If you want a strong immune system to fight off the flu and the cold during winters, then include cauliflower in your diet. It’s antiinflammatory in nature and rich in antioxidants. The key ingredient to fight the flu and cold is Vitamin C, which cauliflower contains in plenty. Go for cauliflower, which is tightly packed with no brown spots. Cauliflower soup is the ideal healthy meal for a cold day.