These are some healthy foods that you should add to your winter diet: Root Vegetables like carrots, turnips, radishes, beetroots, etc. Vitamin-D enriched foods like egg yolks, salmon, fortified cereals, milk, and red meat. Oatmeal Soup Mood-boosting snacks like sweet potatoes, beets, walnuts & roasted chickpeas Foodstuffs that enhance the immune system, such as citrus fruits, bell peppers, strawberries, kiwis, broccoli, and oranges.