Garlic has been used both as food and as a medicine for hundreds of years. In an experiment with rats, garlic helped prevent weight gain, but its effects have not been tested in humans. So far, the only way to lose weight is to burn more calories than you consume, and it is not clear how garlic would help in this process.
Garlic and Weight Loss
Garlic's potential properties as a weight-loss aid have been tested in animal models, particularly one component of garlic called allicin. When rats were given allicin and then fed a high-sugar diet, they had lower blood pressure and insulin levels and weight gain than rats not given allicin. This suggests that garlic may help with weight loss, though more research needs to be done on humans.
Although garlic is a commonly eaten food and is generally safe, it can cause some problems. Common side effects include an upset stomach, bad breath, body odor and bloating. Garlic may also thin the blood, which can make people more prone to bleeding and bruising. Anyone planning on consuming garlic supplements or eating more garlic should talk to a doctor to ensure it is safe for them.