Optimising Protein Intake in Older Adults

As the life expectancy of people in the UK continues to increase, it is estimated that people aged 65 and over will make up almost a quarter of the population in the coming years¹. Remaining independent and healthy into later life is fundamental for quality of life in older adults and maintaining muscle mass and strength is essential for this². Sarcopenia is the decline in muscle mass that occurs as we age and can contribute to an increase in incidents of falls and fractures³, as well as increasing the length of hospital stays and overall mortality risk^4,5.

Why is protein important?

Protein is an important macronutrient for everyone, but research suggests that an increased protein intake is required to maintain nitrogen balance in the elderly in comparison with younger groups⁶. Age-related changes in the way the body responds to protein means that more is required to initiate muscle protein synthesis⁷. This is coupled with the fact that the rate of protein catabolism generally increases in older adults due to the higher incidences of acute and chronic inflammatory diseases⁸. It has been strongly suggested that by increasing protein consumption above recommended levels for the general adult population, this anabolic resistance can be somewhat counteracted⁹.

What are the recommendations?

In the UK, current guidelines recommend a Reference Nutrient Intake (RNI) of 0.75g of protein per kilogram of body weight per day¹⁰. This does not necessarily account for the increased needs that adults may have as they age.

The European Society for Clinical Nutrition and Metabolism (ESPEN) advises the following:

1. 1.2g of protein per kilogram of body weight per day for healthy older adults
2. 1.5g of protein per kilogram of body weight per day for older adults who are malnourished or at risk of malnutrition due to illness
3. Intakes above 1.5g of protein per kilogram of body weight per day in older adults who have a severe illness or injury¹¹.

What are current intakes like?

A 2020 study concluded that a significant proportion of older adults were not meeting current UK protein intake recommendations and even fewer were meeting the ESPEN healthy older adults recommendation7. These findings highlight that the older adult population isn’t consuming adequate protein to maintain muscle mass and slow the progression of sarcopenia. This is before additional factors which can impact on protein intake have been considered, such as acute and chronic illness and age-related changes in appetite.

How can protein intake be optimised?

• Include a source of protein at each meal to ensure a steady intake throughout the day:
  - Breakfast tends to be a carbohydrate rich meal so this is a great opportunity to introduce some protein e.g. swap a bowl of porridge for some scrambled eggs and toast.
• Increase overall protein intake by having protein-rich snacks throughout the day:
  - Cheese & crackers, yoghurts, and nuts are all great options
• Fortify meals and snacks if struggling with appetite
  - Add skimmed milk powder, milk, and cheese to things such as soups and sauces to boost protein intake without increasing the portion size.
• Consider oral nutritional supplements (ONS) if struggling to meet protein needs
  - ONS can be used to supplement the diet and there are wide variety available to suit individual needs.

What else can help?

Keeping active! Muscle protein synthesis is stimulated by exercise, and recent research highlights that consuming sufficient protein and participating in regular low intensity exercise may be a potential strategy for slowing the sarcopenic process¹². In addition, physical activity can help regulate appetite in older adults¹³ so including daily activity can work well on conjunction with advised dietary advice.

◄References:

1. Lewis, A. Housing an ageing population: a reading list. London: House of Commons Library; 2021 June. 15 p. Report no.: 09239.
2. Wolfe, R. The role of dietary protein in optimizing muscle mass, function and health outcomes in older individuals. British Journal of Nutrition. 2012;108(S2):S88-S93. Available from: https://pubmed.ncbi.nlm.nih.gov/23107552/
3. Reid, K and Reeves, S. Optimising protein intake in older people to maintain their musculoskeletal health. Nursing Standard. 2021;36(8):77-82. Available from: https://pubmed.ncbi.nlm.nih.gov/34308582/
4. Bayraktar, E et al. Relationship between Sarcopenia and Mortality in Elderly Inpatients. The Eurasian Journal of Medicine. 2020 [cited 16 May 2022];52(1):298-33. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7051235/#b18-eajm-52-1-29
5. Bianchi, L et al. The Predictive Value of the EWGSOP Definition of Sarcopenia: Results From the InCHIANTI Study. The Journals of Gerontology Series A: Biological Sciences and Medical Sciences. 2015;71(2):259-264. Available from: https://pubmed.ncbi.nlm.nih.gov/26333772/
6. Morais, J et al. Protein turnover and requirements in the healthy and frail elderly. The Journal of Nutrition, Health and Aging. 2006;10(4):272-83. Available from: https://pubmed.ncbi.nlm.nih.gov/16886097/#:~:text=We%20found%20that%20data%20from,feeding%20compared%20with%20young%20persons
7. Morris, S et al. Inadequacy of Protein Intake in Older UK Adults. Geriatrics. 2020;5(1):6. Available from: https://www.mdpi.com/2308-3417/5/1/6/htm
8. McClave, S et al. Guidelines for the Provision and Assessment of Nutrition Support Therapy in the Adult Critically Ill Patient. Journal of Parenteral and Enteral Nutrition. 2016;40(2):159-211. Available from: https://pubmed.ncbi.nlm.nih.gov/26773077/ (Aug 2021).
9. Dardevet, D et al. Important determinants to take into account to optimize protein nutrition in the elderly: solutions to a complex equation. Proceedings of the Nutrition Society. 2020;80(2):207-220. Available from: https://www.cambridge.org/core/journals/proceedings-of-the-nutrition-society/article/important-determinants-to-take-into-account-to-optimize-protein-nutrition-in-the-elderly-solutions-to-a-complex-equation/5690757C10C469AEEBC72DB8B0415524
10. Department of Health Panel on Dietary Reference Values. Dietary Reference values for food and energy for the UK; HMSO: London, UK, 1991; p. 24.
11. Deutz, N et al. Protein intake and exercise for optimal muscle function with aging: Recommendations from the ESPEN Expert Group. Clinical Nutrition. 2014;33(6):929-936. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4208946/
12. WALKER, D et al. Exercise, Amino Acids, and Aging in the Control of Human Muscle Protein Synthesis. Medicine & Science in Sports & Exercise. 2011;43(12):2249-2258. Available from: https://pubmed.ncbi.nlm.nih.gov/21606874/
13. Hubner, S et al. The Effects of Exercise on Appetite in Older Adults: A Systematic Review and Meta-Analysis. Frontiers in Nutrition. 2021;8. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8638160/#B25