Hello,
As a mother, I can understand your concern. Since your son is losing weight he might not be eating well. Sudden loss of weight will result in weakness. Take care of his regular diet.
Give him homemade nutritious food. Vegetarian food is equally nutritious, give him fruits, dry fruits, dairy products(eggs, cheese, paneer, milk, yogurt, etc).
Give him juice, soups, warm beverage (Horlicks, milk, viva, complan, etc) from time to time.
It looks like he is doing some research work. Well, that's good. You need not worry. There is no harm in eating chicken or mutton, it will help him in his studies. The brain also requires energy.
Explain to him that he needs adequate rest, so that he sleeps in time( he should take at least 4-5 hrs of sleep).
To avoid withdrawn behavior go with him outdoors for some shopping or work. Invite his friends home. It will be better to take the help of a Counselor to assess if he is under
depression.
If he is not under depression, you need not worry. Just leave him & see what makes him happy.
He might be having anxiety-induced
insomnia. Help him relax, if he likes music, let him play it.
If required he can take some sleep medications after clinical check-up. He will be fine after he has completed his research work.
Hope I have answered your query. Let me know if I can assist you further.
Take care
Regards,
Dr Nupur K, General & Family Physician