Written by Jessica Patella, ND. Intake of less than 1 gram of protein per kilogram of body weight per day was negatively associated with muscle strength and performance later in life, especially in older women.
Sarcopenia is the loss of muscle mass, strength and functioning that occurs with age 1,2. This is of concern because a loss of muscle mass leads to fragility and increases the risk of injury, falls, broken bones and even death in the elder population 1,3. This has led to a debate on how much protein should be consumed in the older population. But until this point, little research had been conducted in the elderly, especially those above 85 years of age 1.
The current guidelines for protein intake is 0.8g/kg of body weight per day. However, the research to obtain this number was primarily in younger healthy adults. As people age, there is a decrease in muscle mass that occurs. Adequate protein intake has been identified as a major modifiable factor to help improve muscle mass in the older population 1,4. Recommendations have been suggested from 1.15 – 1.6g/kg of body weight in the older populations (65 years and above) but little research supported these numbers. For this reason, researchers set out for the first time to study people 85 years of age and older to determine if protein intake could affect muscle mass and strength 1.
The research was part of the Newcastle 85+ Study, which included 1,000 participants born in 1921 who lived in the Newcastle area of the U.K. For this study, 722 participants (289 males, 433 females) had protein intake measured (24-hour dietary recall) and were assessed for muscle functioning via grip strength and Timed Up-and-Go test (TUG) over a 5-year period (baseline, 18, 36 and 60 months) 1.
The results were as follows:
- At baseline, 390 participants (54%) (261 females) reported low protein intake (less than 1 g/kg body weight per day) which was associated with lower grip strength (1.62 kg less, p=0.008), which was even more so in the female population (-0.83 (0.41), p=0.05)).
- There was a decline in grip strength over 5 years but it was not associated with protein intake.
- Women with low protein intake was associated with a worse Get Up-and-Go (TUG) at baseline (p=0.03) compared to good protein intake, but this was not observed with men.
- There was a decline in TUG over 5 years but it was not associated with protein intake.
Intake of less than 1 gram of protein per kilogram of body weight per day was negatively associated with muscle strength and performance later in life, especially in older women. More research is needed to determine the optimal protein intake for adults later in life 1, as well as if protein supplementation may help with muscle strength and performance later in life.
Source: Granic, Antoneta, Nuno Mendonça, Avan Aihie Sayer, Tom R. Hill, Karen Davies, Ashley Adamson, Mario Siervo, John C. Mathers, and Carol Jagger. “Low protein intake, muscle strength and physical performance in the very old: The Newcastle 85+ Study.” Clinical Nutrition 37, no. 6 (2018): 2260-2270.
© 2017 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
Click here to read the full text study.
Posted July 20, 2021.
References:
- Granic A, Mendonça N, Sayer AA, et al. Low protein intake, muscle strength and physical performance in the very old: The Newcastle 85+ Study. Clinical nutrition (Edinburgh, Scotland). 2018;37(6 Pt A):2260-2270.
- Dodds RM, Roberts HC, Cooper C, Sayer AA. The Epidemiology of Sarcopenia. Journal of clinical densitometry : the official journal of the International Society for Clinical Densitometry. 2015;18(4):461-466.
- Cruz-Jentoft AJ, Landi F, Schneider SM, et al. Prevalence of and interventions for sarcopenia in ageing adults: a systematic review. Report of the International Sarcopenia Initiative (EWGSOP and IWGS). Age Ageing. 2014;43(6):748-759.
- Landi F, Calvani R, Tosato M, et al. Protein Intake and Muscle Health in Old Age: From Biological Plausibility to Clinical Evidence. Nutrients. 2016;8(5).
