Male sex hormones may be responsible for shortening the lives of men as compared to women, a new study has claimed.
Researchers in Korea found that eunuchs - castrated men living centuries ago - outlived others by a significant margin due to absence of such hormones.
The evidence comes after careful study of genealogy records of noble members of the Imperial court of the Korean Chosun dynasty (AD 1392-1910), the Daily Mail reported.
"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.
By poring over records, Min and his 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 age of 100 or more, a feat of longevity that remains rare even in developed countries today.
They noted the incidence of centenarians among Korean eunuchs is at least 130 times greater than it is in the developed countries, and that can't be explained simply by the benefits of life in the palace, either.
Researchers said most eunuchs spent as much time outside the palace as they did inside it. And kings and male members of the royal family had the shortest lives of all, typically surviving only to their mid-forties.