Instructor, Harvard Medical School
Associate Professor, Harvard School of Public Health
Director, Male Fertility, Stanford School of Medicine
The degree to which maintaining a healthy diet improves both partner’s ability to conceive is astonishing. Here we’ll take a hard look at how adhering to a traditionally healthy diet improves fertility and, in the next chapter, we’ll contrast that to rates of success amongst couples that consume high levels of fast food. Unfortunately, a lot of fad diets (keto, paleo) undermine a woman’s ability to conceive - we’ll cover these closely in our video tutorial.
Amongst women trying to conceive naturally, Spanish women who most closely adhered to a Mediterranean diet (high consumption of fruits, vegetables, legumes, fish and low consumption of non-fish meat) were 46% more likely to conceive than women who more loosely adhered to the diet.
The same held true amongst women undergoing IVF, where this phenomenon was documented in 100+ Dutch women. Those who stuck with a Mediterranean diet were 40% more likely to conceive during an IVF cycle than women who had the loosest adherence to the diet.
The same is true for men, as those who most loosely adhered to a Mediterranean diet were far more likely to record low sperm counts, motility, or rates of abnormal morphology.
Another diet with interesting data as it relates to IVF outcomes is the “profertility diet,” which tends to emphasize seafood over meat, low pesticide fruit over high pesticide fruit (see here), a reduction in soy or dairy intake and healthy levels of supplemental folic acid, B12, and Vitamin D.
As you can see below, women with the highest adherence (pre-treatment) to the profertility diet notched higher rates of IVF embryo implantation, pregnancy and live birth.
On the other end of the spectrum, women who consume a fast food diet four or more times per week (a relatively low bar) are significantly more likely to have fertility issues (unable to conceive after 12 months of trying) compared to women who rarely eat fast food. Below you can see the varying levels of infertility based upon fast food consumption in over 5,000 women in a superb study run out of Australia. In the next lessons we’ll cover the effect that meat and fatty acids can have on fertility.