The paper states between 15 to 30% of older people globally are affected by malnutrition (or 60% in care homes) and suggests specialised nutrition solutions could help mitigate nutrient deficiencies and boost immune systems where a ‘food first approach’ is not possible.
The body’s immune defences naturally degrade with age (a phenomenon known as immunosenescence), however common nutrient deficiencies among the elderly exacerbate the issue and increase the risk of disease and infection.
DSM Senior Scientific Affairs Manager Global Medical Nutrition & Pharmaceutics, Barbara Troesch explains: “Anorexia of ageing is a complex and multifactorial condition associated with loss of appetite and/or decreased food intake. It can be the result of alterations in digestive function, hormonal fluctuations, disease, pain and changes in smell, taste, and vision, which strongly influence appetite.”
Furthermore, compromised immunity as a result of malnutrition in the over 70’s, leads to poorer responses to vaccinations, which is demonstrated in the higher frequency, spread and severity of many infections in long-term care facilities.
Troesch comments: “The same mechanisms that generate an effective immune response to infection also help to generate immunity to vaccination. It is therefore believed that micronutrient deficiency contributes to poor vaccine response.”
Seniors are susceptible to malnutrition due to physiological changes that lower appetites and affect their ability to absorb essential nutrients. Age-related medications may also interfere with the metabolism of certain micronutrients, the paper says.
A balanced diet (and nutritional intake) promotes healthy immune systems and protects the body from pathogenic organisms, including bacteria and viruses, shielding the body from disease and infections. However ageing affects both innate (fast and non-specific) and adaptive (slow, antigen-specific) immunity, leaving individuals particularly vulnerable to illness.
Immunity decreases due to an irreversible reduction in cell development, mitochondrial dysfunction, and oxidative stress.This supresses the barrier function of the skin, mucus, and gut lining, and weakens the immune system’s ability to prevent pathogens entering the body – and when it does respond to pathogens it is less efficient.
The body’s innate inflammatory response is also less productive and provokes an “exaggerated inflammatory response” that impedes the ability to reduce inflammation – a process referred to as ‘inflammaging’. This contributes to accelerated aging and age-related diseases associated with underlying chronic inflammation, including cardiovascular disease, cancer, sarcopenia, and Alzheimer’s.
Troesch emphasises the importance of nutritional balance to maintain fully functional immune cells and ensure effective responses to pathogens. Supplementation with vitamins and minerals would boost the body’s immunity and attenuate some of the physiological changes associated with malnutrition.
“Because of anorexia of ageing, older individuals are less likely to obtain the nutrients and energy they need to maintain optimal immune function,” she says.
Vitamin C plays an important role to maintain innate and adaptive immune responses and relieve excessive inflammation in acute respiratory infections like pneumonia, for example. Meanwhile, vitamin D offsets the negative effects of inflammation by promoting antimicrobial peptide synthesis to reduce pathogens, and vitamin A and zinc help regulate cell division, and stimulate production of immune cells.
“It’s important to support older individuals with nutrients and minerals linked to strong immune health, like vitamin C and D, as well as zinc, copper, iron and selenium.”
Troesch adds that a ‘food first’ approach is recommended but if this is not possible (and an older person is at high-risk of malnutrition) specialised nutrition products, like oral nutritional supplements, could help reduce malnutrition and create a solid foundation for a healthy immune response.