Soup can be very useful for colds because it is easy to digest, helps keep you hydrated, provides essential nutrients, and can help soothe a sore throat. The warm broth can also help clear nasal congestion and the steam can help open up blocked sinuses, providing relief from cold symptoms. Additionally, certain ingredients commonly found in soup, such as garlic, ginger, and vegetables, have immune-boosting properties that can help support your body's defenses during a cold.