Nutrition plays a vital role in the immune system’s ability to fight off, and recover from, infection. Steven Pearson-Brown explains how nutritional screening can identify and minimise the risk of long Covid, and shares some of the screening tools OH practioners might use.
The immune system provides vital protection against the world around us. This complex system not only seeks to find and destroy pathogens, but it also facilitates the repair and replacements of parts of the body which become damaged due to the infection and subsequent immune response.
Over the past two years, much attention has been given to determining the role of nutrition in the protection and recovery from Covid-19. So, what have we learnt so far?
Evidence shows that good nutrition not only supports immunity against disease, but is also an essential factor for the promotion of recovery (Farrara, et al. 2020). Not surprisingly, a vital component of the immune system is nutrition, specifically proteins and the amino acids from which they are made. In a recent interview with the BBC (2021), a professor of nutritional immunology within medicine from the University of Southampton, Prof Philip Calder, explained that “during infection, proteins are drawn from the muscle and broken down into amino acids, which the immune system uses to make new proteins”.
Many people find that they lose weight and experience muscle weakness during illness because of increased requirements for protein and energy. This increase continues post-infection to support the recovery stage. However, it can be impeded by several factors, such as poor appetite, fatigue, presence of anosmia and ageusia, co-morbidities and socioeconomic factors such as finances, access to food, living situations and support, (Berry, 2021). Therefore, some individuals, such as older adults and those with chronic conditions, are at increased risk of developing malnutrition (Farrara, et al. 2020), which can be both a cause and consequence of immune dysfunction (Gem COVID, 2020).
Throughout the pandemic, it has been observed that some cohorts of the population have been affected disproportionally, particularly those with chronic diseases that are adipose-based, dysglycaemia-based and cardiometabolic-based (Burridge, 2020). These have also been found to have required more intervention to facilitate recovery (Zabetakis, et al. 2020).
Nutritional screening and assessments are important to identify people at risk as soon as possible, facilitating early intervention (Donnelly, et al. 2021). However, it is essential that these assessments are thorough, with appropriate follow-up actions available. Poor screening in those who are already compromised may result in worse clinical outcomes (Farrara, et al. 2020).
Who to screen?
It is recommended that those with co-morbidities and those with more severe disease should have a nutritional screening and assessment (Malnutritional pathway, 2022). Given the variety of symptoms, particularly those that can impact nutritional intake (see the table below), and in those individuals with post Covid-19 syndrome (sometimes called long-Covid, defined as experiencing symptoms of Covid-19 12 weeks post-infection), then an argument for screening all those affected could be made, as outlined in the national guidance for post-COVID syndrome assessment clinics (2020).
A validated malnutrition screening tool such as the Malnutrition Universal Screening Tool (MUST) or the Mini-Nutrition Assessment short Form (MNA-SF), is recommended to determine an individual’s risk (Malnutritional pathway, 2022). However, it is beneficial to gather further information which goes beyond the simplified tools.
Using a more general nutritional assessment, such as the patient association nutrition checklist (2018) can help identify any current or potential difficulties or barriers to improving nutritional intake, such as access to food, swallowing difficulties, and so on. This can be useful for individuals who are overweight or obese, and/or who have a history of sub-optimal eating patterns, as this may have resulted in nutritional deficiencies/insufficiencies, which have not been identified, but which could diminish immune function.
According to the rapid guideline for managing the long-term effects of Covid-19, 67% of UK GPs have patients with post-Covid syndrome. Although the lungs are the primary target for virus, as shown by the common symptoms, other organs such as the heart, kidney or digestive tract can be affected via other mechanisms involved in the immune response (GEM COVID, 2020).
Mechanick, et al. (2021) noted that nutritional screening can be important in those with post-Covid syndrome to prevent further deterioration in health, highlighting that in these individuals the inflammatory process can exacerbate catabolism and anorexia, aggravating malnutrition further and impeding recovery, potentially resulting in disability and reduced quality of life.
How can occupational health help?
Occupational health (OH) has an important role in supporting the wider healthcare system, through the regular health monitoring of employees (NHS). OH is uniquely placed to develop and act on opportunities to provide screening to identify nutritional challenges in those affected by post Covid-19 syndrome. By utilising validated tools, individuals can be provided with the appropriate level of support or, where appropriate, referred for further specialist support, such as input from a dietitian.
BAPEN (2022). MUST Calculator. [Online] Available at: https://www.bapen.org.uk/screening-and-must/must-calculator
Berry. S., (2021). Nutrition and COVID-19 Recovery: Diet and COVID. [Online} Available at: https://www.youtube.com/watch?v=4-a-h1MfJu0
BBC (2021). How your diet can improve COVID-19 recovery. Article by Sue Quinn. [Online] Available at: https://www.bbc.co.uk/food/articles/diet_for_covid19_recovery
Burridge J, Bradfield J, Jaffee A, Broadley I, Ray S. Metabolic health and COVID-19: a call for greater medical nutrition education. Lancet Diabetes Endocrinol. 2020 Aug;8(8):665–6. [Online]. Available at: https://www.thelancet.com/pdfs/journals/landia/PIIS2213-8587(20)30220-5.pdf
Donnelly R, Keller H. Challenges Providing Nutrition Care During the COVID-19 Pandemic: Canadian Dietitian Perspectives. J Nutr Health Aging [Internet]. 2021 Jan 9 [cited 2021 Mar 4]; Available from: http://link.springer.com/10.1007/s12603-020-1585-z
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Mechanick JI, Carbone S, Dickerson RN, Hernandez BJD, Hurt RT, Irving SY, et al. Clinical Nutrition Research and the COVID-19 Pandemic: A Scoping Review of the ASPEN COVID-19 Task Force on Nutrition Research. JPEN J Parenter Enteral Nutr. 2021 Jan;45(1):13–31. [Online]. Available at: https://doi.org/10.1002/jpen.2036
National guidance for post-COVID syndrome assessment clinics (6 November 2020) [Internet]. Patient Safety Learning – the hub. [cited 2021 Jan 9]. Available from: https://www.pslhub.org/learn/coronavirus-covid19/guidance/national-guidance-for-post-covid-syndrome-assessment-clinics-6-november-2020-r3465/
Nestle Nutrition Institute. Mini-nutrition assessment short form – MNA-SF. [Online]. Available at: https://www.mna-elderly.com/sites/default/files/2021-10/mna-guide-english-sf.pdf
Occupational Health. NHS employers. [online] Available at: https://www.nhsemployers.org/articles/occupational-health
The Patient Association (2018). Nutrition checklist. [Online] Available at: https://www.patients-association.org.uk/Handlers/Download.ashx?IDMF=3449fca0-dc52-4f06-ac75-3050b71d7bb5
University of Plymouth (2021). Dietetics COVID-19 Knowledge hub: Managing symptoms linked to nutrition during COVID-19 recovery: Symptom toolkit. [online] Available at: https://www.plymouth.ac.uk/research/dietetics-and-health/covid-knowledge-hub/professionals/symptoms
University of Plymouth (2021). Dietetics COVID-19 Knowledge hub: Assessing patient’s nutritional needs and setting realistic goals during COVID-19 recovery. [online] Available at: https://www.plymouth.ac.uk/research/dietetics-and-health/covid-knowledge-hub/professionals/assessment
Zabetakis I, Lordan R, Norton C, Tsoupras A. COVID-19: The Inflammation Link and the Role of Nutrition in Potential Mitigation. Nutrients. 2020 May 19;12(5):1466. [online] Available at: https://doi.org/10.3390/nu12051466