Intermittent Fasting May Cause Fertility Problems, Says Study

Intermittent fasting, a diet that calls for restricting one's food consumption to certain hours of the day, can reportedly influence women's fertility.

A study conducted on fish models showed intermittent fasting disproportionately affects males and females. The study was focused on the zebrafish models because humans and the species are very similar on the genetic level.

The findings of the study were published in Proceedings of the Royal Society: Biological Sciences.

While on the diet, females experienced a drop in egg and offspring quality. The male sperm quality was also affected during the course of the diet.

"Time-restricted fasting is an eating pattern where people limit their food consumption to certain hours of the day. It's a popular health and fitness trend and people are doing it to lose weight and improve their health. But the way organisms respond to food shortages can affect the quality of eggs and sperm, and such effects could potentially continue after the end of the fasting period. We wanted to find out more about how these sorts of diets can affect fertility in a popular model organism," Prof Alexei Maklakov, from UEA's School of Biological Sciences, said in a news release.

The research team ran in-depth research to find out what happened when the body was provided with food after a period of fasting. They measured how the food components were split to serve the dual purpose of maintaining the body and sperm or egg production, as well as the quality of the resulting offspring, Phys.org reported.

"What we found is that time-restricted fasting affects reproduction differently in males and females. Once the fish returned to their normal feeding schedule, females increased the number of offspring they produced at the cost of egg quality resulting in reduced quality of offspring. The quality of male sperm also decreased," said Dr. Edward Ivimey-Cook, from UEA's School of Biological Sciences. "These findings underscore the importance of considering not just the effect of fasting on body maintenance but also on the production of eggs and sperm."

"Importantly, some of the negative effects on eggs and sperm quality can be seen after the animals returned to their normal levels of food consumption following time-restricted fasting. More research is needed to understand how long it takes for sperm and egg quality to return back to normal after the period of fasting."