You can't lose 20 pounds. If you lose weight, it must be morbid. If you want to lose weight healthily, safely and effectively, you must first combine diet and exercise to lose weight. Don't overeat every day, eat three meals regularly, don't eat fried food, don't eat high-calorie food, eat more crude fiber food, eat more fruits and vegetables, choose light food, refuse heavy taste, it is best not to eat snacks, and insist on aerobic exercise for a period of time every day.