He is small.. later on he will gain weight. It's always recommended to be slim. Any energy boosters or weight gaining medicines are harmful lateron. If all are lean in your family...then it's genetic. If every one in your family is quite healthy....then do not worry, he will puton.

Thanks Roopashree.  Yes. He is very Much  active.    But his appetite is also low.

If he is active, doing his daily activities without being tired&nbsp; and is healthy then no need to worry I guess. urad dal related recipe, dry raisins, cashew, pumpkin halwa, mangoes, grapes, banana all these help to puton. <br> But I suggest if he is healthy let him be lean. Anyhow after their academics they will puton later in life.