Eating a well-balanced diet benefits the body in many ways. When we choose foods like lean protein, fruits, vegetables, and whole grains, they can help prevent chronic health conditions like heart disease, diabetes, and obesity. But there is another reason to consider what you put on your plate. A nutritious diet can help fight illness by boosting the immune system. The immune system is the body’s natural defense system against infection, bacteria, and disease. A well-functioning immune system prepares the body to better fight illness, if the immune system is weakened, you’re more likely to get sick.
Poor nutrition is one of the most frequent reasons that the immune system malfunctions. Inadequate intake of nutrients affects the immune response depending on which vitamin or mineral is deficient and to what extent it is missing from the diet. There is no “one superfood” that can do it all, but there are many nutrients that can enhance the immune system. Here are some natural sources to help you come out on the winning end of cold and flu season.
Vitamin A This vitamin is called the anti-infective vitamin because it functions in the development and maintenance of the body’s barriers to infection, thereby decreasing the risk of illness. Vitamin A stimulates the immune system and works as an antioxidant in maintaining optimal immune function.
Find it in:
• Leafy greens such as kale, spinach, cooked collards, cooked turnip greens, Swiss chard, Brussel sprouts and broccoli
• Yellow/Orange vegetables such as carrots, pumpkin, winter squash, sweet potatoes, and summer squash
• Tomatoes
• Cantaloupe, watermelon, tangerine, mango, apricot, papaya, nectarine, guava
• Bluefin tuna, trout
• Cheese such as blue, feta and cheddar
Vitamin C This vitamin strengthens the immune system by increasing the production of B-and T-cells and other white blood cells that help fight infection. Vitamin C works as antioxidant to help increase white blood cells’ ability to destroy disease causing microorganisms.
Find it in:
• Citrus fruit such as oranges, grapefruit, strawberries, kiwi, papaya, mango, and star fruit.
• Vegetables: Broccoli, spinach, kale, bell peppers, tomatoes, butternut squash, russet potatoes, snow peas and Brussels sprouts
Vitamin D This vitamin assists the regulation of normal immune function, and boosts the production of immune cells
Find it in:
• Salmon, Tuna, Swordfish, Sardines
• Cod liver oil
• Vitamin D fortified foods such as milk, tofu, yogurt cheese and orange juice
• Eggs
• Mushrooms
• Beef liver
Vitamin E The main function of this vitamin is as an antioxidant, which helps to protect the body from damage due to free radicals.
Find it in:
• Nuts and seeds such as almonds, pine nuts, Brazil nuts, sunflower seeds, hazelnuts, and peanuts.
• Whole grains such as barley, millet, farro, brown rice, steel cut oats, whole wheat bread, whole wheat pasta
• Avocado
• Artichokes
Zinc This mineral increases levels of some antibodies and immune cells, such as T-lymphocytes. Zinc also inhibits the growth of disease-causing bacteria.
Find it in:
• Oysters
• Shellfish
• Chicken
• Tofu
• Legumes
• Seeds such as hemp, sesame, and pumpkin
• Nuts
• Lentils
• Yogurt
• Mushrooms
Iron This mineral strengthens the immune system by promoting growth and activity of immune cells which increases resistance to colds, infection, and disease. Iron also carries oxygen to immune cells.
Find it in:
• Beef, chicken, seafood, and turkey
• Canned light tuna and sardines
• Beans, lentils
• Tofu
• Dried fruits such as apricot, prunes, raisins
• Prune juice
• Enriched breads and cereals
• Broccoli
• Nuts
Selenium This mineral enhances the activity of immune cells, assists in detoxifying the body of heavy metals that suppress the immune system
Find it in:
• Brazil nuts
• Tuna
• Sardines
• Turkey
• Eggs
• Cottage Cheese
• Brown Rice
• Sunflower seeds
Folic Acid This vitamin is also known as Folacin or Folate. Its main function is to maintain the cells’ DNA and regulate cell division. Folic acid also produces antibodies which help fight infection
Find it in:
• Enriched foods such as pasta, bread, rice, and cereal
• Wheat germ
• Eggs
• Leafy greens such as spinach, kale, turnip greens, romaine lettuce, arugula
• Broccoli, Brussel sprouts, beets
• Grapefruit, oranges, lemon lime
• Avocado
• Peanuts
• Sunflower seeds
Omega 3 Fatty Acids Omega 3’s are most widely known as essential to brain health, and cardiovascular function but they also help the immune system by reducing inflammation and enhances the function of immune cells.
Find it in:
• Fish such as salmon, mackerel, anchovies, sardines, and herring
• Walnuts
• Soybeans
• Flaxseed and Chia seeds
• Flaxseed oil
• Hempseed oil
Garlic Contains substances that inhibit the growth of bacteria and can stimulate the immune system. To get the immune boosting properties from garlic, try adding to soups, stews, sauces and stir fry.
Other natural ways to improve the immune system include:
• Exercise regularly. The Physical Activity Guidelines for Americans recommend healthy adults get 150 minutes of moderate-intensity activity and 2 days of strength training per week. To reach 150 minutes, aim for to 30 minutes of movement 5 days a week. For strength training try lifting weights, working with resistance bands, using your own body weights such as pushups, squats, lunges, and planks.
• Get adequate sleep. The National Institutes of Health recommends the average adult needs between 7-8 hours a night. Deep sleep stimulates and energizes the immune system.
• Drink alcohol in moderation. Heavy drinking can suppress the immune system. Moderate alcohol consumption, one drink per day for women and two drinks per day for men has not shown negative benefits on the immune system
• Manage stress. Stress hormones can turn off disease fighting white blood cells or trigger a hyperactive immune system which increases the risk of developing auto immune diseases.
• Quit smoking. Toxins found in cigarette smoke can interfere with immune cells and disrupt antibody production
Content submitted by Janyce Gately – MS, RD, LDN, CHWC