3 Surprising Foods That Fuel Your Immune System

Cold and flu season, combined with an ongoing pandemic, is motivating many Americans to do everything possible to support immune health. Fortunately, simple lifestyle habits, like a healthy diet, can make a big difference in strengthening the body’s defense system. But what foods are best — and why?

When it comes to immune-boosting foods, most people immediately turn to orange juice for a quick fix of vitamin C. “While it is true that citrus fruit helps support the immune system, there are many other foods that offer an impressive profile of nutrients believed to maintain strong immunity,” says registered dietitian Sheri Kasper. Here are three surprising, dietitian-recommended foods that can help ward off illness this cold and flu season.

Farmed salmon

Farmed salmon offers outstanding nutrition that can help protect against everything from heart disease to depression. Specifically, farmed salmon supports the immune system thanks to two key nutrients that are uncommon in many other foods: vitamin D and omega-3 fatty acids. While vitamin D is often connected to bone health, emerging research out of Boston University suggests that it may also be vital to proper immune function.

Few foods are naturally high in vitamin D, but a serving of farmed salmon offers nearly one-third of daily recommended needs. Omega-3 fatty acids, abundantly found in farmed salmon, are highly anti-inflammatory and support the immune system by reducing chronic inflammation. Kasper recommends choosing farmed salmon from Chile because it is sustainably raised, high in omega-3 fats and does not contain antibiotics or mercury.


Yogurt and other fermented foods contain healthy bacteria called probiotics. Probiotics are well-known for supporting digestive or “gut” health by preventing overgrowth of bad bacteria. But maintaining a healthy balance of good and bad bacteria in the gut is also believed to boost the immune system.

“Most people do not realize that about 70 percent of your body’s immune system is in your gut,” says Kasper. In addition to containing probiotics, yogurt is also one of the few foods that is almost always fortified with vitamin D, which offers additional immune support. Look for yogurt labeled as containing “Live and Active Cultures” and steer clear of yogurt that contains a lot of added sugar. Try plain yogurt and sweeten by adding fresh fruit and a small drizzle of honey.

Red bell peppers

Red bell peppers are rich in vitamins and antioxidants that support the immune system. One example is vitamin C, which encourages the production of the white blood cells that are responsible for defending the body against pathogens. Red bell peppers contain almost three times more vitamin C than oranges.

They are also loaded with vitamin A and the antioxidant beta-carotene, which can be converted to vitamin A in the body, when needed. Vitamin A is important in maintaining the natural mucus barriers located in the eyes, gut and other parts of the body. These barriers are designed to trap bacteria and are essential to optimal immunity. Be sure to choose red peppers because they have significantly more vitamin A, vitamin C and beta-carotene compared to green bell peppers.

While a healthy diet cannot prevent seasonal colds, the flu or other viral illnesses, a combination of the right foods, plenty of sleep, regular exercise and a balanced lifestyle will arm your body’s defenses and may help minimize the length and severity of illness. For more information about salmon and wellness, visit chileansalmon.org.

Author Profile

The Editorial Team at Lake Oconee Health is made up of skilled health and wellness writers and experts, led by Daniel Casciato who has over 25 years of experience in healthcare writing. Since 1998, we have produced compelling and informative content for numerous publications, establishing ourselves as a trusted resource for health and wellness information. We aim to provide our readers with valuable insights and guidance to help them lead healthier and happier lives.