Garcinia cambogia is a tropical fruit native to India. To me, it kind of looks like a cross between a melon and a gourd. Within this fruit is a chemical called hydroxycitric acid (HCA) which is supposed to help with weight loss by inhibiting appetite and reducing fat synthesis. Let's look at the research to see if it really does what Dr. Oz says it does.
When it comes to supplements and medications, it is important to look at the research. While a product may work, it often times is contingent on certain criteria such as age and health status of the users, diet, how much they take, how long they take it for, other products being taken, etc. With this product it looks like there is a lot contradicting information when it comes to dosage, duration, and efficacy.
For instance, in a small study, at 1200 mg per day, HCA did not appear to be helping reduce appetite or increase weight loss. (Mattes and Bormann, 2000). A different small study showed that 1500 mg per day of HCA helped patients lose almost 3 pounds more than the placebo in 12 weeks (Mattes and Bormann, 2000). And another small study showed that 1000 mg of HCA per day was effective at reducing visceral (tummy) fat (Hayamizu et al., 2003). Those are some confusing results.
Luckily, I was able to find a good meta-analysis study that sums up all of the research on this stuff up until 2010. The dosage and duration of the studies seem to be all over the place, ranging from 1000-2800 mg per day for anywhere between 2 and 12 weeks. According to this article, some studies say it works, and other studies say it doesn't. Unfortunately, almost all of the research published on HCA has "systematic
issues" like small sample sizes that weren't statistically checked
and/or non-compliant participants that weren't accounted for properly. Also, some side effects were reported - headache, nausea, GI issues, and/or respiratory problems.(Onakpoya et al., 2010)
Because all of the research seems to be done in poorly designed, small studies and the results are somewhat conflicting, neither the American Society of Clinical Nutrition nor the American Academy of Family Physicians recommend taking HCA for weight loss.
Furthermore, the Food and Drug Administration (FDA) only approves one over-the-counter supplement for weight loss - Alli. That means all of the other supplements either do not work or are not safe. For instance, Hydroxycut (which contained HCA by the way) has very strong warnings from the FDA. They say to immediately stop using Hydroxycut products due to serious health effects related to liver injury (Warning on Hydroxycut Products, 2009). In my opinion, the FDA is not really all that strict, so if they don't like it, I definitely don't like it.
Honestly, I'm not surprised with what I found. Most research on supplements are inconclusive. That's why they're supplements and not patented medications. If a product is proven to work, it is probably going to be a medication, not a supplement. Also, if Dr. Oz advertises it, I don't trust it. How do you think it got on his show? - $$$$$. In my opinion, every product on that show has an immediate conflict of interest. He drives me nuts, and I'm not afraid to admit it :)
