Garcinia cambogia is a popular weight loss supplement.
It is extracted from a tropical fruit of the same name, also known as the Malabar tamarind.
The fruit was traditionally used to add a sour flavor to meals, but has now become popular for its effects on weight loss (1).
In the skin of the fruit is a large amount of a natural, biologically active substance called Hydroxycitric Acid (HCA).
This is a detailed review of garcinia cambogia and the science behind it.
How Does Garcinia Cambogia Work?
Many studies have been done on garcinia cambogia, in both animals and humans.
It has been shown to affect appetite and weight regulation in two ways:
- Fat Production: It blocks the fat-producing enzyme Citrate lyase. This makes it harder for the body to produce fat (4, 5).
- Cravings: It increases levels of the hormone serotonin in the brain. This can theoretically lead to reduced appetite and fewer cravings (6, 7).
However, what works in test animals doesn’t always work in humans.
Bottom Line: Studies have shown that garcinia cambogia reduces cravings and fat production. It causes significant weight loss in test animals.
Does it Actually Cause Weight Loss in Humans?
Fortunately, we don’t need to rely on animal studies here. The supplement has also been tested many times in humans.
The best evidence available is a review of 9 studies that looked at the effects of garcinia cambogia on weight loss in humans (3).
These were all randomized controlled trials, which compared garcinia cambogia against placebo (dummy pills).
The blue bars represent the garcinia cambogia groups, the orange bars represent the placebo groups.
As you can see, some studies didn’t find any difference, but quite a few studies showed significantly greater weight loss in the garcinia cambogia groups.
The average weight loss caused by garcinia cambogia is about 2 pounds (0.88 kg) greater than placebo (3).
Many of the studies were small, short in duration and had a number of design flaws. People were also instructed to eat healthy and exercise in most of the studies. For these reason, you should take the results with a grain of salt.
Interestingly, the single largest study with 135 participants did not find any effect of garcinia cambogia. Both groups lost a similar amount of weight (13).
If garcinia cambogia really works for weight loss, then the effect is fairly small and unreliable.
It may also depend on the individual, as well as the quality of the supplement.
Bottom Line: Studies in humans show that garcinia cambogia can increase weight loss by about 2 pounds over several weeks, on average.
Other Health Benefits
Garcinia cambogia has mainly been studied as a weight loss supplement, but it may also have other health benefits.
For example, one study showed that it can reduce LDL cholesterol, lower triglycerides and raise HDL (the “good”) cholesterol (17).
However, keep in mind that the evidence is mixed. Higher quality studies are needed.
Bottom Line: Although the evidence is mixed, some studies suggest that it can reduce belly fat and improve several risk factors for heart disease.
You can get garcinia cambogia extract from health food stores and online retailers.
It is recommended to get a brand that contains 50% or 60% hydroxycitric acid.
However, it is important to keep in mind that the quality of supplements is highly variable. They are not regulated by the FDA, and there have been many cases of fraud in the supplement industry.
Here’s how to take garcinia cambogia:
- Get a brand with 50% or 60% HCA.
- Take 500 mg, 3 times per day.
- The best times are 30-60 minutes before meals.
However, keep in mind that dosage instructions may vary between brands. Read the label and follow the instructions on the packaging.
Bottom Line: It is best to get a brand with a hydroxycitric acid (HCA) content of at least 50% or 60%. Take 500mg, 3 times per day, 30-60 minutes before meals.
Safety and Side-Effects
A 2012 review of the safety of garcinia cambogia did not find any serious side effects (20).
However, people who take it are about twice as likely to experience digestive problems (3).
Other commonly reported side effects:
- Dry mouth.
You should consult with a doctor before taking it if you have a medical condition or are taking any medication. Also avoid taking it if you are pregnant or breastfeeding.
All that being said, garcinia cambogia seems to be very safe for otherwise healthy individuals and the risk of toxicity is extremely low.
Bottom Line: Commonly reported side effects of garcinia cambogia include headaches, dizziness, dry mouth and digestive problems like diarrhea.
Should You Try Garcinia Cambogia?
According to the studies, garcinia cambogia can have modest effects on weight loss. It may help you lose about 2 more pounds over a period of several weeks.
However, same as with most weight loss supplements, it isn’t very effective on its own. You also have to eat healthy, exercise and sleep well.
Additionally, if you want to lose weight and keep it off, then you have to change your lifestyle for the long-term. Short-term “diets” only bring short-term results.