Dr. Gabe Mirkin's Fitness and Health e-Zine
Dr. Gabe Mirkin's Fitness and Health e-Zine
October 13, 2019
Red Meat Associated with Heart Attacks, Certain Cancers, and Premature Death
Don't believe the recent headlines suggesting that people can continue to eat their usual amounts of meat without suffering any increase in risk for illness or premature death. These news stories are based on articles in the Annals of Internal Medicine (September 30, 2019), that have caused many members of the scientific community to respond with horror and disbelief. Eating either meat or sugar increases disease risk and shortens lives. The authors summarized studies of meat reduction in populations that ate more sugar and other refined carbohydrates instead, so they showed that you gain nothing by substituting one harmful food, sugar, for another, meat. The authors did not analyze studies in which healthful foods, such as vegetables, beans, nuts and fruits, were substituted for meat.
Thirteen prominent researchers on the health risks of eating meat, including one of the authors of these new papers, wrote to the Annals' editor-in-chief, Christine Laine, MD, MPH, requesting a delay in publication of the papers. This group included Harvard's Walter Willett; David Katz of the True Health Initiative; Dean Ornish, MD, longtime researcher on the link between nutrition and heart attacks; Kim Williams, MD, former American College of Cardiology president; and former U.S. Surgeon General Richard Carmona, MD. Severe criticisms of the studies exonerating meat have already been issued by The American Heart Association, the American Cancer Society, the Harvard T.H. Chan School of Public Health and many other groups. The Harvard group warned that these recommendations "harm the credibility of nutrition science and erode public trust in scientific research." The Physicians Committee for Responsible Medicine filed a petition against the journal with the Federal Trade Commission.
Dr. Frank Sacks, past chair of the American Heart Association's nutrition committee, called the research "fatally flawed." Dr. Frank Hu, chairman of Harvard's Department of Nutrition, called it "irresponsible and unethical," and said that the consistency of the conclusions of many studies over many years gives credibility to the association of red meat with heart attacks, cancers and premature death. There was disagreement about the safety of meat even among the authors of these papers, and three of the 14 authors concluded that people should reduce their intake of meat.
The lead author of this analysis of meat, Bradley Johnston, did not disclose that he had written a similar report exonerating sugar from increased risk for diabetes, heart attacks and premature death (Ann Intern Med, 2017;166(4):257-267). That study was financed by International Life Sciences Institute, an industry trade group largely supported by agribusiness, food and pharmaceutical companies and whose members have included McDonald's, Coca-Cola, PepsiCo and Cargill, one of the largest beef processors in North America. The ILSI "has long been accused by the World Health Organization and others of trying to undermine public health recommendations to advance the interests of its corporate members" (New York Times, October 4, 2019). Johnston said he was not required to disclose this conflict of interest because he received the money more than three years ago.
Flaws in These Papers
• The authors of these articles concluded that warnings linking meat consumption to heart disease and cancer are not backed by strong scientific evidence, yet they cited mostly observational studies, which cannot possibly show cause and effect. This type of study is never accepted to determine whether or not a prospective new drug is safe.
• The authors failed to include the countless studies that have shown that meat shortens lives and causes various diseases in animals.
• The authors did not include studies that compared vegetarians and meat eaters, and did not report on what non-meat-eaters ate in place of meat. If you replace meat with sugar and other refined carbohydrates, you are not likely to benefit at all and you may increase risk for heart attacks and cancers because a high rise in blood sugar appears to increase heart attack and cancer risk even more than eating meat. Walter Willet, the former chairman of nutrition at Harvard, said that meat should be replaced with healthful, plant-based protein sources.
• Bonnie Liebman, Director of Nutrition at the Center for Science in the Public Interest, says, "One of the study's chief flaws is its reliance on the Women's Health Initiative study, a huge analysis of 48,000 women that had half the participants eating their regular diet and half eating a low-fat diet, which led to a half-ounce difference in meat consumption per day in the two groups, about a fifth of a hamburger. There was little difference in outcomes between the two groups, and because of its size, the Women's study may have skewed the overall results of the Annals of Internal Medicine report."
• Dr. Neal Barnard, founding president of the Physicians Committee for Responsible Medicine, said that none of the reported studies compared the health of those who eat meat against those who don't eat meat. He said that we do not know how much meat is safe to eat, if any; the Seventh Day Adventist studies show that people who eat no meat at all are the healthiest. It is irresponsible to tell people that they can eat meat without setting some limit. "We don't tell people to cut down on cigarettes. We tell them to stop smoking."
• The one review of randomized papers on the safety of meat included many studies that were funded by the meat industry.
• The authors of these studies exonerating meat did not include the Lyon Heart trial or the PREDIMED trial, which both showed that eating meat was harmful.
• Restricting meat has been shown to have as strong a health benefit as eating lots of fruits and vegetables, exercising, or not smoking. Frank Hu of Harvard states that, "A moderate reduction in meat could reduce mortality by 7.6 percent, or about 200,000 deaths per year."
• The evidence is so strong that processed meat is associated with increased cancer risk that the World Health Organization calls it a carcinogen (Annals of Oncology, Aug 2017;28(8):1788-1802).
• There is almost no debate in the scientific community that cooking meat without water (frying, broiling and so forth) forms polycyclic aromatic hydrocarbons (PAHs) that are proven carcinogens (Cancer Med, 2015 Jun; 4(6): 936-952).
• Meta analyses of epidemiological studies indicate that the long-term consumption of red meat and particularly of processed meat is associated with an increased risk of death, heart disease, colorectal cancer and type 2 diabetes in both men and women. The association persists after correcting for confounding factors, such as age, race, weight, smoking, blood pressure, blood fats, exercise, and other dietary factors (Int J Vitam Nutr Res, 85(1-2), 2015, 70-78).
See my recent reports on Red Meat, Neu5Gc and Risk for Cancer
Heart Attacks Again Linked to Red Meat
Fried and Browned Foods Linked to Shorter Lives
Even Occasional Meat May Be Harmful