The human body is intriguing indeed. The different organs with their different functions play a very important role in our day-to-day life. The same can be said about the hair. We see hair on our head, our skin and everywhere else, apart from our palms and soles of our feet. Some of the hair is so fine, that it almost seems to be invisible.
Ever wondered how the growth and fall of hair works? We see people around with beautiful long hair, while some complain of hair not growing beyond a certain length. These are all dependent on several factors related to the body and mostly, the scalp.
The hair grows from follicles, which are present on the scalp. A baby is born with all the follicles possible, from which the hair can grow in its lifetime. These follicles cannot be generated again at any stage of life. As one grows older, they begin to expand.
The hair consists of a protein called keratin, which is produced in these follicles.  Humans have an average of 100,000-150,000 hair strands. It is normal to lose up to 90-100 strands of hair per day, so finding some strands of hair in the comb, is not a matter of major concern. 
ANAGEN: It is the active period where new hair grows on the scalp. During this time, the hair is said to grow 1cm every 28 days and the hair remains active in this phase for 2 - 6 years. After this, the follicles move on to the next phase.
CATAGEN: This phase leads to the development of the club hair. It lasts for about 2 – 3 weeks. The growth of hair stops and the roots get firmly attached. This precedes the resting phase.
TELOGEN: The hair is fully formed and remains in this stage for up to 3 months after which, the hair loosens itself from the root and finally moves out to be shed. In the meantime, the next hair prepares itself to take its place.
• With old age, the hair starts thinning and more stands of hair go into the resting or the telogen phase resulting in hair fall.
• Having long hair or short hair is often dependent on the genes of a person. It may be the cause of Balding, long hair, short hair or early greying of hair.
• Taking too much stress can cause an increase in hair fall.
• Medical conditions like diabetes or side effects of medication can result in excessive hair loss.
• Use of too much heat, or tight hairstyles, can make the hair rough and brittle. This also results in hair fall.
Avoiding too much Sun exposure will help the hair from becoming brittle and will prevent sunburns on the scalp. Eating healthy is necessary, so one’s diet should consist of proteins like in fish, some calories, Vitamin A like in spinach and low fat foods. Also, a stress free lifestyle with regular washing and maintenance will ensure good and healthy hair.
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