Diet and sperm quality

Two recent studies examined the relationship between diet and semen quality - so be careful with full-fat dairy and carbs if you want to optimise your fertility.

Using data from the Rochester Young Men’s study, the first paper looked at the impact of dairy intake on sperm. This paper found that as dairy intake increased, semen quality declined. The relationship was even stronger as more full-fat dairy products were consumed. Increased consumption of full-fat dairy products was associated with lower sperm motility and concentration. Another study used the same database to examine the relationship of carbohydrate consumption and semen quality. Here they found that increased glycemic load, an index which summarised amount and quality of carbohydrates in the diet, was associated with a decline in sperm concentration in young men.

Two studies took a look at nutrition and its impact on patients undergoing IVF. In the first, patients were asked to do a dietary log and the data was analysed for nutritional content. They found that patients eating more proteins and fewer carbohydrates had higher rates of fertilised eggs developing to the blastocyst stage and higher pregnancy rates. In the second study, the same team took patients who had undergone IVF but had poor development of the fertilised eggs to the blastocyst stage and asked them to do a three-day nutrition log. They were then counselled on how to increase their protein intake and decrease their carbohydrate intake for 2 months before attempting another IVF cycle. In their next cycle, following the nutrition change, the blastocyst formation increased from 19% to 45% and the pregnancy rate went from 17% to 83%.

“These studies are most intriguing and demonstrate how little we know about the effects of micronutrients in our diets on various aspects of reproduction. They demonstrate a field wide open for future research and beg questions such as whether, for example, it is carbohydrates in general or the inflammatory effects of gluten in grain carbohydrates that are deleterious to IVF outcomes,” said Richard Reindollar, MD, Vice-President of the American Society for Reproductive Medicine.

The research was presented at the 68th Annual Meeting of the American Society for Reproductive Medicine.