How does healthy nutrition support optimal immune and vaccine responses? Leading experts explain

• Against the backdrop of the global COVID-19 pandemic and vaccine rollout, ensuring optimal immune and vaccination responses is key to protecting populations worldwide. Sufficient nutrient status has been shown to support immunity and reduce the risk and impact of infections, by supporting immune cells that destroy harmful pathogens and produce antibodies – the same cells that help to generate an effective vaccine response.^1,2
• A recent review has highlighted the relationship between nutrient and omega-3 status and immune function, and explored their potential impact on COVID-19 infection.³ In this blog, we get an expert perspective on the paper from lead author Mette M. Berger, Professor of Intensive Care at Lausanne University Hospital, and co-author Manfred Eggersdorfer, Professor in the Department of Healthy Ageing at University Medical Center Groningen.
• Read on to discover how adequate nutrition supports immune health and vaccination responses, the potential global implications of the new review and its call to action, and why micronutrient supplementation could play a role in better assuring optimal immune health and robust vaccine responses across population groups.

Find out more about how nutrition lays the foundation for optimal immune and vaccine responses – click here to watch dsm-firmenich's on-demand webinar featuring renowned nutritional immunology expert, Prof. Philip Calder.

Why is there increased focus on micronutrients, immunity, and vaccinations?

The COVID-19 pandemic has brought into sharp focus strategies to keep the spread and impact of infection under control. At the same time, we are seeing an unprecedented vaccination rollout across the globe. As a result, there is now more interest than ever in how supporting optimal immune health and robust vaccination responses could complement measures put into place to manage the pandemic – and there is a growing body of evidence that suggests micronutrient status could play an important role.

How do micronutrients support immune health and vaccine response?

Based on an extensive body of preclinical and clinical data, it is widely accepted that the immune response is supported by an adequate status of nutrients such as vitamins A, B6, B12, C, D, E, and folate, as well as omega-3 polyunsaturated acids (PUFA), zinc, selenium, copper and iron.¹

Vitamins and minerals have been shown to support a number of immune cells in their unique functions: macrophages, which destroy pathogens; T cells, which kill cells infected with viruses; and B cells, which secrete protective antibodies.1 These same cells also play a role in generating the body’s response to vaccinations.⁴

Given that these micronutrients and fatty acids play important roles in the immune response, it is not surprising that a growing body of evidence supports their role for reducing the risk and impact of COVID-19. For example, many associational studies and meta-analyses have reported that inadequate vitamin D status increases the risk for infection and for increased severity of outcomes.^5,6 In addition, a recent publication reports that supplementation of omega-3 fatty acids or multivitamins is also associated with a decreased incidence of COVID-19, particularly in women (Louca et al., 2021). The potential importance of these micronutrients in relation to COVID-19 is described further below.

These nutrients are also important to support responses to vaccines. For example, a meta-analysis of nine influenza vaccination studies revealed that those deficient in vitamin D were 1/3 less likely than those with adequate status to generate ‘seroprotective’ levels of antibodies to two of the three strains in an influenza vaccine.⁷ This is especially important, as those who are ‘seroprotected’ typically are expected to have a 50% reduced chance of becoming ill with the flu.⁸ In another study, supplementing healthy elder adults with 200 mg/day of vitamin E for four months was shown to significantly improve response to the hepatitis B vaccine – a T cell dependent vaccine that is often impaired in older adults.⁹ Due to data such as these, a growing number of experts recommends supplementing with micronutrients to support immune and vaccine responses.^10,11,12

What has the new review found?

Titled ‘Strengthening the immunity of the Swiss population with micronutrients: a narrative review and call for action’, the paper examines the links between certain nutrients, immune function, and COVID-19 infection.³

Prof. Berger explained: “To date, COVID-19 has infected over 600,000 people and is responsible for over 9,000 deaths in Switzerland.13 In comparison to other European countries with similar socio-economic and healthcare status, infection and mortality dynamics and numbers have remained high – especially when compared to the Nordics.¹⁴ With Nordic countries’ focus on inhabitants’ nutritional status having potentially contributed to lower incidence and improved outcomes,¹⁵ our review aimed to explore the potential for nutritional guidance as a strategy to support immunity and health outcomes particularly in groups at risk of insufficient intakes during the pandemic.” 

A key part of the review was summarizing the influence of nutrients on the immune system, pointing to specific nutritional risks in the Swiss population relating to immunity. “It is well-documented that micronutrient deficiencies or suboptimal status can negatively influence immune function and reduce resistance to infection. While population representative data for Switzerland is limited, existing data suggest that dietary intake is low for vitamin C, vitamin D, iron, selenium, zinc and omega-3 PUFAs,” said Prof. Eggersdorfer. “This is particularly concerning, as the elderly population – who are a major at-risk group for COVID-19 – has been shown to have an increased risk of inadequate nutrient intake.”^12,16

While the review solely focused on the Swiss population, its findings could hold relevance in other regions. Eggersdorfer commented: “Interestingly, despite the review taking place in a developed country where access to healthy nutrition appears to be abundant, we observed a significant risk of nutrient deficiencies and low adherence to national dietary recommendations. And this situation is likely the case elsewhere.”

Why supplementation could help

Indeed, while adequate nutrient status to support immune function can be achieved through a balanced, diversified diet, insufficient intakes and nutritional inadequacies are very common. This is not only seen in the recent review of the Swiss population, but also reflected in figures from other countries worldwide, such as the US - where 45% of adults in a study of over 26,000 Americans were found to have inadequate dietary intakes of vitamin A, 46% for vitamin C, 95% for vitamin D, 84% for vitamin E and 15% for zinc.¹⁷ These figures support the reality that the nutrient levels required to support an optimal immune response (including mechanisms related to antibody generation) cannot easily be achieved through everyday diet alone.¹¹ It is here that dietary supplementation could be one way to support strategies to tackle COVID-19, along with social distancing, hygiene measures, vaccination etc.

“Supplementation with modest doses of a combination of specific micronutrients may be a safe, efficient and effective way to fill the nutrient gap and support immune health in populations worldwide. While the available studies on nutrient administration after someone is diagnosed with COVID-19 do no show improvement of outcome,18 there are indications that optimal nutritional status before exposure, may reduce disease incidence and severity,”^5,10,19 said Prof. Berger. “Targeting vulnerable groups with supplementation of moderate doses of immunity-supporting nutrients – such as vitamins C and D, as well as selenium, zinc – and omega-3 PUFAs could complement other established methods to reduce the impact and severity of COVID-19. Given the role of nutritional status in supporting immune function, encouraging optimal nutrient intake through supplementation could provide the foundation for an optimal vaccine response – particularly in older adults.”¹¹

Transforming scientific insights into immune health innovation

With immune health a key concern for 60% of consumers and 43% specifically worried about resistance to epidemic diseases,²⁰ this growing bank of scientific evidence offers an opportunity for dietary supplement manufacturers to address consumer health concerns and needs. dsm-firmenich’s broad portfolio of high-quality products, customized solutions, and expert services support manufacturers in transforming the latest science into new innovations in the dietary supplement space to respond to global conversations around immune health and vaccines. 

Contact dsm-firmenich to learn how our end-to-end capabilities, scientific services and market-ready solutions can help you bring research-backed immune health solutions to consumers quickly, safely and effectively.