Male sex hormones are responsible for shortening the lives of men, a new study has suggested.
“This discovery adds an important clue for understanding why there is a difference in the expected life span between men and women,” Kyung-Jin Min of Inha University said.
The castrated boys in Korea lost their reproductive organs in accidents —usually after being bitten by dogs or underwent castration purposefully to gain early access to the palace.
Eunuchs were allowed to marry and had families by adopting castrated boys or normal girls.
People in those days kept careful genealogy records as proof that they were of the noble class.
By poring over those records, Min and colleague Cheol-Koo Lee of Korea University found that eunuchs lived 14 to 19 years longer than other men did.
Amongst the 81 eunuchs they studied, three lived to the ripe old age of 100 or more, a feat of longevity that remains relatively rare even in developed countries today.
The incidence of centenarians among Korean eunuchs is at least 130 times greater than it is in the developed countries, Lee notes, and that can’t be explained simply by the benefits of life in the palace, either.
Most eunuchs spent as much time outside the palace as they did inside it. And, in fact, kings and male members of the royal family had the shortest lives of all, typically surviving only to their mid-forties.
The study has been published in Current Biology.