Although thinning hair and baldness are probably the biggest reasons to cover this body part, having a bad hair day may be reason enough to hide a disastrous do under a hat or a scarf. Hair provides great protection from the sun, but it's a symbol of health and attractiveness, too. If you know a middle-aged man who opts for the notorious "comb over" or thinks a ball cap is an appropriate accessory indoors and out, it's easy to see that hair is more than a thick structure of threadlike strands that helps protect the body from heat loss.
Androgenetic Alopecia is the scientific term for male pattern baldness (MPB), a condition that's prevalent in men but occurs in women, too. It's responsible for more than 95 percent of male hair loss and can lead to a receding hairline, a thinning spot or significant hair loss at the crown and beyond. The statistics can be alarming, especially if you're a man who prides himself on a full head of hair. Before the age of 40, two in three men will notice some degree of hair loss, and by the age of 50, those hairs going down the sink will represent significant hair thinning for 85 percent of men. Conservatively speaking, male pattern baldness affects 35 million men nationwide [sources: Thompson and American Hair Loss Association].