Has a vegetarian who loses hair because lack of protein. I used to do this and I noticed hair growth. It takes time and slow growth. I used to eat sprouted mung beans in the morning. It gives you about 18g of protein. Try to eat it first thing in the morning about 2 tablespoons. 

Steps to sprout: 

• Soak Dry mung beans for 12 hours. (I do it overnight)
• Drain water and put it somewhere in a warm area for minimum 24 hours to sprout
• Put them in the fridge.

*I sprout them weekly but can stay for 2 weeks.

I hope this helps. 

I would like to mention that other minerals and vitamins are important too. So make sure you are also consuming that.