In the long list of positive health outcomes associated with the Mediterranean diet — from bone health to heart health to mental health — a recent evidence review out of Australia adds yet another potential reason to cut down on red meat or add a couple of tablespoons of olive oil to a salad: improved fertility.
The recent study, published in the journal Nutrients, found that people who adhered to an anti-inflammatory diet such as the Mediterranean diet — which is mostly plant-based and avoidant of highly processed foods or ones with added sugars — had better outcomes with pregnancy and artificial reproductive technology.
“It’s not a particular food — it's the whole dietary pattern,” says study author Evangeline Mantzioris, Ph.D., a researcher on the study and program director of nutrition and food sciences at the University of South Australia. “This dietary pattern that is low in animal and processed foods shows us that you can reduce the chronic inflammation that occurs in the body — and chronic inflammation does have an impact on many aspects of fertility.”
For example, the researchers found that men who adhered to diets high in anti-inflammatory foods prevalent in the Mediterranean diet — such as whole grains, fruits, vegetables, legumes, nuts, and fish — had a higher sperm count and better sperm mobility compared to men who did not.
Among women, this diet was linked to more regular menstruation, higher embryo quality, higher likelihood of live birth, and lower risk of conditions that reduce the chance of getting pregnant, such as endometriosis and polycystic ovarian syndrome (PCOS).
Together, these outcomes in men and women influence the rate of success of assisted reproductive technology, such as in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI).
The improved fertility outcomes highlighted in this study are thought to be linked to the anti-inflammatory nature of the foods included in the Mediterranean diet and similar anti-inflammatory diets. Highly processed foods, high quantities of red meat, and foods with many added sugars have been linked to weight gain, inflammation, and chronic diseases such as diabetes and heart disease. Along with exercise and other lifestyle changes, such as reducing stress, healthy diets can reduce the chances of these diseases, in part because they’re rich in flavonoids, antioxidants, and other nutrients that reduce inflammation.
But more research directly linking dietary patterns to the success of these fertility treatments is needed. It’s possible that people who follow the Mediterranean diet are more likely to engage in other healthy practices such as exercise, so the researchers can’t be sure whether this way of eating is directly responsible for the improved fertility results. “Until you do this in an experimental study, you can’t say it is cause and effect,” Mantzioris says.
Still, as a “no-risk” intervention, changing dietary patterns may be an appealing option to families who have already tried IVF without success.
And besides the positive associations found with fertility, switching to a Mediterranean diet can also set an example for children later on and promote healthy diets for generations down the line, Mantzioris adds.
“These changes couples and expectant dads can do, it's not just for getting through the pregnancy successfully. It's also about providing the best outcomes for your children,” Mantzioris says. “If we keep remembering that our body is made up entirely of the food we eat, I think then you can start to realize how important a good and healthy diet is, and how setting those up for the family later on is important for the kids.”