Importance of Nutritional Status on Immune Health

A major cause of mortality in the US is acute respiratory tract infections. Viruses cause seasonal outbreaks and, as we are seeing now, a global pandemic that is impacting public health and the economy. Most of the attention has been focused on social distancing, wearing masks, and proper sanitation which are all important; however, public health discussions have not been focused around nutritional strategies to support optimal immune health. This is essential as more serious outcomes are associated with those with coexisting health concerns, smoking, and the elderly population.

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Researchers demonstrated the importance of nutrition and its role in the immune system in a review published two weeks ago in Nutrients. The findings indicate that numerous studies have demonstrated the role of nutrition in supporting the immune system, as nutrient deficiencies can alter cytokine production, decrease the number of lymphocytes, impair wound healing, and decrease antibody responses.

Specific minerals, vitamins, and omega-3 fatty acids support the immune system, and a deficiency can increase the risk of infections. Vitamins and minerals help support a normal inflammatory response, support and maintain physical barriers, produce antimicrobial proteins, and assist in the production of cytokines and antibodies. Vitamins C and D specifically are crucial for immune health. Vitamin C supports immune cells, antibody production, and is also a powerful antioxidant. One meta-analysis showed a decrease in the duration and severity of upper respiratory tract infections, a significant reduction in the risk of pneumonia, and a significant decrease in the risk of infection with vitamin C supplementation at doses greater than 200 mg per day.

Vitamin D is also critically important for immune health. Previous research has shown that vitamin D supplementation reduced the risk of influenza. Vitamin D deficiency has also been associated with an increased risk of acute respiratory distress syndrome as well as chronic disease. I recommend a daily dose of at least 2000 IU per day; but, many individuals may need 5,000 - 10,000 IU per day to obtain optimal levels. It is also necessary to take a vitamin D with another fat soluble vitamin, like K, for absorption.

Zinc has also been shown to play a role in the immune system. A deficiency leads to impaired formation, activation and maturation of lymphocytes, and a weakening of the innate host defense.

In addition, dietary intake of omega-3 fatty acids has shown to be essential for supporting the immune system, as they contain anti-inflammatory processes.  In animal studies, specific types of Omega-3's, EPA and DHA, are shown to have a protective effect against lung injury and acute respiratory distress syndrome. A recent study showed a significant improvement in blood oxygenation, reduction in ventilation requirements, organ failure, length of stay, and mortality. An intake of 250 mg of EPA and DHA is recommended, but many patients may need closer to 1500 - 3000 mg to optimize their levels of omega-3s.

These studies demonstrate that proper nutrition, including supplementation, is a safe and effective way to support a healthy immune system. It is difficult for most people to obtain an optimal intake of all these nutrients in the diet. Therefore, supplementation should be considered. Additional nutrients to consider include vitamin A, resveratrol, quercetin, and melatonin. All of the mentioned supplements are available in office, and D3 Ultra with K and Omega Max are available online.

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Source: Calder P, Carr A, et al. Optimal Nutritional Status for a Well-Functioning Immune System Is an Important Factor to Protect Against Viral Infections. Nutrients. 2020 Apr 23;12(4), 1181