Why men should avoid low-fat diet

For many men diagnosed with testosterone deficiency, losing weight can help increase testosterone levels, say researchers, adding that, specifically a low-fat diet may be associated with a small but significant reduction in testosterone. “We found that men who adhered to a fat restrictive diet had lower serum testosterone than men on a nonrestrictive diet,” said study researcher Jake Fantus from University of Chicago in the US.

“However, the clinical significance of small differences in serum T across diets is unclear,” Fantus added.

For the study, published in the Journal of Urology, the research team analysed data on more than 3,100 men from a nationwide health study (the National Health and Nutrition Examination Survey, or NHANES).

All participants had available data on diet and serum testosterone level. Based on two-day diet history, 14.6 per cent of men met criteria for a low-fat diet, as defined by the American Heart Association (AHA).

Another 24.4 per cent of men followed a Mediterranean diet high in fruits, vegetables, and whole grains but low in animal protein and dairy products. Only a few men met criteria for the AHA low-carbohydrate diet, so this group was excluded from the analysis.

The average serum testosterone level was 435.5 ng/dL (nanograms per deciliter). According to the study, serum testosterone was lower in men on the two restrictive diets: average 411 ng/dL for those on a low-fat diet and 413 ng/dL for those on the Mediterranean diet.