Including nutrient-rich lean pork as part of a weight-loss diet could help women achieve their weight loss goals and improve their ability to get around, according to new pork checkoff-funded research published in Current Developments in Nutrition.
Duke University researchers found that high-risk obese women following weight loss diets that included lean pork experienced significant weight loss and 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 either adequate protein, as determined by the recommended daily allowance, or a higher level of protein that included 30 g of high-quality protein per meal, with lean pork as the major protein source. Both groups lost approximately 6% of their bodyweight 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," lead study author and Duke professor of medicine Dr. Connie Bales said. "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 affects 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 risk tied to weight loss in older adults is that 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 the higher-protein diets experienced significant improvements at four months in key physical function measures, such as walking farther, and in functional movement, and both groups experienced improvements in these measures at six months. These findings appear to agree with a similar study by the same researchers showing clear benefits of protein for physical function in a recent study of 67 high-risk obese adults following a lower-calorie diet with 30 g of high-quality protein at each meal.
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 that African American women lost less weight than Caucasian 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," Bales said. "These novel differences underscore the need for more research to find culturally specific approaches for weight loss."
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.
This study used lean pork as an easy and satisfactory way to incorporate more protein into the higher-protein diet. "The women in this study enjoyed eating pork to meet their protein goals," Bales said. "Including foods people enjoy could go a long way in helping them stick to their weight loss plan."
While more research is needed, this study adds to a growing body of evidence that shows that eating lean, high-quality protein like in this study can help people lose or maintain weight by contributing to the feeling of fullness and by preserving lean muscle.
"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 the National Pork Board, which oversees the pork checkoff. "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."