WE’RE CONSTANTLY HEARING about the importance of helping out our immune system. And, social media is full of advice for how to do that, from adaptogenic shots to apple cider vinegar to sleep hacks. Some of these #immuneboost tips are great, but others aren’t so great. (And you can’t really “boost” your immunity, as you’ll soon learn.)
Really, one of the best ways to keep your immune system healthy is also one of the simplest: by making sure you’re getting the right nutrients. The immune system is complex, though, and nutrition isn’t the only factor that heightens your immunity.
“Nutritious foods can strengthen the immune system—however, it would be somewhat flawed to say that any one vitamin, or special diet alone, could drastically improve one’s immune health,” says Marilyn Berger, R.D., a clinical dietician at CHA Hollywood Presbyterian Medical Center.
“The immune system is a bit more complicated than that,” she adds. “There are many other factors affecting immune health, such as physical activity, stress, age, and presence of medical conditions.”
The immune system is a network of organs, white blood cells, proteins, and chemicals that collaborate to protect you from bacteria, viruses, parasites, fungi, and other invaders that can make you sick. It has two parts: the innate immune system, which you’re born with, and the adaptive immune system that you develop as you’re exposed to microbes.
“There are definitely ways to improve your immune system,” says Louis Malinow, M.D., an internal medicine physician affiliated with MDVIP in Baltimore, Maryland. Vitamins, especially in supplement form, are just “one tiny crumb in what I consider the important components of boosting your immune system.”
But, if you’re looking to up your nutrient intake for your health, these are the best vitamins for your immune system.
The Best Vitamins for Your Immune System
Choosing nutrient-dense, whole foods provide most of the essential vitamins and minerals and properties to keep you healthy, Berger says. Here are the most important vitamins for your immune system:
Vitamin C gets a lot of attention for its immune-aiding properties, and it’s for good reason. It’s a powerful antioxidant that encourages the production of white blood cells, which protect you against infection. “It sort of bulletproofs the white blood cells,” Dr. Malinow says.
Your body doesn’t naturally produce vitamin C, though, so you need to include it in your diet, Berger says.
Food sources: Citrus fruits (oranges and grapefruits), berries, tomatoes, melon, broccoli, and bell peppers.
Vitamin E protects you from free radicals, which can cause illness, and helps the body fight off infections, Berger says. Research shows it’s one of the most important nutrients in immune function and helps your T-cells, a type of white blood cell, work at their best.
Food sources: Nuts (almonds and peanuts, especially), nut butters, seeds, wheat germ oil, spinach, mango, and kiwi.
Vitamin A keeps tissues in your stomach, intestines, respiratory system, mouth, and skin healthy, and helps you fight infectious diseases, Berger says. Beta carotene, found in orange, yellow, and leafy green vegetables, is a great source of vitamin A, and also supports eye health.
Food sources: Carrots, pumpkin, cantaloupe, butternut squash, leafy greens, fish oil, milk, and eggs.
Many people don’t get enough zinc, especially those who adhere to a plant-based diet since most zinc-rich food sources are animal products, Dr. Malinow says. It’s a mineral with anti-inflammatory and antioxidant properties, and research calls it the “gatekeeper of immune function.” Zinc may also have antiviral properties. However, zinc can be tough to absorb, so Dr. Malinow says when he prescribes it in supplement form, he pairs it with the antioxidant quercetin, which helps with absorption.
Food sources: Oysters, lean beef, blue crab, shrimp, turkey breast, pork, cheese, pumpkin seeds, yogurt, lentils, milk, and canned sardines.
Research shows that iron helps regulate the immune system. “Iron helps carry oxygen to cells and is a component of enzymes that are important for immune cell function,” Berger says. If you don’t get enough iron, your body can’t make the hemoglobin (a red blood cell protein) that you need to move oxygen through your blood vessels, and it might lead to anemia.
Food sources: Red meat, beans, seafood, nuts, and fortified cereals.
Vitamin D helps your immune system function properly and enhances immune cells. Deficiency can increase your risk of autoimmunity and increased susceptibility to infection, Berger says. Sunlight is one of the best sources of vitamin D.
Food sources: Milk, eggs, salmon, tuna, sardines, and fortified foods, like cereal and juice.
Vitamin B6 helps regulate the immune system. It spurs the production of white blood cells and T-cells that help your body fight bacteria, viruses, and other harmful substances. It also has anti-inflammatory benefits.
Food sources: Chickpeas, beef, salmon, tuna, chicken breast, fortified cereals, turkey, potatoes, and cottage cheese.
This mineral has been shown to rev up your immune system when it encounters an invader. Selenium also keeps your immune system from overreacting, Dr. Malinow says. This feature might protect you from chronic inflammation and certain autoimmune diseases, like Crohn’s disease.
Food sources: Eggs, Brazil nuts, tuna, and canned sardines.
When You Should Take Supplements
Eating lots of different food groups will help you get a variety of vitamins and minerals, which will maintain a healthy immune system, Berger says.
Food is the preferred way to ensure you get these nutrients. But, supplements may be necessary in some cases if your nutrient intake is limited, such as if you are a vegan or omit certain food groups.
“A single multivitamin supplement would be sufficient to fill in those gaps,” Berger says.
What Are Other Ways to Keep Your Immune System Healthy
What you eat and getting the right vitamins in your diet is just one piece of the puzzle in keeping your immune system healthy. There are several other things you should do to protect yourself.
Get Plenty of Sleep
“There are a thousand reasons that sleep is important, but one is immune health,” Dr. Malinow says, and you need at least seven hours a night. Research shows that being sleep-deprived can have a negative impact on your immune system and potentially increase your risk for illness.
Exercise plays a key role in your overall health, There’s evidence that physical activity can flush out bacteria from your airways, prevent bacteria from growing, cause positive changes in antibodies and white blood cells, and slow the release of stress hormones. Staying active also helps you sleep better and just feel better.
Drink Lots of Water
Hydration helps you stay healthy and keeps illnesses away, Berger says. Drinking plenty of water offers detox benefits, increases lymphatic drainage, and helps flush out waste. Men need 15.5 cups of water a day (and women need 11.5 cups).
Maintain a Healthy Weight
Obesity can raise your risk for a number of health conditions, like diabetes, some cancers, and heart disease. It also increases inflammation and impairs immune function. Eating healthy whole foods, exercising, and maintaining a healthy weight are crucial for immune health.
“Everybody’s chronically stressed,” Dr. Malinow says. “You’ve got deadlines. You’re up all night ruminating. When you’re stressed, you release cortisol.”
Cortisol is an immune suppressant, he adds. So, taking steps to reduce your stress levels will do wonders for your immune system.
Erica Sweeney is a writer who mostly covers health, wellness and careers. She has written for The New York Times, HuffPost, Teen Vogue, Parade, Money, Business Insider and many more.