Here’s a joke: How do you guarantee you’ll still have a little hair left by the time you turn 60? Answer: Start with a lot. The truth is, most guys shed between 50 and 100 hairs every day, according to the Mayo Foundation for Medical Education and Research. That’s no big deal, so long as your scalp is sprouting enough to replace them. Over the course of your life, however, a handful of events can interfere with that growth cycle, causing your head to lose more strands than it grows. In fact, 85 percent of men experience some hair loss by age 50. We asked Marc Glashofer, M.D., a board-certified dermatologist who specializes in hair fall about some common causes of hair loss in men.
READ MORE: The Fatherly Guide to Genetics
1. Androgenetic Alopeci
There are 200 genes that regulate various aspects of your hair, from coarseness to color to curls. And also, the age at which you lose it. Commonly known as male-pattern baldness, this hereditary condition affects up to 50 million men and can begin as early as your teenage years. Frequently characterized by a receding hairline in a distinct “M” shape on your head, male-pattern baldness is related to testosterone levels. “This is the most common cause of hair loss in men and due mainly to genetics,” says Glashofer. “Basically, in some men, the hair follicles are more sensitive to testosterone, which leads to thinning and balding.” (In more technical terms, DHT, a testosterone derivative, binds to the hair follicle and shrinks it, making it impossible for healthy hair to grow, according to the American Hair Loss Association.)
“When I’m seeing a patient for the first time, one of the first things I want to rule out is an iron deficiency,” says Glashofer. Lack of the mineral in your body (also known as anemia) can lead to brittle or thinning hair. Other things Glashofer looks for: Low levels of biotin, vitamin B12, and zinc. That said, “unless you’re following some really wacky diet or being really restrictive in what you eat, most men are probably getting enough of what they need to grow healthy hair.”
3. Severe Stress
To clarify, “we’re not talking about a lousy commute,” says Glashofer. Significant physical stress, such as surgery or illness, or an emotional one like job loss, can lead to a condition known as telogen effluvium. According to the American Osteopathic College of Dermatology, it can cause a person to lose up to 70 percent of their hair over the course of several months. The reason: “A big stressor like this can cause a shift in the body’s hair production cycle, which leads to extra shedding,” says Glashofer. “The good news is that your body will re-regulate its hair production over the course of about six months.”
4. Alopecia Areata
If you’ve ever seen those round, shiny bald patches on another guy’s head (or maybe on yours) it could be alopecia areata, a condition that affects 6.8 million Americans. “Alopecia areata is an autoimmune condition where the body’s immune system begins to attack its own hair follicle, causing hair to fall out,” says Glashofer, who suffers from this disorder. “It often occurs earlier in life, but men can experience it at any time.”
Some drugs, like those used to treat depression, high blood pressure, and arthritic conditions, have potential hair-loss side effects. Even non-steroidal anti-inflammatories such as ibuprofen have a possible hair-loss side effect, but context is important, says Glashofer. “I always ask patients how long they’ve been taking their medication, and how recently their hair loss began,” he says. “If someone’s been taking blood pressure medication for years, it’s not likely to be the cause of a sudden thinning of their hair.”
One lab-created product that will definitely hit fast-forward on hair loss: Anabolic steroids. On the unlikely chance that you feel the need to shortcut your fitness with these muscle-building drugs, know that they will shrink your hair follicles much the way your natural testosterone does in male-pattern baldness — but this time, at hyperspeed. Fortunately, the solution is simple: Don’t take them.