Your immune system protects you from harmful bacteria, viruses, and chronic diseases — and good nutrition is a key part of keeping your immune system healthy. Healthy, whole foods provide vitamins and minerals that your body needs to build immune cells, plus antioxidants that protect healthy cells.
A strong immune system depends on a wide range of nutrients that work together to keep you healthy. People who are poorly nourished have a higher risk of getting sick with colds and flu.
Start With a Well-Balanced Diet
A varied diet with plenty of lean protein, high-fiber carbohydrates, and healthy fats provides the tools your body needs to build and maintain a strong immune system. Adequate protein, a wide range of vitamins, and minerals — like zinc, selenium, copper, and iron — are crucial for immune system function.
Following a Mediterranean, DASH (Dietary Approaches to Stop Hypertension), or vegetarian diet can help you eat the right foods that provide these nutrients.
Don’t Skimp on Fruits and Vegetables
Colorful produce is rich in vitamin C, a key nutrient for stimulating immune cells. Fruits and vegetables are also packed with antioxidants that protect healthy cells, adding an extra layer of defense.
Aim for five to seven servings of fruits and vegetables each day, and try to vary your daily choices by choosing one fruit or vegetable from every color of the rainbow.
Consider a Multivitamin and Mineral Supplement
Most people can get the nutrients they need from a healthy diet. A daily multivitamin can help fill in the gaps (including vitamin D) if your diet isn’t optimal.
But you should skip the rest of the supplement aisle. According to the National Institutes of Health, taking very large doses of individual nutrients doesn’t appear to boost your immune system.
Include Cultured and Fermented Foods
Foods like yogurt, kefir, kimchi, sauerkraut, and fermented pickles provide probiotics, friendly bacteria that live in your gut. Probiotics help support your immune system and fight harmful bacteria and other microbes — especially those in your gut.
When choosing these foods, check the label to ensure they contain live, active cultures. Cultured dairy products have probiotics, but not all jarred brands of kimchi, sauerkraut, and pickles do. Try to eat at least one serving of these fermented and cultured foods daily. As an alternative, you can take a probiotic supplement.
Limit Alcohol, Sugar, and Packaged or Highly Processed Foods
Too many of these foods can weaken your immune system and make you more susceptible to viruses or other infections. They can also cause inflammation, increasing your risk of chronic diseases.
Try to limit desserts and alcohol to special occasions or once in a while. Choose whole foods instead of packaged meals and snacks when at the grocery store. And skip fast food like burgers, fried chicken, and French fries as much as possible.
Maintain Optimal Vitamin D Levels
This vitamin plays many important roles in your body, including regulating immune function. It’s naturally present in oily fish and egg yolks and added to fortified milk (regular and plant milk), orange juice, and cereals. If you don’t eat these foods daily, ask your doctor if you need a supplement.
The U.S. recommended daily allowance (RDA) for vitamin D is 600 IU (15 mcg) daily for adults 70 and under. Those over 70 should get 800 IU (20 mcg) daily. Your body stores vitamin D. You shouldn’t take more than the recommended amount unless your healthcare provider checks your vitamin D level and tells you to do so.
Maintain a Healthy Weight
Being significantly overweight increases your risk of developing chronic diseases like diabetes, heart disease, and cancer, and excess weight also makes you more susceptible to bacteria and viruses.
Having too much body fat, especially in your abdomen, promotes inflammation and impairs your immune cell function. Eating healthier, whole foods and cutting out junk food will help you lose weight.
Getting regular exercise also promotes weight loss, and it can help you maintain a healthy weight. Aim for at least 30 minutes of brisk exercise most days of the week.