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Bacon has been called the gateway meat for its powers to lure vegetarians back to carnivorous habits. And who among us - at least, the carnivores - has not devoured a hotdog at a backyard barbeque? Well, a new study may scare you away from the grill. It comes from the Harvard School of Public Health, and it finds that people who eat lots of red meat has significantly higher risks of cancer, heart disease and premature death. NPR's Allison Aubrey has the story.
ALLISON AUBREY, BYLINE: If you're a meat lover, I promise the news is not as bad it may sound. Nowhere in the story is anyone going to tell you that you must become a vegetarian. But if you consume red meat daily, as most of the volunteers in the study did - maybe bacon for breakfast and a burger for dinner - there's overwhelming consensus among nutrition researchers, including Margie McCullough, that this is too much.
MARGIE MCCULLOUGH: That's right. Absolutely, that would be considered too much. The evidence is convincing that red meat increases the risk of cancer.
AUBREY: McCullough is an epidemiologist with the American Cancer Society and she says the new study published today in the Archives of Internal Medicine adds to the evidence about how much risk comes with two servings or seven to eight ounces of red meat daily.
MCCULLOUGH: It's associated with approximately 40 percent increased risk of colorectal cancer and, as this study shows, about a 30 percent increased risk of death.
AUBREY: Now, we all have to eat something and we all end up dying, eventually, so lots of us want to know: is there a safe amount of red meat to consume if we don't want to add to our risks of these diseases? Frank Hu of the Harvard School of Public Health, who is the author of the new study, says he thinks so.
FRANK HU: Yeah. We are not talking about a vegetarian diet.
AUBREY: Who explains, based on his findings, he thinks that a half serving a day or, put another way, two to three servings a week, is what meat eaters could feel comfortable with.
HU: A moderate consumption, for example, one serving every other day, I think is fine.
AUBREY: Now, Hu changes his tune when it comes to processed meats, particularly hot dogs and bacon. These meats, he says, he's gotten completely out of his diet because his study and others suggest that they elevate the risks of cancer above and beyond that of unprocessed red meats.
HU: I mean, as a researcher, I always practice what I preach.
AUBREY: It's not clear why processed meats appear to be riskier. One theory is that the iron in meat works as a catalyst to turn nitrites, which are added preservatives, into a particular kind of carcinogen in the body. It's also possible that because hot dogs are often grilled, the direct access to the flame could be an issue.
Either way, the American Meat Institute Foundation disagrees with the findings that processed meats elevate the risk of cancer.
BETSY BOOREN: I don't think there are a lot of risks associated with those processes. First of all, they're all made from meat, which is needed in the body.
AUBREY: Betsey Booren is director of scientific affairs for the American Meat Institute Foundation. She says, after reviewing the new paper from the Harvard researchers, she finds it to be flawed in both its methodology and its conclusions. She points out that the findings come from analyzing food frequency questionnaires, basically surveys, asking volunteers to recall what they ate and then researchers keep track of the volunteers over decades to see if they develop particular diseases. It's not a very precise method and researchers have long acknowledged this, but it's long been considered the best way to pick up associations between diet and disease.
Booren says, given this methodology, it's unfair to single out meat when there are so many other factors that increase the risk of heart disease and cancer.
BOOREN: It's not one factor that raises your risk for disease. It could be your genetics and obesity and it's over-consuming all foods, not just meat products.
AUBREY: So maybe the meat scientists and the Harvard researchers do have something in common. Though they clearly disagree on risks, both seem to be making the case for moderation.
Allison Aubrey, NPR News.