Losing weight can be really hard. It takes discipline and sacrifice. That is why any shortcuts that can help people reach their weight and health goals are so highly sought-after.
The key is finding shortcuts that are effective in the short and long run, and, of course, that do not have any nasty side effects, which is often almost impossible to find in the supplements industry.
Frankly speaking, the supplements industry has some dirty secrets, and it’s not so easy to see through them. Last week I examined Green Coffee Bean Extract and in this article, I will go through some of the most important research conducted about Garcinia cambogia, a popular weight loss supplement.
Garcinia cambogia, also known as Garcinia gummi-gutta, Malabar tamarind, brindleberry, and kudam puli, is widely used as the newest and greatest natural weight-loss supplement. Read on to find out whether it could be an effective option to aid you in your weight-loss journey, or if it is just a waste of money.
What is Garcinia cambogia?
Garcinia cambogia is a tropical fruit native to Indonesia, used in Indian, Thai, Malaysian, and Burmese cuisine. It is yellow and light green in color, and resembles a small pumpkin. Traditionally, it is used to prepare sour curries, and it is also used as a purgative and a treatment for intestinal parasites in the Ayurvedic medical system (1). However, these uses are not the reasons Garcinia has gained so much attention worldwide.
Now, Garcinia cambogia extract is sold in weight loss clinics and through in-store and online supplement retailers, usually in pill-form, as the latest cure-all for your weight loss troubles.
Does Garcinia cambogia really work?
First, it is important to understand the claims as to how it helps promote weight loss.
How does Garcinia cambogia Work?
The substance found in Garcinia cambogia that has been claimed to have the potent weight loss effects is called hydroxycitric acid (HCA). The substance, found in the rind of the fruit, supposedly works towards weight loss in two ways: by blocking your body from making fat and by suppressing the appetite.
It seems that HCA blocks an enzyme called citrate lyase, which contributes to helping your body make fat. It also supposedly releases hormones that help to control cravings that can lead to weight gain.
It is important to note that Garcinia cambogia is not the only plant that contains HCA, however; Hibiscus, suvdariffa also contains significant amounts of HCA, but it has gotten much less attention in the weight-loss industry.
What does the research say?
There are several studies that have conflicting results.
The first studies carried out on the effects of Garcinia cambogia in the 1970s with obese rats demonstrated significant fat loss, with no effect on protein content (2).
Because there were flaws pointed out in the studies, like in the previous one, the first first adequately controlled trial carried out in 1999 to test the effectiveness of Garcinia cambogia and published in the Journal of the American Medical Association. It showed that Garcinia cambogia didn’t facilitate weight loss in rats (3). In this case, researchers even pointed out that the manufacturer’s preclinical research demonstrated that in order for Garcinia cambogia to work, it had to be administered with a simple carbohydrate-rich, low-fat diet.
More recent studies also carried out with rats have taken on different dimensions of the effects of Garcinia cambogia.
One study wanted to determine the effectiveness at high doses. Studies showed that even though Garcinia cambogia was effective at suppressing fat accumulation, rats experienced potent testicular atrophy and toxicity (4).
Another study wanted to determine if the weight loss effect of Garcinia cambogia was retained in the long-term, comparing two different diet compositions (1% fat and 12% fat), also in rats. They found that the long-term weight-loss effect was most effective in the group that had a 12% fat diet composition (5).
How about in humans?
The results in humans may not be so clear. One study carried out with eleven men divided the group of overweight individuals in two groups. One was given only HCA as a supplement, while the other was given HCA with medium-chain triglycerides. Both groups lost weight, but neither was more significant than the other (6).
Another small study carried out with seven men and fourteen women examined the effects of supplementation with HCA and combined HCA with medium-chain triglycerides (MCT) on a sense of fullness (satiety) in comparison with a placebo. After two weeks of supplementation, it was found that there was not an increase in satiety (7).
A larger study carried out with 135 subjects over a period of 12 weeks to demonstrate the effectiveness of Garcinia cambogia compared to a placebo. Both the people in the placebo group and those taking Garcinia cambogia lost weight, and the different was not significant. Thus, the study concluded that Garcinia cambogia failed to produce significant weight and fat loss beyond that observed with the placebo (8).
Not all studies produced negative results. One study wanted to see the influence of HCA on fat storage in situations with a high carbohydrate intake. They examined how 10 sedentary, lean males (one group who took HCA and another group who too placebo) stored fat when on a high-carbohydrate diet. It was found that the group that was supplemented with HCA stored less fat than the group that took the placebo. In addition, the HCA group had increased energy expenditure due to the desire to engage in more activities.
There are multiple studies that examine the effectiveness of HCA for weight-loss that give conflicting results, or positive results in specific conditions. In order to clear up some of the doubts, a meta-analysis was carried out that examined twelve clinical trials.
These trials compared the effectiveness of HCA over a placebo as a weight reduction agent. Nine of the twelve studies analyzed found a statistically significant difference in weight loss that favored HCA. However, in the groups that took HCA, gastrointestinal problems were twice as common as in the placebo group. The meta-analysis concluded that HCA can cause short-term weight loss, but pointed out that future, more rigorous trials need to be carried out in order for the results to be conclusive.
Were there any issues with the studies?
The meta-study pointed out a lot of the drawbacks or weak points of the studies previously mentioned. Some of these included:
- Poor taste of placebo in comparison to HCA.
- Small sample sizes, which may have influenced the results; without these trials, the results are no longer significant.
- Many of them left out some important statistical analyses.
- No information on the optimal dose of HCA; it seems to be currently unknown.
- It is unclear if the species of Garcinia (in addition to Garcinia cambogia, studies also used Garcinia atrovidris, and Garcinia indica) on the results.
- Seven of the studies did not specify the funding source.
- None of the studies indicated whether the outcome assessors were blinded.
- The relationship between HCA on weight loss while exercising is unclear.
Without a specialized eye, these factors are not easy to identify when reading the studies. However, when combined, they could have a profound effect on study results.
So, is it effective?
Studies show HCA found in Garcinia cambogia has a slight effect on weight loss. However, this is only effective in the short term, and the results of studies that test its effectiveness are no longer significant when only considering rigorous research design.
In order to be completely sure, it is important for studies to be more rigorous, longer, and the results have to be better reported.
What’s the verdict?
It seems to me that while the claims regarding Garcinia cambogia and HCA have some scientific backing, the effects aren’t what many claim them to be. Some of the price tags are very high, and they may cause some nasty side effects.
The supplement industry often looks for those studies that have positive results regarding HCA and weight loss, but they don’t necessarily look for the most rigorous studies, thus misleading buyers into thinking results are scientifically backed.
If you are looking to lose weight, make sure you have a solid diet and exercise routine in place first; if necessary, get guidance from a dietitian and personal trainer. A dietician will be able to help you identify what might be causing your weight gain (or “weight plateau”, for that matter), and help you take important actions to reach your goal. Continue on to our research into this year’s diet trends