Low-fat diets may be risky for men, but many questions remain

A study recently published in the Journal of Urology reports that low-fat diets may cause a decrease in testosterone levels in men. The findings were based on an analysis of data on 3,100 men who participated in the NHANES study. After accounting for other factors, the study found that low-fat diets in particular were 'significantly' linked to low serum testosterone levels.

Based on the NHANES data, around 14-percent of the 3,100 men reported eating a low-fat diet compared to the approximately 24-percent of men who ate the Mediterranean diet. Few participants met the criteria for low-carb diets, meaning that diet category wasn't included in this study.

Though the serum testosterone levels among men in both diet groups were found to be low, only the low-fat diet group was ultimately linked to low testosterone levels after accounting for other potential factors. The low levels were in comparison to the levels found in men who ate an unrestricted diet.

Avoiding a low-fat diet may not be ideal for all men, however. Reducing dietary fat comes with its own benefits for men who are overweight or obese, according to the researchers — benefits that may outweigh the downsides of slightly lower testosterone levels.

The researchers say that men who are a normal weight may want to avoid low-fat diets as part of an overall lifestyle change intended to increase serum testosterone levels. In addition to diet, these levels can be influenced by things like exercise. At this point in time, there's no 'best' diet recommendation for men suffering from low testosterone levels, according to the study.