Although mucus provides a valuable function in the body, when it is overproduced it becomes annoying. For instance, during a cold, asthma attack or allergies, mucus production often increases and becomes bothersome. For generations, people have believed there is a relationship between an increase in mucus and drinking milk. Although scientific evidence does not back the milk and mucus connection, it still persists.
Mucus is a thick fluid produced by various cells in the body. In addition to water and salt, mucus is made up of glycoproteins. Most people are aware mucus is produced in the throat and lungs, but it is also produced in the intestines, urinary track and reproductive organs.
Although mucus production may not seem that important, it does serve a needed function. Mucus protects the body from foreign substances. For instance, mucus in the nose helps trap irritants, such as dust and smoke, which prevents the irritants from entering the lungs. Mucus also clears sinus and nasal passages.
Another useful purpose of mucus is to prevent the tissues in the nose from becoming too dry and cracked, which can become uncomfortable. Although it is clear mucus serves a useful purpose, the problem is when it is overproduced during respiratory infections, sinusitis, allergic reactions and asthma attacks.
As reported by The Journal of the American College of Nutrition (JACN), research shows that mucus production is not increased by drinking milk. It is not clear exactly how the milk and mucus connection started, but the myth has persisted for generations. Some people may believe that the fat in the milk causes an increase in mucus production; however, this does not appear to be true.
Another explanation for why people think mucus is increased after they drink milk may be due to the coating milk can leave in the mouth. After drinking milk, a thick film may sometimes be left in the mouth and throat. Although the film or coating milk leaves behind may give the sensation of mucus, is it not actually an increase in mucus.
There does not appear to be any specific type of food that causes the body to produce more mucus. However, there are a few things which can increase the thickness of mucus and make it more difficult to get rid of. For instance, when a person becomes dehydrated, their mucus will become thicker and stickier. The thick consistency of mucus makes it more difficult to cough it up or have it drain from the nose. Certain beverages, such as those containing alcohol or caffeine can increase the chances of dehydration developing.
Although milk will not increase mucus, a few foods may actually help decrease the amount of mucus present. According to the University of Maryland Medical Center (UMMC), eating certain foods may help decrease mucus production in some instances, such as in individuals with cystic fibrosis. Recommended foods to eat include celery, pickles, watercress and cold water fish.
There is one exception to an increase in mucus when drinking milk. Individuals who have a milk allergy may experience respiratory symptoms after drinking milk, which may include an increase in mucus. According to the Cleveland Clinic, when a person has a milk allergy, he is usually allergic to some of the proteins in the milk. This causes a response from the immune system, which may include increased mucus, coughing and trouble breathing.
It is important to recognize the difference between a milk allergy and being lactose intolerant. People who have lactose intolerance have trouble breaking down the sugars in dairy products. The digestive system is involved and excess mucus production and coughing does not occur.
Although it may not be everyone’s first choice when they have excess mucus, drinking milk may actually help in some cases. The thickness or viscosity of mucus can change. When mucus is thinner it is often easier to cough up or expel from the nose or lungs. Staying well hydrated through drinking plenty of fluids, including milk can prevent mucus from becoming thick.
Milk also has several nutrients, such as vitamins A, B and D, along with calcium and protein, which can help a person fight off an infection or recover from one. Milk may also be the drink of choice for young children during an upper respiratory infection, such as a cold. In some cases, a sore throat may accompany an increase in mucus, such as with a respiratory infection or post nasal drip. Drinking a glass of cold milk may feel soothing to a sore throat.
The myth may still persist that milk will make mucus worse, but there appears to be scientific research concluding that milk will not cause an increase in mucus. In fact, if an individual feels like drinking a glass of milk when experiencing a respiratory infection, such as a cold, it may even be beneficial.