Research suggests including protein as part of a calorie-restricted diet is effective for weight loss and improved physical function
Including nutrient-rich lean pork as part of a weight-loss diet could help women achieve their weight-loss success and improve their ability to get around, according to new research published in Current Developments in Nutrition.1 Duke University researchers found high-risk, obese women following weight-loss diets, which included lean pork, experienced significant weight loss, improved physical function and were able to stick to the approach during a six-month period – all important factors for the health and well-being of older women.
Researchers tested the impact of two different calorie-restricted diets in 80 obese women, ages 45 and older. Diets included adequate protein as determined by the Recommended Daily Allowance, or a higher level of protein – including 30 grams of high-quality protein per meal, with lean pork as the major protein source. Both groups lost approximately six percent of their body weight over the six-month period.
“The health benefits of weight loss for those who are obese are clear, but we all know weight loss is not easy,” said lead study author Connie Bales, Ph.D., Professor of Medicine at Duke University. “While more research is needed to understand the specific benefits of protein in a weight-loss diet, this research suggests a calorie-restricted diet including lean, nutrient-rich pork, could be a very viable option for reducing obesity and improving future health and function.”
Diet Impacts Physical Abilities
Preserving functional abilities is crucial to help maintain independence and the capability to perform day-to-day tasks, especially in older adults. Also being obese puts older adults at higher risk for functional decline. One concerning risk of weight loss in older adults is they’ll unintentionally lose lean body mass (muscle) along with the fat. In this study, both groups lost small amounts of muscle; however, participants experienced significant improvements in functional capacity at six months.
Participants on “higher” protein diets experienced significant improvements in key physical function measures such as walking farther and functional movement at four months, and both groups experienced improvements in these measures at six months. These findings appear to agree with another recent study by the same researchers showing clear protein benefits to physical function in a similar study of 67 high-risk, obese adults following a lower-calorie diet with 30 grams of high-quality protein at each meal.2
Racial Disparities in Weight Loss
The researchers also found surprising differences in weight loss among many of the study participants. While not originally expecting to see racial differences, they found African American women lost less weight than Caucasian study participants and tended to have lesser functional improvements–findings that concerned the study researchers.
“We also found Caucasian women were more likely to fully complete study participation compared to the African American women,” said Dr. Bales. “These novel differences underscore the need for more research to find culturally-specific approaches for weight loss,” said Dr. Bales.
Including Lean Pork in a Weight-Loss Plan
The dieters incorporated Smithfield lean pork products – tenderloin, low sodium ham, chops and lean ground pork – into two of three daily meals. They also shared recipes and their favorite ways to incorporate these cuts into meal planning. An important part of any weight-loss plan is its feasibility, and a key aspect to success includes taste.
In this study, lean pork was an easy and enjoyable way to incorporate more protein into the higher-protein diet. “The women in this study enjoyed eating pork to meet their protein goals,” said Dr. Bales. “Including foods people enjoy could go a long way in helping them stick to their weight-loss plan.”
Nutrient-Rich Pork: Part of an Overall Healthy Eating Pattern
While more research is needed, this study adds to a growing body of evidence that shows eating lean, high-quality protein, like pork, can help people lose or maintain weight by contributing to people feeling full and by preserving lean muscle. 3, 4, 5, 6 ,7
“Lean pork is a great way to incorporate protein as part of any healthy diet,” said Adria Huseth, registered dietitian and manager of nutrition communications and research at National Pork Board. “It’s nutrient-rich, as well as a versatile, affordable and accessible protein for most Americans. Its many beneficial qualities make it easy to incorporate into any healthy eating plan.”
- Source of Key Nutrients: Pork is a good source of protein and provides several important vitamins and minerals. A 3-ounce serving of pork is an “excellent” source of thiamin, selenium, protein, niacin, vitamin B6 and phosphorus, and a “good” source of riboflavin, zinc, and potassium.8
- Lean Protein: Today’s pork is 16 percent leaner and 27 percent lower in saturated fat compared to 20 years ago.9 Seven cuts of pork meet the USDA guidelines for “lean” by containing less than 10 grams of fat, 4.5 grams of saturated fat and 95 milligrams of cholesterol per 100 grams of meat.10 Pork tenderloin has the same amount of fat as a skinless chicken breast.
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