Washington: Turns out, men's testosterone levels are largely determined by their environment during childhood.

A study led by Durham University suggests that men, who have a more challenging environment while growing up, for example, with lots of infectious diseases are likely to have lower testosterone levels in later life than those who spend their childhood in healthier environments. The researchers suggested that while analyzing risk profiles one may need to take a man's childhood environment into account, as high testosterone levels lead to an increased risk of prostate enlargement and cancer.

They also found that in environments where people are more exposed to diseases or poor nutrition, developing males direct energy towards survival at the cost of testosterone. Lead author of the study, Dr. Kesson Magid from Durham University's Department of Anthropology said, "A man's absolute levels of testosterone are unlikely to relate to their ethnicity or where they live as adults but instead reflect their surroundings when they were children."

Men with higher levels of testosterone are at greater risk of potentially adverse effects like increased muscle mass, increased risk of prostate diseases and higher aggression. Whereas, very low testosterone levels in men can include lack of energy, loss of libido and erectile dysfunction.

Co-author Professor Gillian Bentley from Durham University said, "Very high and very low testosterone levels can have implications for men's health and it could be important to know more about men's childhood circumstances to build a fuller picture of their risk factors for certain conditions or diseases."

Aspects of male reproductive function remain changeable into adolescence, up to the age of 19 and are more flexible in early rather than late childhood, according to the research.

The full findings are present in the Journal- Nature Ecology and Evolution.