|Losing weight and getting in shape can make you feel like Burt Reynolds circa 1978 too.|
The Annual Endocrine Society Meeting of 2012 is over and some interesting reports have been made that will be sure to interest Masters CrossFit, men who are trying to lose weight and the women who love them . . . or at least might find them hot (Dwyer et al. 2012). Being overweight or pre-diabetic can lower testosterone levels. That is not surprising, since fat cells produce an enzyme called aromatase. Aromatase converts testosterone to estrogen. Insulin resistance seems to slow production of testosterone. Diabetic, overweight men are probably getting hit from two different directions.
The men who participated in the study were part of a diabetes prevention program that had them either taking a placebo, taking a diabetes drug called Metformin, or increasing their exercise levels to 150 minutes a week and reducing caloric intake. All the men were pre-diabetic. Neither Metformin nor placebos had an effect on testosterone levels. Men on the workout and exercise program had a significant increase in testosterone at the end of the study. Effects were strongest in men who had the lowest testosterone at the start of the study. Men in the workout program lost an average of 17 pounds over the course of a year. Men who received the drug lost about 6 pounds, and men on the placebo did not lose weight.
Overweight also puts women (and men) at greater risk of breast cancer. Being overweight increases aromatase in breast tissue. Losing weight (if you are overweight) is important for women’s health as well.
Chen D, Zhao H, Coon JS 5th, Ono M, Pearson EK, & Bulun SE (2012). Weight gain increases human aromatase expression in mammary gland. Molecular and cellular endocrinology, 355 (1), 114-20 PMID: 22342815.