Mechanism of Action
The extract is said to curb appetite and reduce hunger, which works to decrease daily calorie intake. Another important ingredient found in this extract is hydroxycitric acid (HCA), which is thought to impart a weight reducing effect. The extract is also said to suppress the action of citrate lyase, an enzyme that is known to turn carbohydrates into fat and sugar. Blocking this enzyme actually promotes the reduction of fat.
Research
Research findings from animal studies have been encouraging and clearly indicate that garcinia cambogia extract may produce substantial weight loss. Studies conducted on rats indicate that the herbal extract could be beneficial in losing weight significantly. The studies suggest that the extract does act as a citrate lyase inhibitor (the enzyme which helps in the formation of fat cells). In some studies, there was an increase in serotonin synthesis, the brain chemical that controls appetite. Increase in serotonin puts a stop on cravings and reduces appetite.
Clinical Trials
When the extract was tested in clinical trials, one would have expected to see the same effect as observed in animal studies. However, the results of the studies conducted on human subjects were contradicting to the outcome noticed in animal studies. Although the studies on rats seem to prove the efficacy of garcinia cambogia, the contradictory findings observed in clinical trials puts a question on its use as a weight loss aid.
A study that was carried out for a period of 12 weeks and involved the participation of 135 individuals showed that garcinia cambogia extract was least effective in treating weight loss issues. In the study published in the Journal of the American Medical Association, subjects were divided into 2 groups. One group was put on a total dose of 3 g of garcinia cambogia extract, while the other group was given placebo treatment. The 3 g/day dose was divided into 3 doses, and taken 3 times a day before meals. Individuals in each group were advised to follow a high-fiber low-calorie diet during the study.
After the 12 week period, a loss of 7 pounds was noticed in the treatment group. On the other hand, adults in the placebo group were lighter by around 9 pounds. However, those taking the extract showed a body fat percentage (BFP) loss of around 1.6%, whereas, in the placebo group, there was a decrease of 2.6%. Comparing the results of body fat percentage and weight loss in both the groups, it was observed that the difference is small and could be ignored. In short, the final outcome of weight loss associated with garcinia cambogia is imperceptible, and cannot be considered as significant.
According to a 2004 systematic review reported in the American Journal of Clinical Nutrition that evaluated the results of meta-analyses and clinical trials conducted to test the efficacy of weight loss supplements (that included garcinia cambogia) at the University of Exeter and Plymouth, not even a single supplement was able to produce any weight loss effects.
In 2011, the Journal of Obesity reviewed data on 12 clinical trials conducted to examine the impact of garcinia cambogia as far as losing weight is concerned. The review pointed out to a mere 2 pound decrease in weight when the supplement was taken for several weeks.
Other studies that were conducted also showed that weight loss was insignificant, despite taking the extract for several weeks. In another study, subjects neither experienced any change in appetite nor in weight loss.
On the whole, there have been several studies that focused on the effectiveness of garcinia cambogia, but none of the findings were found to be consistent and conclusive. In most cases, weight loss results were small with hardly any clinical significance. Weight loss from this extract is a short-term side effect, and moreover, the magnitude of weight loss is negligible, despite taking it for an extended duration.
Although studies indicate it to be least effective, quite a few customer reviews have been positive. From the reviews, it appears that the supplement is a good product that requires you to follow no special diet or any rigorous exercise routine. The herbal extract is found to be safe, and as such there are no reports of any serious side effects. So, you can always give it a try, and who knows, it may work for you.
Disclaimer: The information provided in this article is solely for educating the reader. It is not intended to be a substitute for the advice of a medical expert.
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