A new study has revealed that a diet rich in protein and low in calories can help older adults with obesity lose more weight while maintaining muscle mass and improving bone density.
Older adults often lose bone density and muscle mass when they concentrate on shedding weight.
This unwanted bone and muscle loss can result in mobility issues and can even increase a person's risk of injury.
A recent study, which Wake Forest University in Winston-Salem, NC, is the lead on, has shown that a high-protein, low-calorie diet can help adults avoid these problems.
Several peer-reviewed journals, which include Journals of Gerontology: Medical Sciences and American Journal of Clinical Nutrition have accepted four research papers from the study for publication.
The researchers randomly selected 96 adults over 65 years of age and assigned them to one of two groups.
They put the first group on a 6-month, low-calorie meal plan that was also high in protein — more than 1 gram (g) of protein per kilogram (kg) of body weight. They assigned the other group to a weight-maintenance plan that included 0.8 g of protein per kg of body weight.
Those in the high-protein, low-calorie diet group experienced the most weight loss, but more revealing was that those in this group maintained their muscle mass. They also lost weight on the stomach, hips, thighs, and rear, which can decrease the risk of certain medical conditions, including diabetes and stroke.
Furthermore, the researchers found that the participants in the high-protein group improved their bone quality, and they gained 0.75 points on their Health Aging Index scores, involving longevity and mortality biomarkers.
Kristen Beavers, assistant professor of health and exercise science at Wake Forest and lead investigator of this study, led earlier, smaller studies where she scrutinized the planning and preparation of the participants' meals. For this study, though, with its greater number of participants, she wanted to find a more cost-effective method.
Consequently, the study asked those in the weight-loss group to use four meal replacements every day and to prepare two meals of lean protein and vegetables each day. The team allowed each participant one healthy snack per day to wrap up a low-calorie, high-protein meal plan. Those in the other group were instructed to maintain their regular diet and usual activities.
Older adults and nutrition
Older adults have unique nutritional needs and may need to make changes to their diets as the years go by. Muscle mass can decrease as a natural part of aging, and people do not burn calories at the same rate as they do during their younger years.
Targeting nutrient-dense foods is essential for older adults, and avoidance of high-calorie foods that lack vital nutrients is crucial.
Beneficial foods include fruits, vegetables, whole grains, lean meats, seafood, poultry, eggs, legumes, and low-fat dairy. Portion control may also be necessary — for older adults especially — as people may eat more food than they need.
It can be challenging to cook for a smaller family, so experts sometimes suggest cooking ahead and freezing portions to eat later when cooking is less appealing.
The particulars of this latest study seem to mirror the nutritional needs of older adults. However, the authors suggest that the addition of more protein may be the key to avoiding some of the unhealthful pitfalls that can take place when an older adult loses weight.
"This study suggests that a diet high in protein and low in calories can give seniors the health benefits of weight loss while keeping the muscle and bone they need for better quality of life as they age."
Lead investigator Kristen Beavers