His original study, conducted by Columbia University’s Obesity Research Center, looked at 135 overweight men and women age 18 to 65; about half were given garcinia cambogia and the other half a placebo three times a day before meals. Both groups ate a high-fiber diet and returned for evaluation every two weeks. At the end of the 12-week trial, there were no important differences in weight loss between the two groups.
A review of 12 trials involving garcinia products published in the Journal of Obesity in 2011 came to the same conclusion. Another study by researchers at Victoria University in Melbourne, Australia, and published in 2013 in the journal Complementary Therapies in Medicine found that overall the evidence for garcinia cambogia was “not compelling.”
As for garcinia cambogia's side effects, controlled studies and animal studies have found very few, although Heymsfield says, “I don’t think it’s 100 percent safe.”
In 2009 the Food and Drug Administration warned consumers about Hydroxycut, a product line containing garcinia cambogia and several other ingredients, based on serious reports of health problems, including jaundice, elevated liver enzymes, liver damage requiring a transplant, and one death from liver failure. The FDA said it was unable to determine exactly which ingredients were associated with the liver injuries. (Hydroxycut's manufacturer, Iovate Health Sciences, withdrew the products, though it has since returned a reformulated product to the market containing no garcinia cambogia.)
“Being obese is difficult because only some of it is related to self-control,” Heymsfield says. “And it’s not easy to lose weight in our environment. Just preventing further weight gain is an accomplishment for some people.” The biggest problem with garcinia cambogia, Heymsfield says, besides being a waste of money, is that it distracts people from concentrating on the important things when it comes to weight loss: increasing your activity level and eating a healthier diet.
As for my mom, she returned the bottle to Costco and got her $20 back.