Low Fat Diets May Boost Male Fertility

Infertility affects about 15% of couples globally, according to W.H.O up to 25% of couples in developing countries are affected, the causes are varied but 20-30% of the problems are attributed to male factors alone. 

“There’s an assumption that ‘good’ fats and ‘bad’ fats perform as they’re described — but what’s surprising, is that it wasn’t the type of fat that mattered at all, as an equal amount of the good and bad fats significantly suppressed testosterone production,” said Lead researcher Dr. Karma Pearce from the University of South Australia.

This study tested individual nutrients and the effects may be different in the context of whole food dietary patterns, but previous work showed typical Western diets produced a 25% decrease in serum testosterone within an hour of eating with the levels remaining suppressed for up to 4 hours. 

“In this study we also found that consuming albumen — the protein in egg whites — increased testosterone levels, and did so by four-fold relative to fasting, while albumin, combined with the bad saturated fat somewhat ameliorated the effect of the bad fats on testosterone levels, providing another diet-based influencer of testosterone levels.”

8 types of diets were tested: meals comprised of polyunsaturated fats, monounsaturated fat, refined carbohydrates, whey, egg whites, and mixed meals of polyunsaturated fats and refined carbohydrates, polyunsaturated fats and egg whites, refined carbohydrates and egg whites, all with 4 blood tests and hormone analyses being taken before eating and then at every hour afterwards for 5 hours. 

The researchers say that this study is the first in a series needed to both support and enhance fertility; this study analyzes the effects of various dietary macronutrients on testosterone production but not sperm quality, and suggests the potential for diet to be negatively impacting sperm production and fertility that may be important to those trying to start a family. Next phase for the researchers will be to evaluate longer term effects of these nutrients on testosterone levels in the context of whole food dietary patterns. 

“It’s important to note that it’s still early days, and more research needs to be done, particularly at looking at the effect of these nutrients in the context of whole food dietary patterns over the longer-term,” Pearce said. “Over the Christmas period, for infertile men, and men with lower than normal testosterone levels, lowering the overall fat content and possibly increasing whey or adding egg whites may lead to improvements in testosterone levels over the shorter term.”