A. The 20-30 diet promises to help you lose 20 pounds in 30 days by altering seven key hormones that make losing weight difficult, including insulin, cortisol, and sex hormones like testosterone and oestrogen. It aims for 20 to 30 grams of protein for each meal to stay more satiated, including around three ounces of chicken, fish, or beef, a bowl of lentils or tofu, or a cup of Greek yoghurt or cottage cheese.