Another day, another headline about something that may (or may not) affect fertility. If you’re in the throes of trying to conceive, we understand how this goes: You read and analyze and hold on to every piece of information that comes your way. You do your very, very best to reconfigure your lifestyle so that everything you eat or drink or do best aligns with recommendations from the ever-evolving body of research surrounding reproductive health. Maybe you even do this at the expense of your mental and physical health — because there’s a lot of information out there, but not a lot of clarity surrounding so much of that information. Let’s take the recent headlines about intermittent fasting’s effect on fertility, for example.
Intermittent Fasting and Infertility
You may have heard that a study from the University of East Anglia found that time-restricted eating, a common form of intermittent fasting, can negatively affect the quality of both sperm and eggs. Maybe you’re a big fan of time-restricted eating, which involves consuming your calories within a specific window of time through the day, and felt alarmed by this news. Maybe you’ve even stopped this eating plan, or perhaps you’re panicking that a history of time-restricted eating could have caused irreversible damage to your fertility.
If so, take a deep breath: While this study is interesting for sure, it should be taken with a grain of salt. For one thing, the study was actually conducted on zebrafish, not humans. And, according to one expert, results found in studies of animals don’t always pan out in humans.
“This is an interesting study, however studies in other species often do not translate to human fertility,” says James Nodler, MD, reproductive endocrinologist and site director for the CCRM Houston Medical Center.
With that being said, Dr. Nodler does believe there could be a similar effect in humans. As for whether or not he’d recommend intermittent fasting for people who are looking to conceive? It’s a ‘no’ from Dr. Nodler, who is a fan of a different approach to nutrition for those who are hoping to grow their families.
Fertility Diet: It's All About Balance
“I recommend a balanced diet following the Mediterranean model with half of the plate being vegetables with every meal, a quarter of the plate being lean protein, and a quarter of the plate whole grains with any meal,” he adds. “We try to limit red meat and pork, and eat more fish or plant-based proteins like beans, lentils, nut seeds, and tofu.”
Part of time-restricted eating’s effect could come down to why someone is following this eating plan. For example, if someone is doing it for weight loss purposes — particularly in an attempt to boost their fertility by losing weight — it may not be the best plan.
“We know that being overweight or obese can increase [the] likelihood of infertility,” says Dr. Nodler. “Also, studies in humans have shown that intermittent fasting is not effective for long-term weight loss.”
With that being said, weight loss is not the only reason someone may be interested in time-restricted eating. If you’re a fan of it and find it works well for your body and lifestyle, there’s no hard evidence to suggest it will affect human fertility — so don’t feel like you absolutely need to change your approach or fear that a history of time-restricted eating has irrevocably damaged your odds of getting pregnant.
Ultimately, these findings don’t give us any real concrete answers about how time-restricted eating will affect fertility in humans. So file this under: Information that may be worth considering, but ultimately doesn’t need to inform your decisions or cause any additional stress.
The bottom line? If you love intermittent fasting (my hangry self could never, but you do you!) and you don’t want to give it up — that’s probably just fine. With that being said, you may want to chat with your doctor about whether or not it’s a good option for you personally.
Dr. Nodler agrees that when it comes to determining how these findings will translate to humans, there’s no clear-cut answer — yet. “This is an interesting study, however, animal models often don’t translate directly to human fertility,” he says. “I think that this is a good reminder to maintain healthy nutrition while trying for pregnancy and in pregnancy.”
Zara Hanawalt is a freelance journalist and mom of twins. She's written for outlets like Parents, Marie Claire, Elle, Cosmopolitan, Motherly, and many others. In her (admittedly limited!) free time, she enjoys cooking, reading, trying new restaurants, and traveling with her family.