Thinning Hair Can Have Myriad Causes

Sometimes thinning hair is the reason you seek medical attention. It may be a matter of normal aging—or it could be related to an underlying (and possibly more serious) problem.

thinning hair

While thinning hair is probably not something you’re going to go your doctor about, you probably should.

© Piman Khrutmuang |

Forget using the hair you see in your hairbrush or bathroom sink as a gauge of thinning hair.  It’s normal to lose 50 to 100 strands of hair a day, says the American Academy of Dermatology Association (AADA). What makes thinning hair diagnosable is evidence of bald patches and sections of thinning hair. However, thinning hair is not uncommon—80 million of us experience it—and usually it’s due to heredity. When it is, it’s called: male pattern baldness, female pattern baldness, and androgenetic alopecia.

With heredity causes, men tend to see thinning hair as patches of missing hair at the top or back of the head or a receding hairline. Women, on the other hand, usually first notice that their part is getting wider. However, these symptoms can be seen in either gender. And both sexes do believe their hair is visibly thinning. While the AADA says the reasons for this are unclear, experts agree that if the cause is heredity, it’s not an easy fix.

Thinning Hair and Styling

Although you would need to go to an extreme to cause damage to your hair by the way you care for it, the fact of the matter is, it can indeed happen. Be aware that these typical hair care protocols can cause hair thinning and damaged hair:

  • Blow drying hair on setting that is too high
  • Hair styles that are too tight
  • Hair-styling products that are harsh
  • Overstyling

Researchers at Johns Hopkins say a common cause of hair loss and breakage known as acquired trichorrhexis nodosa, or TN—often more prevalent in African-Americans—can be remedied through appropriate use of cleansing products, hair care and styling practices.

“It’s imperative that we offer dermatologists and patients alike easy tips for resolving TN, one of the few forms of hair loss that can be resolved fairly quickly with nonmedical options,” says Crystal Aguh, M.D., assistant professor of dermatology at the Johns Hopkins University School of Medicine. “Our recommendations are acceptable for those of all ethnic backgrounds experiencing hair breakage, and dermatologists should feel comfortable discussing these techniques with every patient seen.”

In Journal of Dermatological Treatment, the Johns Hopkins researchers found that thermal styling tools, such as the use of flat irons and blow dryers, as well as chemical processing, such as permanent dye and straightening, tend to damage the protective outer layer of the hair shaft, called the cuticle. This can alter the hair’s protein structure, which causes the cortical fibers to be exposed and fray, leading to weak points where breakage occurs.

When Disease Causes Thinning Hair

It should come as no surprise that disease is a major player in hair thinning. If your body is in trouble, it will divert its resources to the area that needs it the most, away from bodily functions that aren’t critical. Hair growth is not critical. Similarly, a poor diet, lacking in proper levels of vitamins and minerals, can result in thinning hair because those nutrients are going to vital organs, not hair follicles.

While thinning hair is probably not something you’re going to go your doctor about, you probably should.  A dermatologist (medical doctor who specializes in skin diseases) can help determine if the cause of your thinning hair is primary or secondary.  If it’s secondary, you are probably experiencing other symptoms you’re ignoring, such as fatigue or very dry skin, that may indicate a more serious underlying disease.

With most of the diseases listed below, thinning hair or hair loss is listed as a symptom. Curing the disease—or least treating it if there’s no cure—can help reverse thinning hair:


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How the Doctor Can Help

Speaking at the 68th Annual Meeting of the American Academy of Dermatology (Academy), dermatologist Mary Gail Mercurio, MD, FAAD, associate professor of dermatology and program director of dermatology residency at the University of Rochester (N.Y.), discussed common forms of thinning hair in women and available treatment options.

“In the past, many women experiencing hair loss would suffer in silence, not knowing where to turn for help and trying their best to hide the problem,” said Dr. Mercurio. “But now, I see more and more women in my practice seeking treatment for hair loss and actively addressing this condition. That’s encouraging, as the sooner hair loss is diagnosed, the better our chances of successfully treating it.”

In some cases, Dr. Mercurio explained, a hormonal abnormality, such as excess male hormones known as androgens, may be responsible for hair thinning or hair loss in women. One clue that hormones are involved is if the hair-loss pattern resembles that of a man’s hair loss. While female-pattern hair loss caused by a hormonal imbalance can be treated with prescription medications, such as spironolactone or oral contraceptives, it is important that women see their dermatologist for proper diagnosis and treatment.

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Cindy Foley

Cindy Foley is the editor of several health reports, including Managing Your Cholesterol, Core Fitness, and Brain Power & Nutrition, among others. Foley has worked in the private medical practice field … Read More

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