Why Some Men Can't Grow Beards

Beards seem to be everywhere nowadays, but some men just can't grow them. Why not? What goes into growing a great beard?

Beards rotate in and out of fashion on some unknowable cosmic schedule, but for many men it's a moot point. Not everyone can grow a beard, and there's not much that science can do about it. The admirably bewhiskered Jules Suvdaltsev has the story in today's DNews dispatch.

Most people who find themselves thinking about the issue associate beards with testosterone levels, but that's only part of the story. Testosterone is part of a group of hormones called androgens, which regulate, among other things, male secondary cell characteristics. That covers physical attributes usually associated with men, but which are not directly involved in reproduction. Like beards.

But testosterone levels alone don't determine beardiness. Years of research have more-or-less confirmed that a chemical called dihydrotesterone , or DHT, induces beard growth. DHT is essentially a super-potent form of testosterone, but here's the weird twist: DHT also causes hair growth

Whether and when you can grow a beard is chiefly determined by the number of androgen receptors in skin to which DHT can bind itself. If you have a lot of these receptors on the bottom of your face, your beard shall flourish in glory. Androgen receptors in the scalp, however, will trigger DHT to induce what doctors politely refer to as regression -- that is to say, baldness. Paradoxical and tragic, but true.

If you're cursed with a scraggly beard, there's not much you can do about it. The number of androgen receptors you have seems to be ultimately decided by genetics. And while there are medications that can lower the amount of DHT in your body -- which is how some people fight male-pattern baldness -- there is little you can do to boost your number of androgen receptors. (Double Secret Bonus Fact: Caffeine might help a little.)

The bottom line: It's all about genetics. Jules has more details in his report.

Read More:

BBC: The real reason men grow beards

NY Times: Oh, to Be Just Another Bearded Face

Mental Floss: Why Can't Some Men Grow Facial Hair?