How does green tea extract help me lose weight?

Green tea extract contains compounds called catechins that may affect how your body burns calories and metabolizes fat. The research is preliminary, however, so it’s too early to say that green tea extracts, or green tea as a beverage, are effective in helping you lose weight. Be aware that green tea extracts may also contain caffeine, so if caffeine makes you jittery, be careful.

Green tea extract, as a weight loss supplement, works by decreasing your appetite and increasing your calorie and fat metabolism. While this supplement may be able to increase your calorie burn, it is still not known if it is completely safe.