Proper cooking can effectively reduce the amount of fat that enters the body and can aid in weight loss. Eating raw onions and making salads with onions can assist in weight loss. Onions contain cellulose, this substance on the body of the gastrointestinal tract of the muscle of the movement of the stimulating effect, can help the human body to relieve the symptoms of constipation, discharge excess metabolic waste, but also to avoid the accumulation of toxins because of the gastrointestinal tract and produce side effects, can play a role in weight loss. Onions also contain a lot of vitamins, to maintain the endocrine balance in the body has an important role, can promote the relative proportion of various nutrients balance, to maintain the balance of oil and water on the surface of the skin, a variety of nutrients metabolism is gradually restored to balance, can help to lose weight. Onions in the flavor of the material, can play a role in promoting digestion, will also help to lose weight.