Hair loss
New Zealand player Mark Nielsen is in the news today: tested positive for a banned substance, finasteride.
Expect more of these cases: finasteride is commonly found in hair-restoration products. It's banned because it can be used to mask steroids, but it seems so much more likely (and funnier) that they really are taking it because they're worrying about hair loss. Plenty of players on the men's tour with hair loss problems over the years (Sampras, Agassi the first who spring to mind).
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