There are many different weight loss solutions out there.
This includes all sorts of pills, drugs and natural supplements.
These are claimed to help you lose weight, or at least make it easier to lose weight combined with other methods.
They tend to work via one or more of these mechanisms:
- Reduce appetite, making you feel more full so that you eat fewer calories
- Reduce absorption of nutrients like fat, making you take in fewer calories
- Increase fat burning, making you burn more calories
Here are the 12 most popular weight loss pills and supplements, reviewed by science.
1. Garcinia Cambogia Extract
Garcinia cambogia became popular worldwide after being featured on the Dr. Oz show in 2012.
It is a small, green fruit, shaped like a pumpkin.
The skin of the fruit contains hydroxycitric acid (HCA). This is the active ingredient in garcinia cambogia extract, which is marketed as a diet pill.
How it works: Animal studies show that it can inhibit a fat-producing enzyme in the body and increase levels of serotonin, potentially helping to reduce cravings (1, 2Trusted Source).
Effectiveness: One study with 130 people compared garcinia against a dummy pill. There was no difference in weight or body fat percentage between groups (3).
A 2011 review that looked at 12 studies on garcinia Cambogia found that, on average, it caused weight loss of about 2 pounds (0.88 kg) over several weeks (4).
Side effects: There are no reports of serious side effects, but some reports of mild digestive problems.
Hydroxycut has been around for more than a decade and is currently one of the most popular weight loss supplements in the world.
There are several different types, but the most common one is simply called “Hydroxycut.”
How it works: It contains several ingredients that are claimed to help with weight loss, including caffeine and a few plant extracts.
Effectiveness: One study showed that it caused 21 lbs (9.5 kg) of weight loss over a 3 month period (5).
Side effects: If you are caffeine sensitive, you may experience anxiety, jitteriness, tremors, nausea, diarrhea and irritability.
Caffeine is the most commonly consumed psychoactive substance in the world (6Trusted Source).
It is found naturally in coffee, green tea and dark chocolate, and added to many processed foods and beverages.
Caffeine is a well known metabolism booster and is often added to commercial weight loss supplements.
How it works: Short-term studies have shown that caffeine can boost metabolism by 3-11%, and increase fat burning by up to 29% (7Trusted Source, 8Trusted Source, 9, 10).
Effectiveness: There are also some studies showing that caffeine can cause modest weight loss in humans (11Trusted Source, 12Trusted Source).
Side effects: In some people, high amounts of caffeine can cause anxiety, insomnia, jitteriness, irritability, nausea, diarrhea and other symptoms. Caffeine is also addictive and can reduce the quality of your sleep.
There really is no need to take a supplement or a pill with caffeine in it. The best sources are quality coffee and green tea, which also have antioxidants and other health benefits.