Having a balanced protein intake across all meals can help prevent age-related muscle loss.
As we age, we lose muscle mass and muscle function, known as sarcopenia. Sarcopenia makes older adults more susceptible to frailty, mortality, and falls. Thus, maintaining healthy muscle mass is important to prevent these adverse effects of aging.
Typically, muscle mass is increased by consuming protein-rich foods, like meat or dairy. The Recommended Dietary Allowance (RDA) for protein consumption is the same across age and gender groups. However, the dietary recommendations do not stipulate how often, or how much protein per meal should be ingested. Recent studies show that older adults should eat more protein per meal to maximize the formation of muscle mass.
Lack of evidence surrounding protein intake habits among young, middle-aged, and older adults led researchers at the University of Birmingham to study protein consumption patterns across these age groups. The study is published in Frontiers in Exercise and Sport Nutrition.
The researchers recruited 120 participants for the trial and divided the participants into three separate groups based on age: young, middle, and old. Forty young participants with an average age of 23, forty middle-aged participants with an average age of 51, and forty older adults with an average age of 77 were included in the study.
The participants were required to complete a three-day food diary that detailed the time, method of preparation, weight, and brand of food and drinks consumed. The researchers asked the participants to complete the diary over two weekdays and one weekend-day.
After the diary was complete and returned to the researchers, the amount of protein per meal was calculated. Protein sources included the following: red meat, poultry, eggs, bread, cheese, milk, protein supplements, fish, nuts, yogurt, soya, oats, muesli, and vegetarian meat substitutes.
The researchers found that most of the participants met the RDA for protein consumption. However, there was not a balanced protein intake across all meals. Rather, all groups ate protein unevenly throughout the day. Protein sources were similar across age groups, except at lunch, where older adults consumed more plant proteins, which are lower quality proteins.
Even though the majority of participants met the RDA, the study indicates that the RDA does not take into account the fact that older adults require more proteins to maintain muscle mass. The RDA does not have guidelines for this population, highlighting the need for updated nutritional guidelines. The researchers recommend a balanced protein intake for older adults by increasing protein consumption at breakfast and lunch.
Future studies should assess exercise frequency in addition to protein intake. Physical activity is another way to form muscle mass. Studying the interaction between protein consumption and regular exercise can help form guidelines to prevent muscle loss in older adults.
Written by Shayna Goldenberg
1. A more balanced protein intake can reduce age-related muscle loss. EurekAlert!. https://www.eurekalert.org/pub_releases/2020-03/uob-amb031620.php. Published 2020. Accessed March 18, 2020.
2. Smeuninx B, Greig C, Breen L. Amount, Source and Pattern of Dietary Protein Intake Across the Adult Lifespan: A Cross-Sectional Study. Front Nutr. 2020;7. doi:10.3389/fnut.2020.00025
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