Beef
You've probably read plenty of stories about the risks of eating chicken. But the most important protein to buy organic may well be beef. "Research suggests a strong connection between some of the hormones given to cattle and cancer in humans, particularly breast cancer," says Samuel Epstein, M.D., professor emeritus of environmental and occupational medicine at the University of Illinois at Chicago School of Public Health.
Specifically, the concern is that the estrogen-like agents used on cattle could increase your cancer risk, adds Ted Schettler, M.D., science director at the Science and Environmental Health Network.
Though there are strong regulations about the use of hormones in cattle, "not all beef producers are following those regulations strictly, and some studies continue to find hormone residue in cattle," Dr. Schettler says.
When you buy beef that's been certified organic by the United States Department of Agriculture (USDA), you're not only cutting out those hormones, you're also avoiding the massive doses of antibiotics cows typically receive, which the USDA says may lead to the development of antibiotic-resistant bacteria in people.
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