Most of those affected put it down to suddenly having to wear metal helmets or tight-fitting hats. We assumed it made them sweat more and this made the hair more likely to fall out. In fact, the hair usually grew back again after a while which confirmed our theory. They obviously all got used to wearing this protective headgear. But I was chatting with friend in the US recently and she commented that many of the men returning from combat duty in Iraq and Afghanistan are coming back bald. This is not the short hair cut favored by the military, but real baldness.

So I hit the books and here I am again with the answer. It turns out that the stress of combat causes hair loss. It’s called telogen effluvium. It has nothing to do with male-pattern baldness. It’s just a coincidence that some men in the military start to show the conventional pattern baldness called androgenic alopecia which research now shows is caused by a break in the genetic sequence in your body. All these men have to do is take propecia and the hair loss stops. For the soldiers, all they have to do is to stay calm.

When hostile locals are triggering IEDs on the roadside as you drive past, shooting at you and generally aiming to maim or kill you, it’s not that easy to stay calm. But, until you reduce stress levels, the hair is not going to regrow that fast. Using propecia will have no effect at all. If you cannot control the anxiety, there’s one good thing. Your hair will grow back again when you leave the military - assuming you find civilian life less stressful and assuming you do not also have androgenic alopecia.