Mitch Nisley, Ph.D. student studying monogastric nutrition, and Dr. Nicholas Gabler, Professor in Swine Nutrition at Iowa State University, summarized this 2016 peer-reviewed research article by Dr. Jung Eun Kim and colleagues. This review of nutritional studies discusses how eating higher amounts of protein while dieting can benefit overall health for older adults.
Major Finding
Adults over the age of 50 (classified as “older adults”) were studied under different diets while in a calorie deficit. One group consumed high levels of protein with more than 25% of their daily total energy intake coming from dietary protein each day (or ≥ 1.0 g/kg body weight/day). The other group consumed normal levels of dietary protein with less than 25% of daily total energy intake coming from protein each day (or < 1.0 g/kg body weight/day).
The older adults who consumed high levels of protein kept more lean tissue and lost more fat mass in comparison to those who consumed normal levels.
Why It Matters
Obesity and sarcopenia (age-related muscle loss) are among the most common and harmful conditions in older adults, and both significantly contribute to higher mortality and morbidity rates in this demographic.
Physicians often recommend weight loss to older adults to enhance overall health, longevity, and quality of life. This study highlights effective methods to achieve these goals.
Increasing protein intake during dieting helps reduce fat while preserving muscle mass, addressing both obesity and sarcopenia. Combining this dietary approach that increases lean protein intake with exercise can significantly boost the health and well-being of older adult men and women.
How the Research Was Conducted
Jung Eun Kim and colleagues conducted a meta-analysis using data from published randomized controlled trials involving subjects over 50 years old. In each trial included in the analysis, subjects were in energy (caloric) restriction and varied in both their sources of protein consumed (animal and plant) and the way meals were provided and monitored.
All studies included measured body composition (total lean tissue and fat mass) using dual-energy X-ray absorptiometry (DXA). Participants were placed into two groups based on their total daily protein intake or proportional daily protein intake to assess the effects of protein intake on body composition. Data were then analyzed to understand how dietary protein intake can impact changes in body composition among dieting older adults.
Learn More
Read the full peer-reviewed journal article to learn more about consuming protein and its effect on health in older adults.