DL: Are processed foods linked to infertility?

VM: Processed foods are filled with exactly the wrong kinds of carbohydrates and fats. The carbs are high on the glycemic index, which bumps up blood sugar, which in turn spikes insulin. Elevated insulin reduces a circulating protein called sex hormone–binding globulin (SHBG). SHBG’s task is just what its name implies: It binds estrogen, progesterone, and testosterone so that only small amounts circulate in the blood in the free or active form. Of all these sex hormones, SHBG has a preference for binding testosterone; so less SHBG means more unbound testosterone in the bloodstream, altering the overall hormonal balance to be more male dominant, which in turn can make it harder to get pregnant.

Many processed foods also contain trans fat, which raises the body’s inflammation levels—a fertility zapper—and increases insulin resistance, which leads the pancreas to secrete more insulin.

Avoid soda, too. In Harvard’s Nurses Health Study II, soda intake—including caffeinated, noncaffeinated, diet, and sugary versions—correlated to reduced fertility.