what causes hair loss?

JAB

It depends on what type of hair loss.

Most common cause in men is elevated levels of dihydrotestosterone (DHT).

Most common reason in women is hypothyroidism as unopposed estrogen suppresses the thyroid.

Other causes include nutritional deficiencies, heavy metal poisoning, and autoimmunity.

After pregnancy many women experience a loss of hair, this is caused many hair simultaneously entering the resting (telogen) phase. Within two to three months after giving birth, some women will notice large amounts of hair coming out in their brushes and combs. This can last one to six months, but resolves completely in most cases. This condition is caused by the hormonal changes that take place after a woman's body recovers from her pregnancy.

Sometimes one to three months after a high fever, severe infection or flu, a person may experience hair loss, this is usually temporary and corrects itself.

Both an overactive thyroid and an underactive thyroid can cause hair loss. Thyroid disease can be diagnosed by your physician with laboratory tests. Hair loss associated with thyroid disease can be reversed with proper treatment.

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