Hair loss (alopecia) can affect just your scalp or your entire body, and it can be temporary or permanent. It can be the result of heredity, hormonal changes, medical conditions or a normal part of aging. Anyone can lose hair on their head, but it's more common in men.
Baldness typically refers to excessive hair loss from your scalp. Hereditary hair loss with age is the most common cause of baldness. Some people prefer to let their hair loss run its course untreated and unhidden. Others may cover it up with hairstyles, makeup, hats or scarves. And still others choose one of the treatments available to prevent further hair loss or restore growth.
Symptoms:
• Gradual thinning on top of head: This is the most common type of hair loss, affecting people as they age. In men, hair often begins to recede at the hairline on the forehead.
• Circular or patchy bald spots: Some people lose hair in circular or patchy bald spots on the scalp, beard or eyebrows. Your skin may become itchy or painful before the hair falls out.
• Sudden loosening of hair: A physical or emotional shock can cause hair to loosen. Handfuls of hair may come out when combing or washing your hair or even after gentle tugging.
• Full-body hair loss: Some conditions and medical treatments, such as chemotherapy for cancer, can result in the loss of hair all over your body. The hair usually grows back.
• Patches of scaling that spread over the scalp: This is a sign of ringworm. It may be accompanied by broken hair, redness, swelling and, at times, oozing.
Courtesy: Mayo Clinic