Hair loss is a natural phenomenon in all hair bearing animals including human beings. On an average, a person loses (assuming they have a head full of hair) about 100 scalp hairs over a 24-hour period. Hair loss becomes bothersome or a cosmetic problem when it occurs in the wrong place at the wrong time. Hair loss is of different types and occurs in many different ways depending on the underlying cause (the problem that's causing it). It can occur gradually or rapidly and may affect just the scalp or your whole body. In addition, hair loss can either be temporary or permanent.
Some symptoms of hair loss include:
Gradual thinning of hair on top of head: This is the most common type of hair loss that occurs in both men and women. The site at which hair loss occurs on the scalp is different in men and women. In men, the hairline recedes in the beginning followed by thinning of the hair on the crown and temples. A horseshoe shape of hair remains around the back and sides of the head. Only rarely does hair loss progress to complete baldness in some men. In women, the hairline at the forehead is not affected. While some women may experience broadening of a part of their scalp, other women may lose hair from the top of their head only. This usually occurs after menopause.
Circular or patchy bald spots. At times, hair loss can appear as smooth bald spots often about an inch (2.6 centimeters) in diameter. The skin of the bald patches is healthy. It usually affects the scalp, but may also occur in beards or eyebrows. Some people may experience itching or pain in the scalp before the hair falls out. This type of hair loss is known as alopecia areata. If the bald spots are present mainly around the hairline, it is called an ophiasis pattern. Most people with alopecia areata have no other symptoms, though in about 10% (1 in 10 people), the finger nails may also be affected. Sometimes, in alopecia areata, hair may grow back in the bald patches.
Sudden loosening of hair. The hair may loosen after a serious physical or emotional shock. You may notice handfuls of hair come out while combing or washing hair or even after gentle tugging. There is an overall thinning of hair in this type of hair loss and not bald patches.
Full-body hair loss. After some illness or medical treatments, such as chemotherapy for cancer, loss of hair may occur all over the body. In most people with this type of hair loss, the hair usually grows back after treatment is stopped.