Consuming protein throughout the day improves muscle strength in seniors

31 Aug 2017 --- Spreading the intake of protein equally among the three daily meals could be linked to greater mass and muscle strength in the elderly. Loss of muscle is an inevitable consequence of aging that can lead to frailty, falls or mobility problems, and eating enough protein is one way to remedy it. These are the findings of a study conducted at the Research Institute of the McGill University Health Centre (RI-MUHC) in collaboration with the Université de Sherbrooke and the Université de Montréal.

The results of the study, which were published recently in the American Journal of Clinical Nutrition, shed new light on the diets of people in an aging population. The research team examined both the amount of protein consumed and its distribution among people aged 67 and over, using the database from the Quebec longitudinal study on nutrition and aging called NuAge (Nutrition as a Determinant of Successful Aging).

“Many seniors, especially in North America, consume the majority of their daily protein intake at lunch and dinner. We wanted to see if people who added protein sources to breakfast, and therefore had balanced protein intake through the three meals, had greater muscle strength,” says the lead author of the study, Dr. Stéphanie Chevalier, who is a scientist with the Metabolic Disorders and Complications Program at the RI-MUHC and an assistant professor at the School of Human Nutrition at McGill University.

A rich database of nutrition data
The researchers analyzed data from the NuAge cohort, which included nearly 1,800 people who were followed for three years. They reviewed the protein consumption patterns of 827 healthy men and 914 healthy women aged 67 to 84 years, all residents of Quebec, trying to establish links with variables such as strength, muscle mass or mobility.

“We observed that participants of both sexes who consumed protein in a balanced way during the day had more muscle strength than those who consumed more during the evening meal and less at breakfast,” explains the first author of the study, Dr. Samaneh Farsijani, a former Ph.D. student at the RI-MUHC supervised by Dr. Chevalier.

All body tissues, including the muscles, are composed of proteins, which consist of amino acids. If the protein intake decreases, the synthesis is not done correctly and this leads to a loss of muscle mass.

“Our research is based on scientific evidence demonstrating that older people need to consume more protein per meal because they need a greater boost of amino acids for protein synthesis,” says Dr. Chevalier, adding that one of the essential amino acids known for protein renewal is leucine. “It would be interesting to look into protein sources and their amino acid composition in future studies to further our observations.”

Industry opportunity
In a recent interview with NutritionInsight, Dr. Ludger Eilers, Director of Evonik Health Care’s Food Ingredient Segment, notes that sarcopenia, or age-related muscle loss, offers a huge opportunity to the nutraceutical industry.

“After the age of 45, you lose 1 percent of your lean muscle mass per year,” Eilers points out. “If the industry can come up with an ingredient addressing sarcopenia, this would really have a bright future and would be spot on in the trend of healthy aging. This is something the industry should have a look at and innovate.”

“If you look at the consumer trends, the share of people over 60 years of age grows by roughly 3 percent per year and this is twice as much as the general population grows,” Eilers says of the rapidly changing demographics. “This is a growing market, and elderly people are particularly interested in products and nutraceuticals that work.”

“If you also look at the increasing health care costs, in the US the health care system spending per capita is more than US$9,000 per year, which amounts to almost 20 percent of the GDP per capita. It's clear that this is a tremendous opportunity for nutraceutical producers,” Eilers adds.

By Lucy Gunn