Pickles, Lettuce, Mayo … Hold the Estrogen continued...
It’s also long been known that breast cancer risk increases with higher lifetime exposure to estrogen. These facts have led many to question whether the continued use of synthetic estrogens in livestock is safe.
Recombinant bovine growth hormone (rBGH) is a different class of hormone that increases the amount of milk dairy cows produce. Some suggest that although rBGH itself appears safe, it increases the amount of other chemicals in the body that might cause cancer. So far, there’s no definitive proof one way or the other.
How much hormone is in a hamburger, and could it hurt you? The answer is, no one really knows. Studies show the added hormones do show up in beef and milk, pushing their estrogen and testosterone content to the high end of normal for cows. Whether that translates to increased risk for humans is the question.
“It really depends on how you look at the science,” Minowa tells WebMD. “Many industry-funded studies show no risk, but there are independent studies that suggest” a potential cancer risk from hormones in milk.
Hormone-treated meat has long been suspected of contributing to early puberty in children, although the link has not been proven. There’s no question that the age of puberty has been decreasing in the U.S. But some suggest that’s due to improved nutrition and health, not to second helpings of hormones in children’s diets.
The effects are very hard to study, experts say, because hormones are naturally present in both food and our bodies. Plus, the effects could be subtle and take years to show up.
The amount of hormone that enters a person’s bloodstream after eating hormone-treated meat is small compared with the amount of estrogen a person produces daily. However, even low levels of hormones can have strong effects on some body processes.
Responding to the lack of certainty, the European Union has banned all hormones in beef, and Japan, Canada, Australia, New Zealand, and the EU have banned rBGH. No major studies are under way in the U.S. to evaluate the safety of hormones in meat and milk.