Testosterone levels are still falling in young men, quite significantly. It's a good time to be in the testosterone replacement business. From the article:
In an analysis of data from 4045 adolescent and young men aged 15 to 39 years who participated in the National Health and Nutrition Examination Surveys (NHANES) and had their total testosterone (TT) levels measured during 1999-2016, TT was significantly lower among those in the later (2011-2016) compared with earlier (1999-2000) survey cycles. Mean TT decreased over time from 605.39 ng/dL in 1999-2000 to 567.44, 424.96, 431.76, and 451.22 ng/dL in 2003-2004, 2011-2012, 2013-2014, and 2015-2016, respectively, The declining trend was statistically significant.
Elevated body mass index (BMI) was significantly and independently associated with decreased TT levels, with mean BMI rising from 25.83 kg/m2 in 1999-2000 to 27.21, 27.12, 27.81, 27.96 kg/m2 in 1999-2000, 2003-2004, 2011-2012, 2013-2014 and 2015-2016, respectively. Even in men with normal BMI (18.5-24.9 kg/m2), TT levels declined from 664.79 to 529.24 ng/dL between 1999-2000 and 2015-2016.
In an analysis of data from 4045 adolescent and young men aged 15 to 39 years who participated in the National Health and Nutrition Examination Surveys (NHANES) and had their total testosterone (TT) levels measured during 1999-2016, TT was significantly lower among those in the later (2011-2016) compared with earlier (1999-2000) survey cycles. Mean TT decreased over time from 605.39 ng/dL in 1999-2000 to 567.44, 424.96, 431.76, and 451.22 ng/dL in 2003-2004, 2011-2012, 2013-2014, and 2015-2016, respectively, The declining trend was statistically significant.
Elevated body mass index (BMI) was significantly and independently associated with decreased TT levels, with mean BMI rising from 25.83 kg/m2 in 1999-2000 to 27.21, 27.12, 27.81, 27.96 kg/m2 in 1999-2000, 2003-2004, 2011-2012, 2013-2014 and 2015-2016, respectively. Even in men with normal BMI (18.5-24.9 kg/m2), TT levels declined from 664.79 to 529.24 ng/dL between 1999-2000 and 2015-2016.
