Testosterone levels falling 1% every year

First it was sperm levels, now it's testosterone. A new study has found a 'substantial' drop in the testosterone levels of men in the USA since the 1980s. Although the reasons for the decline remain unclear, the trend is not related to age.

The average levels of the male hormone are dropped by 1% a year between 1987 and 2002 which means that a man would have 15% less testosterone today than a man of the same age in1987.

The result, inevitabaly is that more men have testosterone levels that are belwo 'normal'.

'The entire male population is shifting somewhat downward we think,' Dr. Thomas Travison and colleagues from the New England Research Institutes in Watertown, Massachusetts told Reuters.

Rising obesity as well as the sharp decline in cigarette smoking might help explain their findings, given that testosterone levels are lower among overweight people and smoking increases testosterone levels. However, these factors could account for only a tiny part of the difference.

It's likely that some sort of environmental exposure is responsible for the testosterone decline, Travison said, although he said attempting to explain what this might be based on the current findings would be 'pure conjecture.'

'Like most things that are complex, it's likely that there is no one cause,' he said.

More to the point, does it matter? What do you think?