The Endocrine Society's 94th Annual Meeting and Expo:
Hypogonadism Reversal in Overweight Men with Prediabetes
In obese men who have type 2 diabetes, testosterone levels are often lower than in age- and weight-matched controls. Previous studies have shown that an increase in insulin resistance is connected to a decrease in Leydig cell testosterone secretion; however, the causality of this relationship has not been extensively explored.
Research presented at The Endocrine Society’s 94th Annual Meeting addressed this question: how do weight loss and a decrease in insulin sensitivity impact serum testosterone levels?1
Using participants from the Diabetes Prevention Program (DPP), researchers assessed the following data: BMI, waist circumference, physical activity, insulin sensitivity, and reproductive hormone levels (testosterone and luteinizing hormone). These measurements were made at baseline and at 12 months.
Men who were able to participate in this study did not have a known diagnosis of hypogonadism, nor were they taking medications that could interference with testosterone. There were 891 men who met this criteria; their mean age was 53.9 ± 0.4years. The mean BMI was 31.9 ± 0.2 kg/m2.
As part of the DPP, the men had been randomized into 3 groups: lifestyle modification (n = 293), metformin (n = 305), or placebo (n = 293).
Did Testosterone Levels Change?
In the group randomized to lifestyle modification, there was a 15% increase in testosterone levels over the 12-month period (417 ± 8 ng/dL at baseline vs 460 ± 7 ng/dL at 12 months, p < 0.0001). In that same group, there was no change in luteinizing hormone.
At baseline, 20.4% of the men in the lifestyle group could be considered hypogonadal (testosterone levels < 300 ng/dL). After intervention, this decreased to 11.1% (p < 0.05)
In the 2 other treatment groups, however, testosterone levels did not change, nor did the prevalence of hypogonadism.
Looking at correlations, it was seen that the change in testosterone level was correlated with a change in body weight (r = -00.32, p < 0.0001), waist circumference (r = -0.13, p = 0.001), and insulin sensitivity (r = -.13, p < 0.0001).
Weight Loss Can Increase Testosterone Levels
Frances Hayes, MD, study co-author, noted, “Losing weight not only reduce the risk of prediabetic men progressing to diabetes but also appears to increase their body’s production of testosterone.”