Consider a diet rich in vitamins A, C and E, as well as the mineral zinc. Foods containing these vitamins are believed to help support the immune system! Vitamin A can be found in carrots, mango, tuna, sweet potatoes and butternut squash. Foods rich in vitamin E include sunflower seeds, nuts such as almonds and hazelnuts, green leafy vegetables such as spinach and kale, avocados, squash, and kiwi. You can get your daily vitamin C from citrus fruits, broccoli, green peppers, tomatoes, and strawberries. The mineral Zinc is found in beans as well as whole grains such as barley, brown rice, oats, and quinoa. As a bonus, try to reduce your intake of added sugar (e.g., soda, candy) because excessive sugar impairs the immune response.