Garlic
A proven common-cold buster, garlic is antibacterial, antiviral and antifungal. Research suggests it helps the body produce infection-fighting white cells and antibodies. Combine with other spicy foods, such as chili, hot mustard and radishes, to wage war on mucus.
Shiitake Mushrooms
Shiitake mushrooms contain AHCC (active hexose correlated compound), which may increase immune response to the flu virus. They have a meaty texture and add rich flavour to gravy, soups and stir-fries.
Salmon, Sardines and Mackerel
Wild-caught salmon, sardines and mackerel are an excellent source of vitamin D and omega-3 fats. These oily fish help protect against bacteria and viruses. Try them with lemon juice for an extra dose of infection-fighting vitamin C.
Sweet Potato
Sweet potato is rich in beta carotene, which converts into vitamin A, helping protect against infections in the respiratory system. Tastes great baked in its skin.
Grapefruit
There are 48 mg of vitamin C in one serving (1 small or large) of grapefruit-plenty for promoting white blood cell production. Eating this bittersweet citrus fruit increases our levels of glutathione, a powerful antioxidant that protects against winter illnesses. Makes a low-sugar, high-fibre dessert or breakfast option.