6 Foods for a Stronger Immune System

This time of year, it’s not uncommon for colds and viruses to start spreading. 

While there’s no magic food that will 100 percent protect you from getting sick, incorporating these six foods into your routine can give your immune system a healthy boost. 

1. Citrus Fruits: Essential Vitamin C for Immune System Support  

Let’s start with an obvious one first: citrus fruits. These brightly flavored and colored fruits are excellent sources of vitamin C. 

Vitamin C is a powerful antioxidant essential for a well-functioning immune system. 

Specifically, vitamin C promotes the production of white blood cells called lymphocytes. These cells are especially important for protecting the body against infection. 

Vitamin C also boosts the function of these white blood cells and plays a role in helping to maintain the skin’s protective barrier against potential infections. 

While studies haven’t shown that taking excess vitamin C can help prevent the common cold, it may help shorten the duration if you do get sick. 

The daily recommended intake of Vitamin C is 75 mg for women and 90 mg for men. To put that in perspective, one orange provides approximately 68 mg of Vitamin C, a high percentage of the daily value. 

2. Yogurt and Kefir: Probiotics for Immune Function and Gut Health 

Did you know that approximately 70 to 80 percent of your immune system is in your gut?

So, it shouldn’t be surprising that a healthy gut is vital for maintaining a strong immune system. 

In fact, some studies have found that probiotics can help prevent and treat various viral infections. 

So, how do you get probiotics?

Two excellent food sources include yogurt and kefir — just be sure to look for ones that say “live active cultures” on the label. 

Another advantage of these dairy products over probiotic supplements is that they’re often fortified with vitamin D.

Studies have shown that vitamin D helps initiate the immune response and can decrease our susceptibility to infection. 

3. Poultry as a Source of Vitamin B6 for Immune Support

Chicken noodle soup may already be your go-to when you’re sick, but did you know a moderate intake of chicken may help prevent you from getting sick in the first place? 

Chicken is a good source of vitamin B6 (also known as pyridoxine). One important function of vitamin B6 is stimulating the production of antibodies that are needed to fight off infection. Studies have shown that a deficiency in vitamin B6 can impair your normal immune functions. 

A 6-ounce serving of chicken provides approximately 1.6 mg of B6, which is the daily recommended value.

4. Nuts and Seeds: Dietary Zinc for Enhanced Immune Health 

Nuts and seeds offer more than just healthy fats, fiber, and protein; they’re also an excellent source of zinc. 

Zinc is the second most abundant mineral in the body and has numerous essential functions, one of which is the development and function of immune cells. 

While all nuts and seeds contain zinc, hemp seeds, pumpkin seeds, and cashews are particularly high in this mineral.

5. Green Tea: Antioxidant Properties for Immune Health  

While not technically a “food,” a list of immune-boosting foods wouldn’t be complete without green tea. 

One of the most powerful compounds found in green tea is an antioxidant called epigallocatechin gallate (EGCG). 

EGCG has been studied for its potential role in protecting against free radicals and treating certain diseases. It’s also been shown to potentially kill bacteria and ward off infection. 

Studies have also shown that consuming green tea may be effective in preventing influenza infections. 

Green tea also contains a high amount of L-theanine, an amino acid studied for its potential role in protecting against infections. 

6. Bone Broth: Nutritional Support for the Immune System

Bone broth isn't just a cozy drink — it's a research-backed immune booster. Packed with essential amino acids, collagen, and minerals like calcium, magnesium, and phosphorus, it supports a robust immune system. 

Studies indicate that glycine, the specific amino acid in bone broth, can better your body’s immune response and promote a healthy gut lining. 

Additionally, if you are sick, sipping a hot liquid can have a soothing effect on the respiratory system.

The Bottom Line

Incorporating these six foods can help boost your immune system; however, they aren’t a substitute for other lifestyle factors. 

To give yourself the best chance against catching a cold, make sure to maintain an overall healthy diet, engage in regular physical activity, get adequate sleep, drink only in moderation, and practice good hand hygiene.

 

Editorial Sources and Fact-Checking 

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• Vitamin C. National Institutes of Health Office of Dietary Supplements. March 22, 2021
• Oranges, raw, Florida. USDA Agricultural Research Service FoodCentral Data. April 1, 2019.
• Wiertsema SP, et al. The Interplay between the Gut Microbiome and the Immune System in the Context of Infectious Diseases throughout Life and the Role of Nutrition in Optimizing Treatment Strategies. Nutrients. Mar 9, 2021.
• Lopez-Santamarina A, et al. Probiotic Effects against Virus Infections: New Weapons for an Old War. Foods. Jan 9, 2021.
• Martens PJ, et al. Vitamin D's Effect on Immune Function. Nutrients. Apr 28, 2020.
• Vitamin B6. National Institutes of Health Office of Dietary Supplements. June 16, 2023.
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• Chicken. USDA Agricultural Research Service FoodCentral Data. April 1, 2019.
• Zinc. National Institutes of Health Office of Dietary Supplements. October 4, 2022.
• Liu, Jinbiao, et al. Epigallocatechin gallate from green tea effectively blocks infection of SARS-CoV-2 and new variants by inhibiting spike binding to ACE2 receptor. Cell & Bioscience. August 30, 2021
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• Chen S, et al. L-Theanine and Immunity: A Review. Molecules. May 1, 2023.
• Enrique Meléndez-Hevia, et al. Glycine can prevent and fight virus invasiveness by reinforcing the extracellular matrix. Journal of Functional Foods. 2021.
• Achamrah N, et al. Glutamine and the regulation of intestinal permeability: from bench to bedside. Curr Opin Clin Nutr Metab Care. Jan 2017.