Hi, From history it seems that your weight is much less. first go for investigations like complete blood checking, urine check up and x-ray chest to rule out any underlying disease. Go for hemoglobin testing for anemia. To increase your appetite take Ciplactine tablet or syrup. Take high protein diet like butter, ghee, milk, puddings, cheese, panier, pulses and cereals. Take dry fruits. Take fresh vegetables and fresh fruits and juices. Take Iron capsules and some multivitamin supplements. Ok and take care.