A Disturbing Trend: Testosterone Levels Falling Even Lower in Adolescent Males

Low testosterone levels seen in adolescent and young males when their levels should really be the highest in their lifetimes

The update on testosterone levels of young men in the United States for 2020 is in and it is not good news. A series of scientific studies were presented on May 15^th at the American Urological Association 2020 Virtual Experience press conference and they displayed some interesting, but disturbing, findings.

One of these studies involved 4,045 men (adolescents and young men) who were between the ages of 15 and 39 years. They all participated in the National Health and Nutrition Examination Surveys (NHANES) and had their total testosterone levels measured over the time period between 1999 and 2016. Total testosterone is a measure of how much testosterone there is in the blood in both free and bound forms. Most of the testosterone is attached to two different proteins: albumin and sex hormone-binding globulin (SHBG). Other testosterone molecules travel around free in the bloodstream.

Total Testosterone Levels Falling Over Time in Young Men

The results of the data analysis showed that total testosterone was significantly lower in the young men who were part of the 2011-2016 group when compared to the earlier group of 1999-2010. It appears that average total testosterone decreased over time from 605.39 ng/dL starting in 1999-2000 to 567.44, 424.96, 431.76 and 451.22 in the survey cycles 2003-2004, 2011-2012, 2013-2014 and 2015-2016, respectively. When these averages were compared, their differences were statistically significant.

The young men's body mass indexes (BMI) were also measured along with their total testosterone which was found to be independently associated with decreased testosterone levels. The average BMI rose from 25.83 kg/m² in 1999-2000 and by 2015-2016, the average was 27.96 kg/m². An interesting finding was that even in men who had a normal (18.5-24.9 kg/m²) and not an obese BMI, the testosterone levels dropped from 664.79 to 529.24 ng/dL.

What is Causing Lowered Testosterone Levels in Young Men?

One of the authors of the study, Soum D. Lokeshwar, MD, of the Yale School of Medicine, thinks he has part of the answer: “The biggest and most seemingly obvious may be the rise in obesity and BMI in young men.” We've all noticed the increased incidence of obesity among our peers over the past ten years or so, but the Centers for Disease Control and Prevention reported that the prevalence of obesity in the United States went from 13.9% in 1999 to 18.5% in 2015. That is quite a jump!

In other studies, there was a correlation found between increased fat and increased estrogen production in men, leading to decreased testosterone levels. Therefore, just having a higher body fat percentage, but still a normal BMI, can lower testosterone levels in men. “Even in men with a normal BMI, body fat percentage may have increased on a national scale, which may be due to this decrease in physical activity,” stated Lokeshwar.

Health Issues Caused by Low Testosterone

Increasing obesity and lowered testosterone levels can be a recipe for cancer in young men, the worst possible scenario. Other adverse side effects of low testosterone include:

• decreased libido
• erectile dysfunction
• depression
• decreased muscle mass
• low self-esteem
• poor quality of life

Thankfully, low testosterone is easily treatable with testosterone replacement therapy (TRT), healthy eating and regular exercise. However, Dr. Lokeshwar points out that, “testosterone levels in [young men] are utilized as the benchmark normal levels for testosterone. This is very scary because generally when we think of normal values of testosterone, we treat based on this age group. This may ultimately lead to the undertreatment of testosterone deficiency...”

Physical Activity and Testosterone Levels

Richard Fantus, MD, from the University of Chicago, presented a study looking at the effect of physical activity on serum testosterone levels. He and his collaborators also used NHANES data but from 2011-2016 and from 7,597 men. The subjects were divided into three cohorts: physical activity less-than-recommended (<500 MET minutes a week), recommended (500-1,000 MET minutes a week) and greater-than-recommended (>1,000 MET minutes a week).

Overall, low testosterone (<300 ng/dL) was detected in 2,201 men or 29%. Of the men in the greater-than-recommended cohort demonstrated significantly decreased odds of exhibiting low testosterone (37%) when compared to the less-than-recommended cohort. Interestingly, when bringing BMI into the equation, researchers found that the association of greater-than-recommended activity with a reduced risk of low testosterone was only found among obese men.

Dr. Fantus concludes that, “it's incredibly important to really counsel the obese population, as exercise independent of weight loss may show additional benefits.”

Testosterone Replacement Therapy Programs

At our men's testosterone clinic, we specialize in treating men with low testosterone both naturally and with hormone therapy. With such trends in testosterone levels seen in our younger population, it is a good idea to get your testosterone levels checked regularly. At our clinic, it is easy to set up an appointment for a comprehensive blood test that measures both total and free testosterone levels.

If you find yourself suffering from the conditions listed above, we can set you up with a natural TRT program or one using testosterone injections, creams or gels, depending on the severity. Both types of programs include a nutrition and exercise plan as well. As demonstrated by the University of Chicago study, exercise is imperative in controlling testosterone levels, especially in obese men. It is never too late to change!

References

Renal and Urology News

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