Excellent piece from the excellent Lucy Inglis. I haven’t lifted the para about how they castrated young boys. Read it at your peril. But this is what it did to them:
Growing up as a castrato couldn’t have been much fun. They grew tall, with long ribs, arms and legs, making them an unusual, gangly barrel-shape. Even if their voice didn’t break, there was no guarantee that it could be trained into a world-class opera ‘voice’ and most ended up singing in cathedral choirs. They were prone to weight gain, and had chubby, androgynous faces. Their hair was thick and fine, as early castration prevents male-pattern baldness (the thing that works, but no one wants the cure) and they rarely wore wigs. No facial hair, and little body hair spoiled the picture of smooth childhood grown to adult size. Much is made of the ladies of the 18thC going wild for castrati, but whilst they may have been charming and talented company, their penis remained child-sized and their sex drive was low.