For centuries, people have believed there’s a link between drinking milk and producing mucus. Avoiding dairy products when suffering from a cold is common; people believe it reduces excess phlegm in their throats and nasal passages. It’s routine for professional singers, actors and public speakers to steer clear of milk before performances to keep their throats and vocal cords clear. Is it true that there's a milk-mucus connection, or could it be a persistent myth?
Medical research debunks the milk-mucus connection as a myth, disproving the notion that drinking milk increases mucous secretions. The consensus among studies concludes that milk makes mucus thicker because of its fat and viscosity, but it does not increase the amount of mucus produced. An article by Dr. Allen J. Dozer and Christina Lee in the "Archives of Pediatrics & Adolescent Medicine" states, “The belief has persisted for centuries that ingestion of milk causes excessive mucus, although the few studies on the topic have failed to demonstrate any effects of milk on mucus production.” Doctors say milk thickens saliva and mucus, coating the throat, which may give a person the sensation and perception of more mucus. “Although drinking milk may make phlegm thicker and more irritating to your throat than it would normally be, milk doesn't cause your body to make more phlegm,” said Dr. James Steckelberg, professor of medicine at Mayo Medical School. Furthermore, a study by the National Institutes of Health concludes that even when someone has a respiratory virus, drinking milk does not increase mucus production, although it may increase cough and congestion symptoms.
Except for Allergy and Asthma Patients
Studies on patients with allergies and asthma tell a different story than studies on milk and colds. Milk allergy patients may have increased production of mucus as an allergic reaction after consuming milk and dairy products. The New York University School of Medicine reports asthmatics have decreased lung function following consumption of whole milk, although drinking skim milk does not cause a decrease in lung capacity.
Mucus on a Mission
Mucus is actually good for our health. Secreted by mucous membranes, a lining of cells, mucus captures bacteria, viruses, fungi, dust, dirt, pollen, smoke and other environmental invaders. Mucus protects the skin from infection, damage and irritation. The water-based liquid (made of proteins, carbohydrates, salt and cells) protects the nose, throat and lungs and keeps tissues from drying out. The majority of our mucus ends up in our stomach, where acid takes care of the infectious invaders trapped within it. Nevertheless, excessive mucus in the throat and nasal passages is usually considered uncomfortable and unpleasant.