I can understand your concern.
as it is you say that you are thin and yet you are 5.7.
height depends on a lot of factors, to name a few these factors would be, genetic, nutritional and some diseases.
if you do not suffer from any hormonal disturbances, then you will grow as per your parents height.
kindly consult a dietician for a diet to increase your weight.
Dr. Anil kumar jain.
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