Hi there, hope you are doing great. as per your provided information your weight should be 65 kgs so you are 12 kgs under weight. include calorie dense foods like nuts,cream,cheese,avocado, coconut milk,peanut butter,potaoes,dates. Eat small frequent meals. Gain weight in healthy way,avoid junk and fried food to gain weight. Keep yourself well hydrated. include one-two serving of vegetables, 1 serving of fruit have good source of proteins like soyabean,paneer,greek yoghurt,dals,pulses. If you are non-veg then add chicken,fish & whole eggs (2 a day).
Next Steps
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Health Tips
avoid walks after lunch & dinner