Hair loss occurs due to the deficiency of iron in the body. Not necessarily because of iron deficiency or nutrition deficiency. It may also happen because of genetic disease or due to radiation therapy which happens to the cancer suffering patients. 

The hair fall may happen on head or on the body. Usually for men they lose the hair on the head. Hair loss is also called as Baldness or alopecia.

There are some ways by which we can come to know whether there is a hair loss problem. Hair loss happens in circular form, dandruff, abnormal growth of skin in some part of the body. Loss of excessive hair in the hairbrush after brushing the hair or in the basin after taking the shower.
The best way to know whether there is a hair loss problem is to check hair brush or basin after taking the shower. If the excessive hair is lost daily then there is definitely hair loss problem. 
There are many causes of the hair loss. Let us discuss some of it here. 
Nutrition deficiency
Humans need to nutrition’s externally to. Humans actually require a lot of nutrition’s. If there is lack of nutrition he may tend to get diseases or some infections. Study says deficiency of iron in the human body causes hair loss problem. 
Hair loss problem also cause due to some infections. The infections may be fungal infections, folliculitis and Demodex folliculorum. These infections cause hair loss problem. 
The intake of drugs into the body also causes the hair loss problems. Drug can be in any form it may be in the form of smoking, drinking and other modern ways of drug intake. Sometime due to some of the medicines the hair loss problem occurs for example Chemotherapy or radiotherapy. 
Sometimes due to air and water pollution it may cause the hair loss problem.


Pull Test
In this we can evaluate diffuse scalp hair loss. A gentle force is applied on the group of hairs and should be pulled. In each pull less than or equal to 3 hairs if more than 10 hairs come then test is considered to be positive.

Pluck Test
In pluck test a group of hairs is pulled out and should be examined under the microscope. The growth of hair is studied. 
Scalp biopsy
Scalp biopsy is done when the root of the problem is unknown. Hair is usually taken from the inflammation area. 
Daily Her Counts
The best way to find out the hair loss is to count the hair loss on a daily basis after brushing hair or washing. It should be collected in a bag for 14 days. In the end the hair lost per day is greater than 100/day then it is counted as positive.


Hair Transplantation
Hair transplantation is one way to overcome the hair loss problem. Though it is bit expensive one but it gives permanent solution to hair loss problem. Hair transplantation gives you result similar to natural hair growth. Though it takes around 2-3 months but it gives the accurate results in a desired way. 
The surgeon who is doing the hair transplantation should be very expert and experienced one as it gives the more desired result. 
Hair transplantation is of two types.
1.Strip Harvesting 
2.Follicular Unit extraction
Wearing wig is a less expensive way to hide the hair loss problem. Its bit economical compared to hair transplantation.

Apart from these two there are certain specific homemade remedies in India they are

Add a drop of lime to the washing hair which prevents hair loss problem.And wash the hair daily it will prevent hair loss. 
Wash the hair with pure water and warm water and rinse thoroughly. It will prevent hair loss subsequently. 
Drink of plenty of water
Cut caffeine
Get good sleep about 7 to 8 hours a day. 
Apply coconut oil daily 
Keep the hair clean
Avoid chemical treatment
Never apply the Chemical colors

By above steps and with advice of Doctors you can avoid the hair loss problems.