The University of East Anglia has recently revealed through a new study that time-restricted fasting diets may have detrimental effects on fertility. The research, which focused on male and female zebrafish, discovered that reproduction was affected in varying ways for each gender. Notably, the study showed that certain negative impacts on eggs and sperm quality were observed even after the fish resumed their regular food intake levels.
The researchers emphasize that although the study was conducted on fish, the findings underscore the significance of not only examining the effects of fasting on weight and overall health but also on fertility. This suggests that time-restricted fasting diets may have implications for reproductive health in addition to their potential impacts on weight management and general well-being.
Professor Alexei Maklakov, a researcher from the University of East Anglia's School of Biological Sciences, explains that time-restricted fasting is a dietary pattern in which individuals restrict their food intake to specific time windows during the day. This practice has gained popularity as a health and fitness trend, with people adopting it for weight loss and improved health purposes.
“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.”
The research team studied zebrafish (Danio rerio) to find out what happens when individuals are exposed to food during and after a period of fasting. They measured how males and females allocate resources to body maintenance versus production and maintenance of sperm and eggs, and the quality of the resulting offspring.
Dr. Edward Ivimey-Cook, another researcher from the University of East Anglia's School of Biological Sciences, explains that the study revealed distinct differences in the effects of time-restricted fasting on reproduction between males and females. When the zebrafish returned to their regular feeding schedule after the fasting period, females increased the number of offspring they produced, but at the expense of egg quality, resulting in reduced quality of offspring. Additionally, the quality of male sperm also decreased as a result of time-restricted fasting. These findings suggest that fasting patterns can impact reproductive health differently in males and females, potentially affecting both the quantity and quality of offspring.
“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.” (PB/Newswise)