Viruses can affect every body system, including the respiratory tract, gastrointestinal tract, skin, liver and brain. Cold and flu viruses are the most recognizable, with over 62 million cases of the common cold and an estimated 25 to 45 million cases of the flu plaguing the U.S. every year. But your body is equipped with a powerful ally, the immune system, to fight viruses off and prevent future infections from taking hold.
What you eat plays a big role in how well your immune system is able to wage war against invading viruses. Here’s what you can do to make sure yours is in top shape and ready for action.
A strong immune response relies on multiple body systems and cell types working together to identify and remove viruses and other pathogens.
What Is a Virus?
Viruses are pieces of DNA or RNA that use host cells to make copies of themselves. When a virus enters your body, it injects its genetic material into your cells. Infected cells make more viral genes, which either “bud” off cell surfaces or build up inside cells until they burst. Once new viral material is released, it goes on to infect other cells.
Innate and Adaptive Immunity
Invasion by a virus triggers your innate immune system. This generalized immune response helps your body get the infection under control but isn’t trained to target specific pathogens. That’s the job of adaptive immunity.
Adaptive immunity is mediated by T cells and B cells. T cells start out in the bone marrow and migrate to the thymus gland to mature. B cells originate and mature in bone marrow. While T cells “patrol” the body on the lookout for invaders, B cells create antibodies against known pathogens. This allows your body to recognize and fight back against viruses it’s encountered before.
Different types of T cells coordinate the adaptive immune response with help from lymph tissues throughout the body, including gut-associated lymphoid tissue (GALT) in the digestive tract. When immune cells identify viruses and other pathogens, they move in to destroy the invaders and return your body to a state of health.
Your immune system is best prepared to take action against viruses when you choose foods that provide a steady stream of key nutrients. Diets centered around whole plant foods in particular appear to stimulate natural killer cell activity. Natural killer cells are part of the innate immune response that hones in on pathogens, including viruses responsible for common respiratory infections.
Immune System Booster Foods
Some plant-based foods have properties that make them top choices for strengthening the immune system:
Other key nutrients for stronger immunity include vitamin C, magnesium and selenium. It’s important to get a wide range of nutrients from a variety of whole plant foods to ensure a strong immune response against viruses and other pathogens.
Foods That Weaken the Immune System
Some foods hinder immune function, which can make you more susceptible to viral infections:
These foods also have a negative effect on gut health, which can have serious consequences for all body systems. The combination of pro-inflammatory compounds and low fiber content skews the balance of bacteria in the gut, leading to a weakened gut wall and increasing the risk for chronic inflammation. Plant foods, by contrast, promote beneficial gut bacteria and are generally anti-inflammatory.
Shifting your eating patterns away from processed and animal foods toward more whole, plant-based options is one powerful step you can take to give your body the tools it needs to fight off viruses. For optimal immune function, make sure you’re also getting enough good-quality sleep, following a regular exercise regimen, keeping stress levels in check and practicing good hygiene. The more you can do to cultivate an overall healthy lifestyle, the stronger your immune system will be.
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