A study of genealogical records from the Korean Chosun dynasty (AD 1392-1910) has revealed an interesting method of prolonging life. According to the study, castrated males from the dynasty lived significantly longer than other males.

Eunuchs from the dynasty lived on average 14 to 19 years longer.

The meticulous records studied originated from people who needed to prove their nobility through a family tree.

Of the 81 eunuchs looked at, 3 of them achieved an age of 100 or greater. Something that is rare today even with modern medicine.

Kyung-Jin Min, of Inha University, said: “This discovery adds an important clue for understanding why there is a difference in the expected life span between men and women.”

On average women live 5 to 10 years longer than their male counterpart.

The added lifetime of a woman stems from the absence of male sex hormones – which the study says is the culprit in reducing a man’s life span.

Castration was a common option for boys who wanted early access to the palace. Once grown, they were allowed to maintain an adopted family.

The researches first proposed that it was perhaps the access to the palace that granted them the boost in longevity but in studying other palace officials, such as royal family members and rulers, it was found that most had an average lifespan of only 45 years old.

In addition, eunuchs were often outside of the palace. Away from any possible benefits held there.

The rate of centenarian occurrence in developed countries is still far below that of the Korean eunuchs, which is roughly 130 times higher.

All of the findings were published in Current Biology, where the researchers said that some clues to life extension might be found in their results.