Eat a rainbow of antioxidant-rich fruits and veggies to keep the whole family healthy this flu season.

Prevent the Flu with these Immune-Boosting Foods

Scientists have discovered thousands of healthy compounds in foods called antioxidants and phytochemicals that help protect our bodies from a host of diseases and conditions. Many of these compounds also provide the pigments that make plants a certain color. When you eat a “rainbow” diet full of plenty of colorful fruits, vegetables, beans and grains, you strengthen your immune system to help fight disease. Here are some of the key plant-based compounds that can help keep you cold and flu-free this season.


Found in: Onion, garlic, leek, chives, scallion
Color: White
The phytochemical allium helps keep your immune system healthy. Research shows allium also helps control hypertension and cholesterol and  may reduce risk of certain cancers.


Found in: Blueberries, blackberries, cranberries, strawberries, kiwi, plum, grapes, red cabbage, eggplant
Colors: Blue, purple, red
Among the strongest anti-inflammatory phytochemicals for strengthening the immune system, anthrocyanins are antioxidants that reduce inflammation


Found in: Carrots, winter squash, sweet potato, cantaloupe, pumpkin, citrus fruits, turnips, cauliflower, papaya, apricots
Color: Yellow, Orange, White
Rich in antioxidants, carotenoids enhance immune function, helping your body resist infection. Carotenoids are also important for eye health and good vision. And they may help slow the aging process, inhibit cancer cell growth, and improve lung function.

Catechins and Tannins

Found in: Black or green tea, wine, berries, cranberries, cocoa and chocolate
Color:  Red, green, and brown
Catechins and tannins are antioxidant phytochemicals that boost immune health, improve urinary tract health, and appear to reduce your risk of cancer and heart disease.


Found in: Apples, berries, cherries, grapes. kiwi, pomegranate, also lentils, peanuts, pecans, walnuts and other nuts and the spice turmeric.
Color:  Red, green, and white
Polyphenols are antioxidant powerhouses, which have been studied for their ability to lower cholesterol and reduce heart disease risk, prevent eye disease, strengthen the immune system, and decrease cancer risk.


Found in: Citrus fruits, apples, pears, cherries and many other fruits, also herbs such as sage, rosemary and bay.
Color: Green, yellow, orange
Terpenes are antioxidants that boost immune function and decrease inflammation. According to the American Institute for Cancer Research, terpenes may prevent or slow the growth of cancer cells.

Melanie Haiken writes about health, wellness and fitness for national magazines and websites. She specializes in discovering and reporting the latest research on diet, nutrition, fitness, weight loss and other health-related topics. Her award-winning stories have appeared in Fitness, Shape, Health, Forbes, and other respected magazines. She also contributes health stories to numerous Kaiser Permanente newsletters and other publications.