The question of whether to consume milk or other dairy products while suffering from a sore throat is a common health concern. Many people believe that drinking milk can worsen respiratory symptoms by causing the body to produce more phlegm or by thickening existing mucus. This widespread belief often leads individuals to completely avoid dairy when they are ill with a cold or an upper respiratory infection.
Dairy and Mucus: Separating Myth from Reality
Scientific research generally does not support the belief that drinking milk increases the production of respiratory mucus or phlegm. Studies have found no correlation between dairy intake and an increase in symptoms like congestion or the total weight of nasal secretions produced. The physiological mechanism for dairy to trigger excess mucus production is simply not present for most people.
Research involving children, including those with asthma, found no difference in breathing symptoms or lung function after consuming either dairy milk or a soy milk substitute. These findings suggest that the concerns are often based on anecdotal experience rather than on an actual physiological response to milk ingestion. For the majority of the population, the consumption of milk does not affect the amount of mucus secreted by the body when sick.
Phlegm is produced by the respiratory tract to trap pathogens and clear the airways, a process that is largely independent of dietary intake. Milk is a source of protein, calcium, and calories, and avoiding it during an illness can lead to reduced nutritional intake when the body needs it most. Therefore, unless a person has a diagnosed cow’s milk allergy or lactose intolerance, there is no scientific reason to eliminate milk when dealing with a sore throat.
The Sensory Experience: Why Dairy Feels Thicker
Even though milk does not increase mucus production, many individuals feel a noticeable difference in their throat after consuming it. This perceived thickening is often described as a coating sensation and is more of a sensory experience than an actual change in mucus volume or viscosity. This effect is due to the physical properties of milk, particularly its fat content and creamy texture.
When milk mixes with saliva in the mouth and throat, it forms a temporary, harmless emulsion. This thin film briefly coats the throat lining and existing mucus, making the mucus feel momentarily thicker or harder to swallow. This lingering sensation is frequently mistaken for an increase in phlegm or congestion.
The feeling can be more pronounced with whole milk or other high-fat dairy products, which leave behind a more substantial residue. This effect is similar to the “mouth-feel” experienced when consuming other viscous liquids. The perception of increased thickness can lead to more frequent throat clearing or coughing, reinforcing the belief that dairy is worsening the illness.
Optimal Hydration for Throat Relief
Focusing on overall hydration is a more effective strategy for managing a sore throat than worrying about dairy consumption. Drinking sufficient fluids is important because it keeps the throat tissues moist and helps to thin out existing mucus secretions. Thinner mucus is easier for the body to clear, which can alleviate irritation and discomfort.
Water, clear broths, and decaffeinated herbal teas are excellent choices for maintaining hydration during an illness. Warm liquids often provide a soothing effect on irritated throat tissues. Adding honey to warm tea can also help to coat the throat and offer temporary cough relief.
It is helpful to avoid beverages that can cause dehydration or further irritate the throat lining. Caffeine and alcohol are mild diuretics, which can reduce the body’s overall hydration level. Highly acidic beverages, such as citrus juices, may cause a burning sensation on inflamed throat tissue.