Many people believe that eating dairy increases the amount of mucus your body produces. They say that drinking milk when you have a cold will make you feel even more congested. But is this true? A team of researchers did a study to find out. They found that people with colds who drank milk did not produce more mucus. But some people did feel more congested. Why is that? Milk is an emulsion. When it combines with the saliva in a person’s mouth, it can make the saliva droplets stick together. This could create the thicker feeling some people experience.