Winter is an excellent time to have cold-fighting quick fixes (like elixirs and herbal remedies) on hand in case that tickle in your throat blows up. But building a strong, healthy immune system is also something you should think about year-round—like every time you sit down to a meal, say Elson Haas, MD, and Sondra Barrett, PhD, in their new book Ultimate Immunity.
How to do that? Eat diverse foods packed with nutrients that help bust inflammation and fortify cells.
"Regardless of the cause of any immune illness, inflammation is the underlying factor in almost all of the symptoms," write Dr. Haas and Dr. Barrett, and antioxidants like beta-carotene can help keep it in check, while vitamins like vitamin C support infection-fighting T-cells.
Scroll through to see the best foods to help your immunity:
Immunity boosting foods
Immunity boosting foods
Vitamin A Where to find it: In animal foods like eggs, fish oil, butter, and liver Why it’s important: “Vitamin A supports healthy tissue membranes, mucous membranes (like those in your mouth and nose), and cell membranes to keep them strong, which lessens your vulnerability to infectious organisms,” say Dr. Haas and Dr. Barrett. In other words, bring your vitamin A game to fend off the common cold. Other perks? It also has antioxidant and anti-inflammatory properties, they say.
Beta-Carotene Where to find it: Brightly colored fruits and veggies like papaya, carrots, and kale Why it’s important: Beta-carotene is in the same family as vitamin A and shares its antioxidant and anti-inflammatory properties that promote immunity. Cool fact: “Your body can convert beta-carotene into the amount of vitamin A that it needs—and when it has enough, it stops,” the MDs say.
Vitamin C Where to find it: Kiwi, citrus fruit, berries, and red peppers Why it’s important: This vitamin is always in the spotlight for preventing and fighting off a cold: That’s because Vitamin C supports infection-fighting T and B cell function, phygocytes (which literally devour harmful bacteria), plus healthy skin and wound healing, explain Dr. Haas and Dr. Barrett.
Vitamin E Where to find it: Spinach, sunflower oils and seeds, peanut butter, avocado, almonds, and wheat germ Why it’s important: Like vitamin C, vitamin E supports T and B cell functions and has anti-inflammatory and antioxidant properties. And in certain studies, it boosted response to vaccines, making them more effective against illness for older people, they explain.
Vitamin D Where to find it: Mushrooms, oily fish, egg yolks, and fortified milk Why it’s important: “Vitamin D may be a preventative panacea—protecting you from cancer, cardiovascular disease, dementia, and even the flu,” say Dr. Haas and Dr. Barrett. It also helps fight infection by activating T cells, producing antibodies and cytokines (the proteins that affect cell behavior), and quelling inflammation. Besides what’s on your plate, your body gets vitamin D when your skin is exposed to sunlight, so plan that morning run or 15 minutes of sunlight on a walk to grab lunch each day.
Vitamins B5, B6, and B12 Where to find them: To get your B5 and B6 vitamins, look to whole grains, nuts and seeds. For B12, eat animal foods like yogurt, liver, and beef; if you’re vegetarian, fermented foods like sauerkraut and tempeh contain small amounts, but Dr. Haas and Dr. Barrett recommend you take a supplement to meet your daily needs. Why they’re important: B5 and B6 get your antibodies working against infectious invaders, while B12 helps your body produce infection-fighting B cells and healthy red blood cells, they say.
Zinc Where to find it: Root vegetables, oysters, shellfish, seafood, and almonds Why it’s important: “Zinc is the most ‘immune-essential’ mineral, and a zinc deficiency puts you at risk for infections,” Dr. Haas and Dr. Barrett warn. Why? It works with vitamin E and selenium as a powerful antioxidant, enhances cell function, and helps your body make more infection-fighting antibodies. (That’s why so many cold meds contain it.) But take note: Excess zinc can actually decrease immune function, so don’t go overboard with supplementing.
Iron Where to find it: Lentils, leafy greens like spinach, meats, molasses, and raisins Why it’s important: Iron helps transport oxygen to all your cells, making it a key ingredient for energy production. “An iron deficiency may cause you to feel tired and have frequent infections,” Dr. Haas and Dr. Barrett explain. However, too much iron can prompt bacterial growth, so double-check your dosage with your doctor if you’re taking supplements.
Selenium Where to find it: Brazil nuts, nutritional yeast, brown rice, wheat germ, and salmon Why it’s important: According to Dr. Haas and Dr. Barrett, selenium is a key player when it comes to antioxidant activity. “[It] collaborates with vitamin E to produce the key antioxidant glutathione, which protects your cells from free radicals and supports detoxification,” they explain. Like zinc and iron, selenium must be taken in limited doses, so finding it in food is the way to go.
Magnesium Where to find it: Avocado, leafy greens, almonds, brown rice, and soy/tofu Why it’s important: You’re going to be hearing a lot about this buzzy mineral: Magnesium is an anti-inflammatory, plays a role in keeping the immune system strong, helps strengthen muscles and bones, and supports dozens of other functions, from cardiac and brain function to enzyme activity. (FYI: It’s also a key hormone regulator for women and low amounts can contribute in PMS and menopause symptoms.) Consider your avocado toast habit justified.