Hair is one of those inessential parts of the body, meaning that if your body is under stress or pressure, your body will focus on keeping you alive and healthy rather than having a full head of hair! There are many contributing factors:
Vitamin D deficiency: Because most people spend their time indoors, behind a desk, or on the couch, a surprisingly high percentage of the population has insufficient levels of vitamin D (which is synthesized in the skin through exposure to UV rays). Studies have shown that low vitamin D levels cause hair loss.
Too much vitamin D: High levels of vitamin D can also cause hair loss, which is why it is important to have the right balance.
Iron deficiency: Iron is important for your hair, nails, and skin. Too little can cause hair to fall out or make the hair follicles smaller so your hair strands end up being thinner.
Calcium deficiency: Calcium is also important for your hair, and if you are not getting enough vitamin D (which is needed for absorbing calcium), your hair may fall out.
Stress: Stress causes hair loss. This is widely known, and seeing your hair fall out can just add to that stress! It takes from 1 - 4 months after a stressful incident for the hair to start falling out.
Lack of sleep: If you are not sleeping well, this can also have a negative effect on your hair.
The type of shampoo you use: Shampoo may also be making your hair fall out. Natural shampoos are much better for your hair and scalp than chemically-based ones.
Food allergies: Various food allergies, especially to dairy, can cause your hair to fall out.
Coeliac (or Celiac, as it is known in the US) disease: It is not widely known that hair loss is a symptom of Coeliac, which is when the small intestine cannot break down gluten, and ingredient found in bread, pasta, wheat products, etc
Every human body is different , so we can not recognize the ans. , why? any one is facing hair loss problem. Consult once with hair specialist - http://www.marmm.com/prp-hair-loss-treatment/