A new report released Monday claims the science is clear: Eating too much meat is bad for your health.
The so-called Meat Eater's Guide, compiled by the Environmental Working Group, is generating buzz for its "cradle-to-grave" look at the environmental impact of 20 popular types of meat, dairy and vegetable proteins. But it also emphasizes the potential health impact of eating too much meat, recommending that people cut back to decrease their risk of heart disease and certain cancers.
"The goal is to really make this information accessible to consumers," said Kari Hamerschlag, an agriculture analyst with the research and advocacy group. "On the health side, we really pulled together all of the information and tried to make it as clear as possible that there's not just one reason to limit meat consumption; there are a whole host of reasons."
The report, which weaves together statistics from various earlier studies, allows that meat can be an important source of protein and vitamins when eaten in moderation. But in the U.S., moderation may be a problem. The report cites data from the United Nations Food and Agriculture Organization suggesting that Americans consume almost 60 percent more meat than their European counterparts, and four times more than in many developing countries. And much of that meat is either red or processed.
The health effects of this, the EWG report claims, are myriad: A 2009 report from the National Cancer Institute found that people who ate the most red meat -- which can have high levels of cholesterol-rising saturated fat -- were 27 percent more likely to die of heart disease. That same report also found serious meat eaters were 20 percent more likely to die of cancer than those who consumed the least amount of meat.
The American Meat Institute, a trade association representing companies that process most of the red meat and turkey in the United States, issued a statement saying that "the total body of evidence clearly demonstrates that meat is a healthy part of a balanced diet," adding that the report oversimplifies many of the health issues.
Indeed, Marjorie McCullough, Sc.D., strategic director of nutritional epidemiology with the American Cancer Institute, cautioned that the link between high meat consumption and a broad range of cancers -- including prostate and pancreatic -- is possible, but not entirely clear. However, she said there is a consistent association between red and processed meats and a risk of colon cancer. Scientists have hypothesized that the nitrates in processed meats are a possible culprit, as are the chemicals formed when red meat is cooked at high temperatures.
"What people always ask next, is 'what is the magic number?' in terms of servings of meat to aim for," McCullough said. "Unfortunately, there is no real magic number. I generally say that if you currently eat red meat, you should cut back by half." (The American Cancer Society recommends that people limit their intake of red and processed meats, but also does not provide an exact figure.)
The EWG report calls for people to limit their intake of meat by enjoying "Meatless Mondays," and when they do eat it, opting for meat that comes from grass-fed, certified organic and pasture-raised animals. The American Institute for Cancer Research and the American Dietetic Association recommend limiting red meat consumption to 18 ounces per week -- a little more than a pound.
Others say the simplest move health-wise is simply increasing consumption of fruits and vegetables in line with the My Plate recommendations, leaving less room for other foods, like meat.
"If you focus on filling up on fruits and veggies, so they're at least half your plate, you're not going to have a lot of room left to even eat all that meat," said Joan Salge Blake, R.D., a spokesperson for the American Dietetic Association. "The biggest thing is just getting down the amount we eat."