Obesity Lowers Testosterone Levels // Waist circumference is the strongest single predictor of developing Low-T

This Harvard paper from 2011 tells us:

“Obesity lowers testosterone levels. For example, a 2007 study of 1,667 men ages 40 and above found that each one-point increase in BMI was associated with a 2% decrease in testosterone. In addition, a 2008 study of 1,862 men ages 30 and above found that waist circumference was an even stronger predictor of low testosterone levels than BMI. A four-inch increase in waist size increased a man’s odds of having a low testosterone level by 75%; for comparison, 10 years of aging increased the odds by only 36%. All in all, waist circumference was the strongest single predictor of developing symptoms of testosterone deficiency.”

Source: Obesity: Unhealthy and Unmanly
^{https://www.health.harvard.edu/mens-health/obesity-unhealthy-and-unmanly}

And don’t forget.. body fat converts testosterone into estrogen..

“Body fat contains aromatase, an enzyme that converts testosterone into estrogens, the main sex hormones in women. Having extra estrogens floating around your system triggers your body to slow its production of testosterone. And the less testosterone you make, the more belly fat you accumulate and the more estrogens you spew.”

Source: Men’s Health: 3 Steps to More Testosterone
^{https://www.menshealth.com/weight-loss/a19537203/improve-your-testosterone}