28 Sep 2016
People suffering from dwindling hair quality and baldness are often concerned about how fast their hair grows. Well, the answer is that scalp hair grows half an inch every month. Genes are largely responsible for any positive or negative fluctuation in this estimate. Also, pregnant women can experience faster hair growth. Continue reading to know the science behind hair growth.
Hair follicles, of which there are about 5,000,000 in the human body, are designed to produce hair shafts. Over time, human beings have come to being less hairy than their earlier generations. Evolution, movement patterns, and climate changes have led humans losing dense tufts of hair from the body. Hair on the head saves them from the sun and the cold, in different climates. On the other hand, eyelashes protect the eye against dust and bugs.
Hair grows out of small pockets called follicles. It starts from the root, made of cell proteins. Blood vessels scattered on the scalp feed these cell proteins. Upon the generation of more cells, hair grows along and passes oil glands on the way. The hair shaft emerges from the pit of hair follicles and can be strengthened by regular deep conditioning and hair spa.
Keratin is a hard protein that makes up the hair shaft. It has three principal layers, the medulla, the cortex and the cuticle, which is the outermost layer. The hair's pigment is held by the inner layers, the cortex and the medulla.
Hair growth takes place in three stages, which are anagen (growth), catagen (rest phase), and telogen (hair fall phase). In the first, cell division in the root happens at a prolific rate. The hair grows to about 1 cm every month or so. This happens from about 2 to 6 years of age for scalp hair. This duration depends on genes. In catagen, the hair follicle shrinks to about a sixth of its original length. In the final stage, telogen, about 100-150 strands of hair are shed every day. However, if it is more than that, one should seek hair loss treatment.