Hair loss at a young age is due to excessive anxiety. However, dandruff can also be due to allergies. Hair loss can also be caused by thyroid disease , anemia , and eating too much fast food. Try the following tips: Eat more foods rich in vitamins , zinc and iron. Ask them to drink plenty of water. Ask them to apply onion juice to their hair. Will do once a week. Ask him to apply fenugreek , neem leaves and amalki juice on his head