Low Fat Diets Lower Testosterone Levels in Men
A systematic review and meta-analysis by The Journal of Steroid Biochemistry and Molecular Biology examined the effect of low-fat diets on testosterone levels in men. The authors conducted a comprehensive literature search to identify randomized controlled trials that prescribed a low-fat diet intervention and measured testosterone levels in adult men before and after the diet.
The analysis included 28 eligible studies with a total of 1,954 men across the different study populations. The authors found that:
– Low-fat diet interventions were associated with a significant decrease in total testosterone levels compared to baseline/control groups.
– The decrease in testosterone levels was larger in studies with greater reductions in dietary fat intake.
– Studies with a higher percentage of calories from fat at baseline tended to show greater decreases in testosterone when put on a low-fat diet.
– The effect of low-fat diets reducing testosterone levels remained significant even after adjusting for changes in body weight, suggesting dietary fat intake itself impacts testosterone production.
The authors propose some potential mechanisms that could explain why low-fat diets lower testosterone, including reducing cholesterol availability for steroidogenesis and altering hormone-binding proteins.
They conclude that adopting a low-fat diet leads to a significant decrease in circulating testosterone concentrations in men. This effect should be considered when recommending low-fat dietary patterns, especially for men already at risk of hypogonadism or testosterone deficiency.
Overall, this meta-analysis provides evidence that low-fat diet interventions can have an unfavorable impact on testosterone levels in the male population studied. Monitoring testosterone during low-fat diets may be warranted based on these findings.
