Which is the best foods for an underweight person to eat?

Here is my list: Milk, milk poroductss uch as ice cream khoya based-sweets, cheese/paneerand yogurt. All nuts liek almonds and cashew are great. Any meats and eggs in any form are rich in calories. Eat 3 times a day and at bed time add a and extra snack.

As for anyone: Enough protein. Avoid very greasy / sugary / salty. Eat when you're hungry and be sure you're exercising regularly. Remember that many elite track-and-field athletes are "underweight". To put on lean muscle, if that's your goal, hard resistance training until you grunt and sweat, daily working different groups. If you're lost weight recently and don't know why, your physician needs to work you up.