By Stephanie Stahl

PHILADELPHIA (CBS) — About 2% of Americans have alopecia. That’s roughly 7 million people. While it doesn’t make people sick physically, it can be emotionally distressing.

On Instagram in December 2021, Jada Pinkett Smith said she has alopecia, which causes hair loss.

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The 50-year-old movie star, married to Will Smith, said the hair loss happened suddenly in patches and that prompted her to shave her head.

“I’m very proud of Jada for discussing alopecia because there are so many women who experience it and they feel ashamed and they try to hide it,” Dr. Susan Taylor said, “so to have a woman who is self-confident, who explains her experience, who doesn’t wear a wig, I can’t begin to tell you how much I admire her.”

Taylor, a dermatologist with Penn Medicine, says there are different kinds of alopecia.

Jada has said hers is caused by an autoimmune disorder.

“It simply means that some of the cells in our bodies, called T lymphocytes, are attacking the hair follicles and making the hair fall out,” Taylor said. “This is a problem that we see not uncommonly. It can occur in women of any race and ethnicity and it occurs in men as well.”

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When caused by an autoimmune disorder, it’s called alopecia areata. It’s unknown what triggers it and it can happen on different parts of the body.

“It’s different in everyone,” Taylor said. “For some people, they can get patches of hair loss. Some people can get complete hair loss in some areas.”

Taylor says there’s also something called traction alopecia, associated with braids and weaves that happens primarily among African Americans.

Depending on the cause, there are several promising therapies for alopecia that work best when treated quickly.

The most common treatment for alopecia is powerful, anti-inflammatory drugs that can suppress the immune system.

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The condition can happen at any age, but it most often strikes teenagers and young adults.

Stephanie Stahl