White blood cells are a key part of the immune system. These disease-fighters circulate through the body to fight bacteria and viruses, working to slow or stop the illnesses that these germs can cause. So it’s important to eat nourishing foods, especially those with protein, vitamin B12, and folate, to help make sure your immune system has enough white blood cells to do its job. While no one food is a silver bullet for optimal immune system function, these have been studied for their potential positive effects, including increasing white blood cells and fighting inflammation (as antioxidants can). Certain nuts and vegetable oils contain alpha-linolenic acid (ALA), which can only be acquired through foods. The body can convert ALA into EPA and DHA, but it’s more efficient to consume them in your diet. Omega-3s may also play an important role in the production of compounds that regulate immunity in the body and help protect the body from damage from over-reacting to infections. The best way to get the omega 3-fatty acids DHA and EPA is by eating fatty fish such as tuna, salmon, and mackerel. You can also get these omega-3s through krill oil capsules or algae supplements (which is a vegan source). Other sources of the omega-3 fatty acid ALA include flax seeds, flax oil, chia seeds, hemp seeds, and walnuts. Kid-friendly serving idea: Make canned wild salmon into salmon salad sandwiches or add anchovies or sardines to pasta sauce. Add a few spoonfuls of flax oil to an antioxidant-rich berry smoothie, make chia seed pudding, or make a yogurt parfait with fresh berries, granola, and a sprinkling of walnuts on top. The beneficial live cultures in yogurt, such as lactobacillus acidophilus, may help prevent colds and other infections or shorten their duration, although more research is needed. Yogurt can also be a good source of protein, which the body uses to make white blood cells. Kid-friendly serving idea: Spoon some plain yogurt into a bowl with berries and drizzle honey over it for a potent immune system boosting snack. Add plain yogurt to a smoothie, use plain yogurt in place of sour cream, or make a yogurt parfait with fresh berries, granola, and a sprinkling of nuts on top. Kid-friendly serving idea: Simmer some chicken vegetable soup or minestrone soup for a hearty dose of immune system-boosting antioxidants. It’s important to get a variety of fruits and vegetables of different colors because various types of carotenoids are thought to work together to strengthen the body’s immune system. Make it kid-friendly: Add roasted red peppers to pasta, offer multi-colored peppers for dipping into hummus, roast winter squash with cinnamon and ginger. Kid-friendly snack idea: Slather nut butter on whole wheat bread, celery, or an apple for an antioxidant-rich snack. One cup of strawberries contains as much as 100 milligrams of vitamin C, which is nearly as much as a cup of orange juice. Dark berries such as blueberries are especially high in bioflavonoids. For an optimal immune system boosting effect, eat a bowl of mixed berries, or vary which berries you choose from day to day, rather than eating just one type. Kid-friendly serving idea: Put lots of garlic into chicken noodle soup. Put some minced garlic into a Greek-style salad made with cucumber, tomato, and feta cheese. Make it kid-friendly: Slice up some shiitake mushrooms and add them to a stir fry or omelet. Use sauteed mushrooms as taco or burrito filling, or stir them into miso soup. The studies on cocoa are often done on extracts, although they may extrapolate the amount of extract used to a correlating amount of cocoa. Recent studies have also looked at cocoa as a whole and even dark chocolate. Studies have shown that regular consumption of cocoa/extracts may reduce heart disease risk, help raise good cholesterol, and possibly reverse blood vessel damage in people with diabetes. Make it kid-friendly: Add cocoa powder and mashed banana to oatmeal while it’s cooking, or make avocado-cocoa pudding. Try cocoa in savory dishes mixed with spices such as chili powder. Or, the classic: Have a mug of hot chocolate made with cocoa powder, milk, and a bit of sugar. Just one medium persimmon has about half of the recommended daily allowance of vitamin A, which has been shown to play a key role in the regulation of immune cells.

Other sources of vitamin A: Pumpkins, sweet potatoes, butternut squash, spinachOther sources of vitamin C: Strawberries, papaya, kiwi, cantaloupe, oranges

Kid-friendly serving idea: Kids love a good presentation. Cut up some persimmons, strawberries, and kiwi or other fruit and arrange on a plate in a fun, pleasing display.