Current recommendations in the US are for 56 grams per day of protein for men, and 46 grams per day for women for all age groups (about 0.8 g protein/kg body weight/day).
“However, evidence continues to build in favor of increasing this recommendation for optimal protein intake to 1.0 to 1.2 g/kg body weight/day for adults older than 65 years,” wrote the authors in Clinical Nutrition.
“Taken together, evidence shows that when usual dietary protein intake does not meet increased protein needs of older adults, negative nitrogen balance results and protein levels decline, especially skeletal muscle proteins.”
Muscle loss is a natural part of aging, and researchers have estimated that, after the age of 50, we lose 1-2% of our muscles each year. Strength declines as well, at a rate of 1.5% per year beginning at 50 years and accelerating to 3% after the age of 60.
According to a monograph from the US Dairy Export Council, the direct health care cost attributable to sarcopenia were estimated to be $18.5 billion in 2000 in the US, a number that represented about 1.5% of health care expenditures for that year.
‘White water rafting without a paddle’
In our feature on sarcopenia last year, Jose Antonio, PhD, CEO of the International Society of Sports Nutrition (ISSN), told us that just adhering to the recommendations for protein is not enough. “It is about time that clinicians realized that consuming protein ABOVE the Recommended Dietary Allowance is needed to ameliorate the loss of muscle protein with age,” he said. “Adhering to the RDA for protein would be like white water rafting without a paddle. It's just plain dumb."
The calls for a change are getting louder – the new position paper, written following a workshop on protein requirements in the elderly by the European Society for Clinical Nutrition and Metabolism (ESPEN), calls for healthy older people to be consume at least 1.0 to 1.2 g protein/kg body weight/day, with higher amounts needed for at risk populations, including malnourished older adults or those at risk of malnutrition because they have acute or chronic illness. Protein intake should be in combination with daily physical activity or exercise, added the expert group.
Echoing other position papers
Phanin Leksrisompong, PhD, director of business development for Davisco Foods International told us that, in addition to this expert group, the PROT-AGE Study group published an “important position paper” recently that also recommended the average daily intake at least in the range of 1.0 – 1.2 g protein/kg body weight/day for healthy adults.
The PROT-AGE recommendations for dietary protein intake in healthy older adults also noted that the per-meal anabolic threshold of dietary protein/amino acid intake is higher in older individuals should be 25 to 30 g protein per meal, containing about 2.5 to 2.8 g leucine, in comparison with young adults, she added.
Preventing deficiencies, not optimal health
“The industry as a whole and scientific organizations need to be involved and work together to ensure this message get across to the key policy makers,” added Dr Leksrisompong. “Policy makers need to be convinced that nitrogen balance is not an adequate criterion for adult health (probably okay for growth) and the something like cardiometabolic outcomes would be more appropriate for adult health.
“In addition to influencing policy makers, it is important for us to educate the public/consumers,” she added. “The number of aging population across the globe is higher than ever and this number continues to increase.
“The current protein requirements are set at a minimum need which was established to prevent deficiencies (0.8 g/kg body weight/day) and not for health optimization. New research about the importance of skeletal muscle in treatment or prevention of obesity, type 2 diabetes, metabolic syndrome, heart disease, and sarcopenia have led to a re-thinking about the role of dietary protein in adult health.
“The current one-size-fits-all protein recommendation does not consider age-related chronic diseases, changes in metabolism, and frailty etc. In addition to increasing the amount of protein, the dietary guideline needs to emphasize the right amounts of protein at each meal, instead of amount of protein per day.”
What is the purpose of recommendations?
Donald Layman, PhD, from the University of Illinois, author of a recent editorial in the journal Nutrition and Metabolism that called for dietary guidelines to reflect new understanding about adult protein needs and for people to eat more than the RDA, questioned the purpose of the RDI (of RDA).
“Is the purpose to define a minimum or an optimum for health?” he told us. “By definition from the Institute of Medicine (IOM), the DRI state the RDA is the minimum to prevent inadequacies. Do we need to redefine the minimum or simply use the DRI range of intake (0.8 to 3.0 g) to develop optimum health diets?
“The RDA for Carbs is 130 g/day and Americans eat 300g/day. Why do we limit protein to the RDA and recommend Carbs at 2 to 3 times the RDA?”
Source: Clinical Nutrition
Published online ahead of print, doi: 10.1016/j.clnu.2014.04.007
“Protein intake and exercise for optimal muscle function with aging: Recommendations from the ESPEN Expert Group”
Authors: N.E.P. Deutz, J.M. Bauer, R. Barazzoni, et al.