Ageing alters the impact of nutrition on immune function

Abstract

Immunosenescence during ageing is a major challenge which weakens the ability of older individuals to respond to infection or vaccination. There has been much interest in dietary strategies to improve immunity in older people, but there is an assumption that modulation of the immune response in older people will be based on the same principles as for younger adults. Recent evidence suggests that ageing fundamentally alters the impact of nutrition on immune function. As a result, interpretation of data from studies investigating the impact of diet on immune function is highly dependent on subject age. Study design is critically important when investigating the efficacy of dietary components, and most studies involving older people include rigorous inclusion/exclusion criteria based on medical history, laboratory tests, general health status and often nutritional status. However, immunological status is rarely accounted for, but can vary significantly, even amongst healthy older people. There are several clear examples of age-related changes in immune cell composition, phenotype and/or function, which can directly alter the outcome of an intervention. This review uses two case studies to illustrate how the effects of n-3 PUFA and probiotics differ markedly in young v. older subjects. Evidence from both suggests that baseline differences in immunosenescence influence the outcome of an intervention, highlighting the need for detailed immunological characterisation of subjects prior to interventions. Finally, future work elucidating alterations in metabolic regulation within cells of the immune system as a result of ageing may be important in understanding the impact of diet on immune function in older people.

Malnutrition in the elderly

“…28 This immune-related biological ageing is referred to as immunosenescence, which contributes to a progressive deterioration of immune function and vaccine-response and increased risk of cancer and chronic and autoimmune diseases. 28,29 Vitamin and mineral deficiencies, such as vitamin E and zinc, as a result of malnutrition, can further add to this issue by causing an overall decline in immune function, including an impaired T-cell response, decreased lymphocyte proliferation and reduced delayed-hypersensitivity response. 7,26,28 In addition to maintaining optimal micronutrient levels, the use of n-3 PUFAs and probiotics has also been researched for their potentially positive impact on the elderly immune system.…”

A Review on the Serum Electrolytes and Trace Elements Role in the Pathophysiology of COVID-19

“…The nutritional condition should control in COVID-19 patients, and its disorders must be managed especially in patients associated with poor outcomes, including elderly, impaired wound healing, higher rates of nosocomial infections, and all-cause mortality. When malnutrition occurred, the immune response also is weakened [3]. Patients with insufficient nutrition status should receive nutrition as soon as possible.…”

Food science and COVID-19

“…The efficacy of micronutrients and other dietary interventions in infections can be affected by numerous factors, such as the type of pathogen, the dose and duration of administration and the age, genetics, lifestyle, immunological and nutritional status of the study participants [ 32 ]. In particular, immunosenescence during aging changes the impact of nutrition on immune function [ 33 ]. Furthermore, prolonged supplementation of food bioactives and micronutrients at high doses may have adverse effects and may even aggravate infectious diseases [ [34] , [35] , [36] ].…”