Studies have repeatedly linked red meat with increased risk of heart disease, apparently because it is often loaded with artery-clogging saturated fat. But chicken – and even fish if fried – can contain at least as much saturated-fat as lean cuts of beef, pork or lamb. Studies have also linked red meat with cancer and diabetes. But those risks – if they are confirmed by further research – may stem more from processing and cooking methods and heavy consumption than from any inherent dangers of the meat. Here is a rundown of the known and possible risks.
Read Meat and Your Heart
Saturated fat clearly raises blood levels of the “bad” LDL cholesterol. Expert guidelines recommend no more than 20 to 25 grams of saturated fat per day for most people. But an 85-gram serving of roasted rack of lamb packs 11 grams of that fat; pork spareribs, nearly 10 grams; and regular ground beef, 6 grams. And most people eat much more than those modest amounts: Restaurants, for example, may serve 200-to 250-gm meat portions; that much rack of lamb could supply roughly double the daily recommended limit for saturated fat in one serving.
But numerous studies have shown that beef’s effects on LDL cholesterol are no worse than chicken’s if the red meat is sufficiently lean. And some cuts are surprisingly low in saturated fat. For example, an 85-gram serving of roast beef or fat-trimmed top sirloin has less than 2 grams of saturated fat. Dark-meat chicken with skin supplies roughly twice that amount; duck with skin quadruple that amount. Skinless dark chicken has about as much saturated fat as those red meats and more total fat and calories. And vegetarians are not doing their heart any favours by choosing cheese and paneer made from full-fat milk over meat which, gram for gram, may pack more saturated fat than that present in red meat.
Red Meat, Cancer and Diabetes
Two huge observational studies involving nearly 500,000 Europeans and 150,000 Americans, published in 2005 suggest that red meat may increase the risk of colorectal cancer. The studies found that those who ate meat at least 8 to 11 times per week upped their cancer risk by over 40 per cent than those who ate the least. People who consumed processed meats – bacon, sausage, and cured lunch meats – at least three times a week were 50 per cent more susceptible to colon cancer. In contrast, both studies found reduced risk among frequent fish eaters, and one of the two found the same for chicken lovers.
In trying to explain those findings, researchers have largely exonerated saturated fat as a colon-cancer culprit. But they have two other main suspects:
Heterocyclic amines. Grilling, broiling, or frying creates high temperatures that transform substances in meat into cancer-causing chemicals, notably heterocyclic amines (HCAs). Charring increases that transformation. Further, grilled meat can become coated with HCAs from smoke, created mainly by fat dripping onto hot coals. In a 1997 retrospective study by the US-based National Cancer Institute of about 175 stomach-cancer patients and 500 healthy people, those who preferred beef medium-well or well-done had more than three times the cancer risk compared with those who liked it rare or medium-rare.
But grilling, broiling, or frying fish and chicken also create HCAs; whether the types and amounts are more or less dangerous than those from beef is not clear. The cancer institute says the risk posed by HCAs for humans is uncertain, and it has set no guidelines on acceptable levels in food.
Heme iron. This combination of iron plus a protein called heme, each concentrated in red meat but not poultry and fish can trigger the formation of carcinogenic compounds known as nitrosamines in the large intestine. In addition, processed meats such as cured lunch meat, bacon, and sausage contain nitrate and nitrite preservatives that the gut converts to nitrosamines. Those compounds may help cause not only gastrointestinal cancer but possibly also pancreatic damage that can lead to diabetes. A 2004 study of nearly 70,000 women found that the risk of diabetes was 36 per cent higher in those who are the most red meat and 60 per cent higher in the biggest processed-meat eaters.
However, the researchers also suggest that the meat eaters’ apparently increased risks of cancer and diabetes may have actually stemmed from other reasons, such as inadequate exercise and scanty intake of plant-based foods, not from meat itself. Especially since other studies have failed to connect red meat with those diseases. Overall experts say the evidence suggests but by no means proves that meat contributes to cancer and diabetes.
Hormones, antibiotics, and infections. Antibiotics and various hormones or hormone like substances are given to cattle, hogs, and sheep to promote growth. Any hormone although there’s currently no evidence of direct harm to human health, the European Union has banned hormone use in livestock, in part because of concerns about a possible cancer risk. And the hormone residues may pollute the waterways.
Chicken and fish harbour chemicals, too. Poultry, like cattle, hogs, and sheep, are given growth-promoting antibiotics; that practice fosters drug resistance. And chickens are fed arsenic to kill parasites. Some tests abroad have found enough arsenic in a few chicken livers to cause neurologic problems if eaten regularly. And some fish are high in mercury and other potentially harmful contaminants. In addition, while mad cow disease risk is still exceedingly small, the risk of getting bacterial infections, such as food poisoning, is many times higher from poultry than from red meat.
