Thank you for your query.
Would you please clarify a few things for me?
1) what is your height/BMI(
body mass index)?
2) describe your diet please.
3)do you have medical issues that you know of (
thyroid hormone imbalances, for instance)?
4) do your parents also have a physical stature similar to yours?
5)do you smoke? Exercise?
Balanced nutritional value foods are important for a healthy body. Adequate amount of
proteins and proper exercise is required to build muscle mass.
If you are a vegetarian, lentils, beans, chickpeas and a host of lentils and grains are rich in protein. Animal protein (fish, meat, chicken and egg) is an option for non vegetarians.
Exercises that target building muscle mass include weight and endurance training.
I recommend you see a nutritionist and fitness expert who could advice as to what is best for your physical stature, metabolic needs and goals.
If that doesn't help or start to show improvement in a couple of months, I suggest you see physician who could rule out
hormonal, genetic cause for the low weight (if that's the case)
Remember, do not medicate or take supplements without consulting with a specialist. Some products and medications can have severe adverse health effects which may be irreversible.
Hope this helps. Please feel free to contact us if you have any questions
Wish you good health.