no comments

Immune system boosting foods to include in your diet

Close up of young person shopping for fresh organic fruits in farmer's market with a cotton mesh eco bag.

Feed your immune system with these foods

We hear so much about the immune system, but what is it and how does it work? Are there immune system boosting foods? Can changes in your diet and lifestyle improve your immune system? Let’s talk about protecting your body from disease by eating foods that boost the immune system.

What is the immune system?

The immune system is the body’s first line of defense against harmful viruses, disease, and sickness. There are two components of the immune system: the innate immunity and the adaptive (acquired) immunity.

The innate immune system detects viruses, bacteria, toxins, parasites, etc., and recognizes wounds or trauma to the body [1]. The adaptive immune system develops over time as your body is exposed to microbes (a bacterium, virus, germ, bug, etc.) or chemicals released by microbes [1].

These two components work together to keep you healthy. With the help of the innate immune system, which patrols the body, the adaptive immune system can change to defend itself as needed.

Immune systems are very complex. For immune systems to function best, many factors need to be in balance, such as sleep, physical activity, nutrition, stress, and environment.

Why food is important to your immune system

While many factors play a role in your overall health, nutrition is a huge component. Consuming a nutrient-poor diet has been linked to chronic health conditions, such as diabetes, high blood pressure, heart disease, cancer, and obesity. If you have one of these conditions, any external microbes or toxins could threaten a busy immune system.

Consuming a few healthy foods in your diet or taking supplements when you’re sick is not enough to boost your immune system.

Immune system boosting foods and nutrients

A balanced diet containing a variety of vitamins and minerals will support your body’s ability to fight infection and disease.


Proper hydration is crucial for healthy, functioning bodies. Water is vital for the kidneys and other bodily functions. From lubricating joints to making minerals and nutrients available in the body, water is important for an optimally functioning immune system. If you’re looking for additional ways to stay hydrated, fruits and vegetables contain a lot of water.

Whole foods and plant-based foods

Eating organic foods is filling and reduces consumption of processed foods that negatively impact your immune system. Whole, plant-based foods also contain different types of fiber; fiber intake of Americans is about half of what it should be. A diet rich in fruits and vegetables provides the fiber that builds a healthy gut microbiome [2].

A healthy gut has a lot to do with the body’s immune system. Researchers at Johns Hopkins have been studying how diseases change the gut’s composition and how these changes affect the immune system. One researcher stated that a huge portion of the immune system is in the GI tract. Although your immune system is inside your body and some bacteria are outside, they still interact. Therefore, feeding your gut healthy food helps your immune system function optimally [3].

Probiotic-rich foods

Fermented foods, such as yogurt, kimchi, sauerkraut, and kefir, contain probiotics that can help build a healthy digestive system. Eating probiotic-rich foods can help with gut health and your immune system.

Healthy fats

Aim to consume naturally occurring fats from whole foods, such as avocados, nuts, seeds, fatty fish, and olive oil. Avoid foods with partially hydrogenated oils in the ingredient labels.

Foods to avoid for your immune system

To keep your body at its healthiest to fight viruses, especially during flu season, it’s best to avoid or limit the consumption of the following foods:

Ultra-processed foods/Common food preservatives and additives

Recent studies [4] have assessed the potentially harmful effects of some chemical food additives on the immune system.

These foods are considered ultra-processed (potato chips, cookies, packaged goods, frozen dinners, etc.) and lack essential nutrients to support healthy immune function, including vitamin D, vitamin C, zinc, magnesium, calcium, potassium, B vitamins, etc.

MSG (Mono-sodium Glutamate), a flavor-enhancing food additive found in soups and sauces, can cause chronic inflammation in some people and affect liver health. Aspartame, a non-nutritive sweetener found in more than 4,000 products worldwide, may cause an inflammatory response in some people [5].


Consuming excessive salt and small amounts of potassium can contribute to high blood pressure. High blood pressure can then contribute to heart disease and/or stroke. Salt can be found in high quantities in many processed foods (soups, processed meats, cheese, frozen meals, fast food, etc.).


Added sugars found in juice, soda, syrups, sweetened cereals, flavored yogurts, and candy provide little to no nutritional value for your immune system [5]. Sugar can be tricky to spot on a food label as it goes by many names. Check ingredient labels for words ending in “ose,” e.g., fructose or sucrose.


When you consume excess alcohol, your liver works harder. This can weaken its functionality over time, which can disrupt interactions with other organs and cause inflammation. When maximizing your immune system functions, it’s best to eliminate or consume alcohol in moderation [5].

Omega-6 fatty acids

Avoid excess consumption of omega-6 fatty acids (found in oils such as corn, sunflower, grapeseed, peanut, vegetable, mayonnaise, many salad dressings, etc.). An imbalance of omega-6 and omega-3 fatty acids can cause the body to produce pro-inflammatory chemicals [5].

Good nutrition helps the whole body

By feeding your body a variety of whole foods, while reducing or eliminating those chemicals and substances that increase chronic inflammation, you can improve how your immune system functions.

This is only one lifestyle area that impacts our immune systems, so it is best to consider how you can improve not only your diet, but also your sleep, exercise, environment, and stress management. If you need help, consider connecting with a care manager.


1. COVID-19: The Inflammation Link and the Role of Nutrition in Potential Mitigation (

2. 2015-2020 Dietary Guidelines for Americans ( 

3. The Gut: Where Bacteria and Immune System Meet (

4. IJERPH | Free Full-Text | Investigating Molecular Mechanisms of Immunotoxicity and the Utility of ToxCast for Immunotoxicity Screening of Chemicals Added to Food (