During the past two decades, testosterone levels in American men have rapidly declined.
This information comes from a long-term prospective study that evaluated changes in serum testosterone on a population-wide basis.
The study was published in the Journal of Clinical Endocrinology and Metabolism.
“The interesting thing we discovered was that, on average, when we measured the testosterone in the blood of a 60-year-old in 1989 it was higher than that in a different 60-year-old measured in 1995,” said Thomas Travison, PhD, of the New England Research Institutes, Watertown, Mass. “We observed the same phenomenon over a wide range of ages.”
At baseline, the median serum testosterone level was 501 ng/d; at the first follow-up it was 435 ng/dL and at the second follow-up it was 391 ng/dL.
The decline was age-independent. “It is a little troubling,” Travison said. “The average differences are not very large, but they are big enough and occurring over a short enough time period to be the cause of some concern.”
These demonstrated population-level declines are greater than the cross-sectional declines typically associated with age, according to the researchers.
So American men really are becoming more physiologically pussified, emasculated, manboobed and womanish. And this hormonal change is expressing itself psychologically. Cf., John Scalzi.
The million dollar question: Why?
“This population-level decline in testosterone concentrations in men is not explained fully by the usual suspects: increasing BMI and prevalence of obesity, certain other co-morbid conditions or decreasing incidence of smoking. Although the analysis by Travison et al did reveal significant age-related increases in adiposity and medication use and a welcome decline in smoking, the age-matched decline in testosterone concentrations persisted even after adjusting for these variables,” Shalender Bhasin, MD, of the section
of endocrinology, diabetes, and nutrition, Boston University School of Medicine, wrote in an accompanying editorial.
He voiced concern over the decline and its public health impact on American men.
“This magnitude of change during such a short period is disquieting,” Bhasin wrote. “Although increasing adiposity and lifestyle factors that were recorded in the [Massachusetts Male Aging Study] could not account for the secular trends in testosterone level, it is possible that other lifestyle factors, such as increasing use of tight-fitting underwear, increasing room temperatures in American homes and offices during the past three decades, decreased physical activity with increased body mass indices and decreased smoking could have contributed to the declining testosterone levels in men.”
Whatever the actual cause, it doesn’t change the fact that men are seeing a drop in testosterone levels across the board. Maybe men should consider taking action to correct this generational drop.