Just one serving of meat a day may increase a woman’s risk of anovulatory infertility by 30% (or 50% in the case of poultry). Furthermore, the sex steroid hormones in meat and the endocrine-disrupting pollutant in fish may affect the development of male genital organs while still in the womb, consequently decreasing their fertility later in life.
Male infertility accounts for half of the 10%-15% of couples who have trouble conceiving. Evidence suggests soy protein does not affect male fertility. Soy may, however, decrease sperm concentration because it may increase total ejaculate volume, but has no effect on total sperm count. On the other hand, meat and cheese appear to lower sperm counts and semen quality on account of steroids, saturated fat, dioxins, and other pollutants in the meat supply, though omega-3’s (like those found in walnuts) appear to improve sperm vitality, movement, and shape. Vegetarian men were found to have higher sperm counts than fish eaters, most likely due to the xenoestrogens present in fish. Seafood might also affect male fertility by increasing radioactive polonium levels in semen, though more research still needs to be done to determine how much seafood must be consumed for the effects to become clinically relevant. Pregnant women and women planning to become pregnant may want to reduce their fish intake to less than what the FDA considers safe due to the mercury and other pollutants in fish, which can increase a person’s risk of developing diabetes. Women who eat eggs or meat are significantly more likely to develop gestational diabetes while pregnant.
Dairy is perhaps the richest source of estrogens in our diet, attributed to the fact that most milk these days comes from pregnant cows. These estrogens appear to lower testosterone levels in males while simultaneously upping their estrogen levels. But it’s not just dairy – animal protein in general appears to contribute to the recent trend of earlier onset puberty, whereas soy milk may help normalize development. The endocrine-disrupting industrial chemicals that build up in meat may be another cause for earlier sexual development. Monsanto’s Roundup may have hormonal effects, though the science on the topic is still clouded by industry bias.
Topic summary contributed by Selena.