Thinning Hair

Thinning hair

Thinning hair is one of the more common symptoms of an underfunctioning thyroid gland, and it is also very common after pregnancy. It's a popular myth that thinning hair is a "man's issue". In fact, by age 50, nearly half of men and women experience some degree of hair thinning.

In the case of hereditary hair thinning (also known as androgenetic alopecia), the big difference between men and women is where their hair thinning occurs. Men's hair tends to thin out around the hairline, at the back of the head, and at the crown; a woman's hair thinning is more spread out over the area between the bangs and the crown of the head. This is why we hear men refer to "bald spots" and "receding hairlines", while women refer to "see-through" hair.

Hair is thickest at around age 20. After that, a combination of factors prevents the hair from following its regular growth process. Aside from the natural aging process, there are other reasons why a woman's hair may begin thinning - ranging from temporary conditions to medical disorders.

What Causes Thinning Hair

Thinning hair is a natural part of aging and is common even among the healthiest women. Once you pass age 20, you shed more than the normal 40 to 100 hairs a day. Then a combination of factors, including heredity and hormones, causes some hair follicles to get smaller and smaller. Normally, hair grows about a half-inch per month, but this "miniaturization" of the hair follicles prevents the hair from following its regular growth process.

In addition to the natural aging process, particular situations may cause hair thinning, including hypothyroidism (an underactive thyroid gland), anemia (low red blood cells), poor diet, certain medications, stress, childbirth, and perimenopause (the time leading up to menopause). Fortunately, this type of hair thinning is usually reversible, once the underlying cause is treated.

By far the biggest cause of thinning hair in women is a persistent condition called androgenetic alopecia, also referred to as "hereditary hair thinning". Hereditary hair thinning affects more than 30 million women in the United States.

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