It is impossible to lose weight by chanting Buddhism. Buddhism is used to cultivate one's morality and cultivate one's nature. People who practice don't care about being tall or thin, so chanting Buddha is to cultivate the mind, not to lose weight.

If you want to lose weight, you must do two things:

Shut up. Control your diet. Eight meals a day is enough. Don't eat other snacks except fruit.

Lift your legs. Exercise is the healthiest way to lose weight. In sports, it can enhance physical fitness and give people health and beauty. Get up an hour early every morning and go out to play ball on weekends. Yoga half an hour before going to bed is a good way to lose weight healthily.