At a time when vegetarians and environmentalists are urging consumers to reduce the animal protein they buy and consume, others say that protein, including animal protein, is nutrient-dense and has positive health benefits.
Donald K. Layman, professor emeritus, Department of Food Science and Human Nutrition at the University of Illinois at Urbana-Champaign, cites a national nutrition policy that works as "fear of fat" which encourages removing fat from the diet. "We're losing muscle mass and protein mass. We have too little protein," he said in a phone interview in March. Earlier he was a speaker at the Ohio Beef Council-sponsored program for dietitians in Columbus. Protein is needed for bone structure and diseases of bones are age-related. The basic structure of bone is a matrix of protein with deposits of minerals.
A diet with a moderate amount of protein improves weight management and heart health. Two recently published research studies - the March edition of the Journal of Nutrition and the January edition of Nutrition & Metabolism - concluded that overweight/obese adults can lose weight and decrease their risk factors for metabolic syndrome and type 2 diabetes by following a moderate carbohydrate, moderate protein diet. Those on the moderate protein diet reduced their body fat and improved blood lipid levels (decreased triglycerides and increased HDL, the beneficial cholesterol).
He defines a moderate protein diet as 100 to 130 grams of protein per day. The average adult woman has 65 to 75 grams protein per day, he said.
Consuming high-quality protein can help people increase a feeling of fullness and energy and maintain lean tissue, which leads to improved weight management and heart health, according to Shalene McNeill, executive director of nutrition research for National Cattlemen's Beef Association.
Mr. Layman says that saturated fat in fried food, candy bars, fats, and pastries rather than in meats, are the culprit in raising LDLs (the bad cholesterol). "The biggest impact on blood lipids is your weight," he said.
As people figure out the best diet for weight loss, many believe that saturated fat and cholesterol are the only issues. "We've tried that for 35 years. The longer we use that philosophy, the fatter we get," he said, noting that processed carbohydrates cause people to overeat. "We consume too many desserts and candy bars."
There also is increasing discussion of sarcopenia, the loss of lean muscle mass with age. Dietary protein can stimulate muscle protein synthesis and reduce muscle loss as individuals age. The optimal amount of protein that should be consumed to protect baby boomers from sarcopenic muscle loss is about four ounces (or 25 to 30 grams high-quality protein, or 10 grams essential amino acids per meal). High-quality protein can be found in beef, pork, eggs, fish, poultry, and dairy products.
It has been reported that adolescent and older females do not consume enough protein and very few are consuming the recommendations of the USDA's food guide MyPyramid.
According to Ronald Zernicke, the University of Michigan's director of Bone & Joint Injury Prevention & Rehabilitation Center, protein is essential for developing and maintaining healthy skeletal tissue. Carbonated beverages and sugar-filled sports drinks can decrease bone mineral density. Protein is extremely important for proper bone growth, especially in young athletes and physically active growing children. Athletes should be consuming at least 1,200 to 1,500 mg of calcium a day by way of low-fat, low-sodium dairy products, vegetables, greens, or supplements.