Scientists Say Red Meat Vital for a Healthy Diet
Harvard food guidelines ignore scientific dietary value of red meat.
Compiled by staff
Published: Jan 13, 2012
By Madeline McCurry-Schmidt
When Harvard University published its "Healthy Eating Plate" last September there was something missing: red meat.
Instead of including red meat on their dietary guide, Harvard nutritionists recommended consumers "choose fish, poultry, beans, and nuts." The exclusion of red meat from the Harvard guide contrasts with USDA's MyPlate, which counts lean cuts of beef, ham, and other red meats as good proteins sources for a healthy diet.
Some nutritionists say by excluding red meat from guidelines, Harvard scientists are ignoring significant benefits of red meat in the diet. Studies by groups like the British Nutrition Foundation show not only is red meat a good source of protein, it is also an important source of other nutrients.
In a paper published this month in the journal Meat Science, scientists from Baylor College of Medicine and the USDA-ARS Children's Nutrition Research Council explained red meat contributes important nutrients to the diet without harming dietary quality. Compared with a group on a diet without beef, consumers of high-lean, low-fat beef took in more vitamins A and C, B vitamins, niacin, phosphorus, magnesium, iron, zinc, potassium and protein.
Research also shows a diet containing lean red meat can actually improve heart function. In this month's issue of the American Journal of Clinical Nutrition, researchers from Pennsylvania State University, Oklahoma Medical Research Foundation, and Rutgers University published data showing that a diet with lean beef can decrease levels of LDL cholesterol, compared with diets of lean white meat. LDL cholesterol (commonly called "bad cholesterol") can transport fat molecules in the blood stream and contribute to cardiovascular disease.
Red meat is an especially important source of nutrients for infants. During the 2011 joint meeting of the American Society of Animal Science and the Argentine Association of Animal Production, British Nutrition Foundation senior nutritionist Laura Wyness gave a talk titled "Nutritional content and benefits of red meat."
Wyness said many infants in the UK show iron deficiency around six months old. She said this can happen when parents don't get their babies enough meat during weaning. During weaning, parents will replace milk with fruit and vegetable puree, and this limited diet leads to a lack of iron and zinc.
"It's important to start to wean onto meat," Wyness said.
Red meat is not just a good source of iron, but the type of iron in meat is more easily absorbed by the body than iron found in foods like spinach. A 1988 University of Washington study showed that the human body can absorb 15-35% of iron found in meat (called "heme iron") but only 2-20% of other types of iron. In their paper, titled "Iron nutrition and absorption: dietary factors which impact iron bioavailability," the researchers said adding meat to a diet could help individuals vulnerable to iron loss — such as pregnant women and menstruating women.
Wyness said red meat is also an important source of vitamin D. Though many people can get all the vitamin D they need from the sun, absorption is trickier for groups like the elderly and those with darker skin.
"That makes meat an important source," Wyness said.
Lean red meat, like the kind tested in the Meat Science study, is easy to find.
"Many popular cuts that you're familiar with are lean," said Shailene McNeill, executive director of nutrition research for the National Cattleman's Beef Association.
McNeill said consumers should look for beef products with "round" or "loin" in the name. Sirloin, tenderloin and flank steaks all fit the bill as lean red meats.
McNeill believes Harvard's guidelines on limiting red meat may come from a misperception that Americans eat too much meat already. She cited a Baylor University study which showed that Americans only eat, on average, 1.7 ounces of beef per day per person. For reference, 1.7 ounces is about weight of a medium-sized chicken egg.
"For calorie investment, that's making a huge nutrient contribution," said McNeill.
Adria Sheil-Brown, a dietician with the National Pork Board, added that proteins found in red meat can actually help people lose weight, a claim confirmed by years of nutrition research. In a 2004 paper titled "High-Protein, Low-Fat Diets Are Effective for Weight Loss and Favorably Alter Biomarkers in Healthy Adults," a team of Arizona State University scientists wrote that high-protein diets are also more satisfying. This means dieters are more likely to stick to high-protein diets and continue to lose weight.
Like McNeill, Sheil-Brown believes there are misconceptions about the value of red meat. She said many people don't realize that red meat can contain many nutrients but few calories. For example, a three ounce cut of pork tenderloin has under three grams of fats and around 120 calories.
"Pork tenderloin is just as lean as a skinless chicken breast," said Sheil-Brown. "The problem is just keeping your portion size in check – and that's true with any food."
McCurry-Schmidt writes for the American Society of Animal Science.
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