I am having a low body mass index. My height is 177 cm and weight is 55 kg. What should I do.

Hi, do regular exercise. Take 2 banana with warm milk in the morning. Eat soaked dry grapes or dates soaked in warm milk overnight. Include protein rich food in your diet like soyabean, sattu with milk, sprouts, milk and milk products, combination of cereals and pulses, take healthy and heavy breakfast. No drink before meals. Take small and frequent meals.

Weight gain is muscle gain and not fat gain. In your condition your energy requirement is very high so whatever you eat is used as a source of energy and you do not make muscle. To gain muscles you will have to eat at least 6 meals (high calorie) in a day at a regular interval with a proper ratio of proteins and carbohydrates. Proteins will help you gain body mass while carbohydrates will help you give energy. Protein foods are eggs, fish, chicken, milk and milk products, meat and dals. Carbohydrate foods are roti and rice, potatoes, sweet potatoes. You have to eat vegetables and fuits and use healthy and good fats for cooking like ghee, cold pressed mustrad or til oil. You will also have to do some weight training exercise to help you build mass into the body. Also drink enough water to keep you hydrated.