Protein and Other Ways to Naturally Support Immunity

How does the Immune System Work?

The immune system is a complex one. It relies on multiple players (organs, proteins, cells) to act in a synchronized manner in order to defend the body against harmful substances otherwise known as antigens.  There are two main types of immunity known as innate and adaptive immunity. You are born with innate immunity whereas adaptive immunity is acquired from contact with antigens. When the body encounters an antigen such as the coronavirus or flu virus, an initial wave of antibodies is produced to “mark” the invasive substance and then a second, different wave of antibodies is sent to destroy the now-marked antigens. These specialized antibodies remain in the body and this is how adaptive immunity is acquired to things bodies have been infected with.

The immune system also appears to be interconnected to factors such as health status, diet, physical activity level, age, psychological stress and more, though the exact relational mechanisms are not clear at this time.

Can you Boost your Immune System?

Technically, there is no way to actually “boost” your immune system. The immune system can function optimally or sub optimally, but it cannot be made to function supra optimally.

Given the worldwide spread of COVID-19, consumers have increasingly purchased foods and supplements targeting immune health as well as other ways to support a healthy immune response.  While a properly-functioning immune system cannot prevent any type of infection including coronavirus, it can help to mitigate the severity of infection and reduce the recovery time of infection. Proper hygiene is the only way to currently prevent any type of bacterial or viral infection.

What Nutrients or Foods Support the Immune System?

There are specific nutrients which the body needs to support a properly functioning immune system. Some of the main ones include:


Amino acids found in dietary protein are the building blocks of antibodies, which in turn help to fight off invasive pathogens. As such, adequate protein intake is essential to a healthy immune response. Without enough protein each day, the body can fall short on protective antibodies and thus impair the immune response. Low protein intake can also lead to greater severity of infection as well as a reduced ability to recover from an infection.

Additionally, there are three specific amino acids that play a direct role in the immune response:

  • Glutamine is a conditionally essential amino acid which supports the proliferation of lymphocytes (a type of antibody) and the production of cell-signaling cytokines
  • Arginine is a conditionally essential amino acid which supports the proliferation and optimal function of T cells (a type of white blood cell)
  • Cystine is an essential amino acid which is needed for T cell activation and proliferation


A growing body of evidence shows that there is a relationship between gut bacteria and the immune system. Generally, when the gut is healthy, the immune system functions optimally. And studies have indicated that a healthy colony of gut bacteria helps to decrease the susceptibility of infection from harmful pathogens.

Probiotics are helpful, living bacteria commonly found in yogurt and other fermented foods like tempeh, kimchi and kefir. They can also be found in supplements. There are hundreds of different strains of probiotics. When consumed, probiotics help to balance the amount of good and bad bacteria in our gut and intestinal tract, plus they also help to replenish good bacteria after it’s been lost (such as after taking a course of antibiotics).


Zinc is an essential mineral that plays a key role in immune function. Specifically, zinc helps to develop and activate T-lymphocytes, a type of antibody that directly attacks viruses, bacteria and other antigens.  In fact, research shows that a zinc deficiency leads to increased susceptibility to infections.

Zinc is found in a variety of foods, added to foods, or may also be found in supplements or over-the-counter cold remedies. Some naturally rich sources of zinc include:

  • Animal-based:
    • Oysters
    • Beef
    • Crab
    • Lobster
    • Pork
    • Chicken
  • Plant-based:
    • Baked beans
    • Pumpkin seeds
    • Fortified breakfast cereal
    • Cashews

Zinc is more bioavailable from animal-sources than from plant sources because many of the plant-based sources (such as beans and grains) naturally contain phytates which bind to zinc and may limit its absorption. This is why many vegans and vegetarians require as much as 50% more zinc than non-vegetarians. The recommended dietary allowance (RDA) for an adult male is 11mg per day and for an adult female is 9mg per day.


Vitamin C is an essential vitamin which also plays a central role in the immune response. Specifically, vitamin C helps to direct neutrophils (a type of white blood cell) to the site of infection and defends them against damaging free radicals. It also helps skin act as a barrier against pathogens.

Vitamin C is found in various fruits and vegetables or in supplements. Some of the richest sources include red peppers, orange juice, grapefruit, kiwis, broccoli and strawberries. The daily RDA for adult males is 90mg per day and 75mg per day for adult women.

Vitamin A, D and E also support a healthy functioning immune system.

  • Vitamin A can be found in sweet potato, spinach, carrots, sweet red peppers cantaloupe and more.
    • The RDA for vitamin A for an adult male is 900 mcg RAE and 700 mcg RAE for adult females
  • Vitamin D can be obtained through exposure to direct sunlight, fortified milk or orange juice, UV-treated mushrooms, cod liver oil and a few more.
    • The RDA for Vitamin D is 600 IU or 15mcg per day for both men and women
  • Vitamin E is found in many seeds and nuts such as sunflower seeds, almonds, sunflower oil, hazelnuts, peanut butter and more.
    • The RDA for vitamin E is 15mg per day for both males and females above the age of 14

What are Non-Food Ways to Support the Immune System?

Sleep Enough Each Day

Sleep appears to specifically benefit T-cells, the antibodies that help to destroy targeted antigens. Without enough sleep, the immune response may be impaired.

Exercise Regularly

Exercise also contributes to a healthy immune system by helping the body find and deal with harmful substances, and reduces the risk of infection by slowing down the changes to the immune system that occur with aging.

And while it was previously believed that too much exercise weakened the immune system, a recent meta-analysis found that infections were more likely to be linked to inadequate diet, insufficient sleep, psychological stress and exposure to pathogens at gatherings rather than too much exercise.

Manage Stress Levels

Chronic stress can weaken your immune system and make the body more susceptible to illness. It does this by creating consistent inflammation that harms body tissues and suppressing immune cells needed to fight infection.

While some stress is inevitable, it’s important to find ways to manage stress such as meditation, exercising or aromatherapy.

Don’t Smoke

There are over 7,000 chemical compounds found in cigarette smoke which can damage all types of cells in the body including those that are part of the immune system. Smoking reduces the body’s ability to fight infection and impairs the immune response.