The hydroxycitric acid found in garcinia cambogia has been shown in test tubes and animals to inhibit an enzyme called citrate lyase and interfere with fatty acid metabolism in scientific studies, according to Consumer Reports. Some weight-loss supplement manufacturers use these scientific findings to claim that products containing garcinia cambogia can slow a human body's ability to absorb fat and decrease appetite.
Garcinia cambogia, also called the Malabar tamarind, is a fruit that grows in Southeast Asia. This small, purple fruit is the primary natural source of hydroxycitric acid, which is a derivative of citric acid. According to a fact sheet published in 2014 by NYU Langone Medical Center, HCA has been found to have positive effects on metabolism in preliminary studies. However, clinical trials on humans have produced mixed results and no definitive conclusions that support the weight-loss claims of supplements containing garcinia cambogia and HCA. Positive weight-loss and fat-burning effects have only been observable in the short term without long-term substantiation.
A typical dose of HCA is 250 to 1,000 milligrams three times each day. As of 2014, an article in Critical Reviews in Food Science and Nutrition notes that no serious side effects have been reported in healthy adults as a result of taking supplements that use either the fruit extract or the chemical concentration within this dosage range.