Zinc and Selenium: The Ultimate Immune Boosting Combo

You’ve probably always been told to drink your orange juice when you’re not feeling well, but as it turns out, OJ may not be the secret to keeping your immune system in check.

While vitamin C no doubt plays a critical role in immunity, there are two far-less well-known nutrients that pack a power punch where immune function is concerned.

Zinc and selenium are two trace minerals that may not be required in large amounts, but play a significant role in supporting your natural immune defenses.

And while widely available in food, deficiency of these guys runs rampant, which means getting your levels up to par is critical if you want to avoid lugging around a Kleenex box with you or being bedridden for weeks at a time because you caught the flu.

We’re covering two of the biggest and most powerful immune-boosting nutrients out there—zinc and selenium—and how combining them may just supercharge your immune system

Zinc And Selenium 101

We all know that proper nutrition is key to keeping the body healthy and functioning at its peak. The immune system is no different, but when we dive into what it takes to keep the immune system working at its prime, we can see that there are a few key nutrients that play a major role in protecting the body from illness and infection. Of those nutrients, zinc and selenium is a power duo.

As trace minerals, both of these nutrients are required in relatively small amounts, and the RDI can generally be fulfilled through diet. However, chronic diseases or poor absorption can heavily interfere with the amounts of these nutrients, making supplementation a good alternative to avoid adverse effects.

A study of patients admitted to a hospital’s infectious disease ward showed that zinc and selenium were among the most prevalent micronutrient deficiencies in these people, finding that two-thirds of the patients were deficient in zinc, and almost half were also deficient in selenium ¹.

And with millions of people worldwide also being deficient in these key nutrients, it’s no wonder we have a population with comprised immunity.

Zinc And Immunity

Zinc plays one of the most important roles in supporting immune function through direct, indirect, and antioxidant pathways ^2-5. Zinc is involved in more than 300 enzymatic reasons and is an essential trace mineral required for proper growth, development, and maintenance of immune function.

However, its influence extends beyond just the immune system to virtually all organs and cell types, representing a major part of roughly 10% of the human proteome, and encompassing hundreds of key enzymes and transcription factors ³.

The importance of zinc in immune function is best represented in zinc-deficient populations, where low levels have been associated with skin abnormalities, hypogonadism, cognitive impairment, growth retardation, and imbalanced immune reactions favoring allergies and autoimmune diseases ³.

Zinc homeostasis is essential for several aspects of the immune system, including hematopoiesis, cell maturation and cell differentiation, cell cycle progression, and proper function of various immune cells ⁴.

Deficiency of zinc has been suggested to be linked to elevated inflammatory mediators, (ROS, antimicrobial peptides), which causes subsequent tissue injury, especially in the liver, lungs, and spleen ³.

Receive unique insights, advice and exclusive offers.

Email address Subscribe

As well, specific cellular functions like the intracellular killing of pathogens, cytokine production, along with ROS production all depend on adequate levels of zinc, and a zinc deficiency adversely affects the maturation and function of T and B cells.

It also interferes with neutrophil functions, including phagocytosis, oxidative burst, degranulation, cytokine production, chemotaxis, and neutrophil extracellular trap (NET) formation ^{5, 6}.

And if that’s not enough, zinc deficiency also causes weakened NK cell function, impaired cytokine function and secretion, and impaired development and function of the entire immune system, including both the innate and adaptive branches.

Selenium In Immune Function

Selenium, on the other hand, appears to play just as big of a role in immune function as zinc does due to its incorporation into selenium-containing proteins called selenoproteins.

Among the enzymes most impacted by a selenium deficiency are glutathione peroxides; they are a family of selenoproteins that exhibit powerful antiviral and antioxidant properties.

Of the four major GSH peroxidases, GPX1 is hit the hardest. Its primary function is to reduce oxidative stress by utilizing glutathione to reduce hydrogen peroxide to water, thereby decreasing the damaging effects of this radical on immune cells ⁷.

In a state of selenium deficiency, it’s been shown that GPX1 levels can drop by as much as 10%, which impairs immune response against viruses and allows them to replicate freely.

Studies also suggest that not only does a selenium deficiency contribute to an increased risk of infection, but it also contributes to the emergence of new and more virulent flu strains ⁸.

Children with the H1N1 subtype of influenza were found to have low blood levels of selenium, along with a 45% reduction in GPX1 activity and a staggering 245% increase in CRP levels, suggesting that virus-induced oxidative stress may play an important role in the pathology of the H1N1 virus ⁹.

The main reason why selenium is linked to a strong immune response is partly because selenoproteins are essential for activating T-cell function, and because T cells are heavily influenced by oxidative stress, selenoprotein-deficient T cells cannot proliferate in response to T-cell-receptor stimulation, which means that production of reactive-oxygen species increases ¹⁰.

With that said, the many biological effects of selenium are attributed to its role in selenoproteins, which are involved in the activation, proliferation, and differentiation of cells that drive both innate and adaptive immune responses.

As such, adequate serum concentrations of selenium are not only important for initiating and enhancing immune function, but also for immunoregulation, which is key for preventing excessive immune responses that can contribute to the development of chronic disease.

Who Is At Risk Of A Zinc And Selenium Deficiency?

Both zinc and selenium are widely available in food sources, but due to processing and manufacturing practices, on top of environmental health decline, levels of these minerals in food isn’t what it was once.

And when you’re consuming a plant-heavy diet, other factors play into how your body absorbs zinc and selenium.

For meat-eaters, zinc is heavily concentrated in all sorts of animal meat products, but for those who follow a plant-based diet, zinc is present in much lower concentrations, and what is there is generally inhibited by the presence of anti-nutrients that interfere with its absorption, meaning vegans and vegetarians are at a higher risk for deficiency.

Other factors that influence zinc levels include:

• Age
• Weight
• Concurrent diseases (IBD, autoimmunity, kidney or liver disease)
• Medication use
• Malabsorption disorders

Selenium is also widely present in food sources but concentrations are heavily influenced by environmental conditions. Due to mineral soil depletion, many foods that naturally contain selenium are lower in the mineral than they were 50 years ago ¹¹.