 Sexual selection may have also played a role in penis size. According to the best available science, three quarters of women find both penile length and girth somewhat or very important. What does this have to do with diet? Phthalates. Phthalates are chemical compounds that are used in a wide range of consumer products, including pesticides, paints, PVC plastic. However, the contribution of dietary intake to phthalate exposure has not been well-defined until now. But what's the problem with phthalate exposure? Effects on sexual health and development have been observed in recent human studies. We've known phthalates affect the genital development of lab rats, but for the first time ever, human data has been published. Simple study, they measured the levels of phthalates flowing through the bodies of pregnant women, and then later measured the size and characteristics of their infant son's genitalia after birth, between ages two months to three years. The women who had the most phthalate exposure had up to 10 times the odds of giving birth to sons with one or both testicles and completely descended. Their scrotum characterized as small and or not distinct from surrounding tissue, and a significant smaller penile volume, a measure of penis size taking into account both length and girth. In other words, the more phthalates pregnant women are exposed to the increased likelihood of testicular maldescent, a small and indistinct scrotum, and smaller penis size. They conclude, these changes in male infants associated with prenatal exposure to some of the same phthalate metabolites that cause similar alterations in male rodents suggest that commonly used phthalates may under-virialize humans as well. So what foods should pregnant women stay away from to avoid the phthalate-related syndrome of incomplete virialization? The urine levels of thousands of Americans all across the country were measured along with their diets to find out which food most significantly associated with phthalate body burden. They looked at dairy, they looked at eggs, fish, fruit, poultry, potatoes, tomatoes, vegetables in general, and red meat. Statistically, the most significant result in their analysis was poultry consumption. So, for example, in one analysis, while total dairy consumption was significantly associated with one of the phthalate chemicals called MCPP and eggs with another MEHP, poultry consumption was associated with a significant predictor of levels of all the individual DEHP metabolites, MEHP, MEAHP, OHP, MECCP, etc., etc., etc. Suggesting that an increase of 1 ounce of poultry per day is associated with an increase in one of the phthalate metabolite levels of approximately 5.7%, a single chicken breast is nearly 8 ounces. Maybe it was just leaching into the meat from the plastic wrap packaging? Probably not. The finding that egg consumption is significantly associated with levels of phthalates too suggests that chickens themselves may be contaminated and that food is not being contaminated just through packaging and processing. So, if there is one thing pregnant women may want to avoid during pregnancy to protect their son's normal development, it would be to avoid poultry.