Can milk cause throat infection? An evidence-based guide

January 8, 2026 •

3 min read

For centuries, the belief has persisted that drinking milk exacerbates respiratory symptoms like mucus and congestion. This has led many to question, "can milk cause throat infection?" Recent medical studies, however, suggest that this link is more of a widespread misconception than a factual connection.

Quick Summary

This article explores the connection between milk consumption and throat health, addressing the common misconception that dairy is directly responsible for throat infections. It clarifies the role of milk's creamy texture in creating the sensation of thicker mucus, which is often mistaken for increased production. The piece presents a factual look at what the science says regarding dairy intake and respiratory illnesses.

Key Points

Not a Cause: Scientific evidence does not support the myth that milk directly causes throat infections or increases mucus production.
Sensory Effect: The sensation of thicker mucus is a result of milk's creamy texture mixing with saliva, not an increase in actual phlegm.
Allergies Are Different: For individuals with a diagnosed dairy allergy, consuming milk can trigger an inflammatory response, but this is a specific immune reaction, not a general effect.
Yogurt Can Help: Certain dairy products like probiotic-rich yogurt can be beneficial during an infection, offering soothing relief and immune support.
Avoidance is Unnecessary: Unless a specific intolerance or allergy is present, avoiding milk during an illness is not medically necessary and may lead to nutritional deficiencies.
Soothes the Throat: A glass of chilled milk or a warm milk beverage can sometimes soothe a sore throat and provide calories when appetite is low.

Debunking the Milk and Mucus Myth

The idea that milk and other dairy products increase mucus production is a deeply ingrained myth, with roots stretching back to the 12th century. Yet, decades of scientific research have consistently found no conclusive evidence to support this claim. The perception that milk creates excess phlegm is often a sensory effect, where the creamy texture of milk temporarily combines with saliva, creating a coating sensation in the mouth and throat. This feeling is frequently mistaken for an increase in actual mucus, especially when one is already congested from a viral or bacterial infection.

The Science Behind Milk and Mucus

Medical studies have attempted to prove the link between dairy and increased mucus, but have largely failed. A study in the American Review of Respiratory Diseases found no difference in nasal mucus production between groups of adults with colds who drank milk and those who didn't. Similarly, research on children with asthma showed no increase in respiratory symptoms after drinking milk versus a soy placebo. In reality, the body's mucus production is triggered by an infection or allergy, not by dietary intake.

The emulsion effect: Milk is an emulsion of fat in water. When it mixes with saliva, it can form temporary clusters or aggregates, causing a thicker, stickier feeling in the throat.
Not a trigger for production: While the sensation might make you feel the need to clear your throat more often, this doesn't mean your body is producing more phlegm.
A historical belief: The myth gained popularity partially through sources like Dr. Spock's baby manual in the mid-20th century, despite being based on anecdotal evidence rather than science.

Is Dairy Inflammatory for Everyone?

For the vast majority of people, dairy is not an inflammatory food and does not contribute to throat inflammation. A comprehensive review of 52 clinical trials found that, overall, dairy consumption was associated with an anti-inflammatory effect in individuals without allergies. However, there are exceptions, particularly for those with a pre-existing sensitivity or allergy.


Condition	Effect of Dairy	Notes
Healthy Individuals	Neutral to weakly anti-inflammatory	Dairy does not increase markers of chronic systemic inflammation.
Dairy Allergy	Pro-inflammatory	A true allergy can cause systemic inflammation and more severe symptoms.
Lactose Intolerance	Increased congestion or phlegm sensation	Digestion issues can trigger secondary respiratory issues in some sensitive individuals.
Respiratory Infections	No increase in mucus production	The creamy coating effect is a sensory illusion, not a biological increase.

Can Milk Aggravate a Pre-existing Condition?

While milk doesn't cause a new throat infection, it can affect the sensation of an already sore throat. The temporary thickening of mucus can feel irritating and lead to more throat clearing, which can further aggravate existing inflammation. Additionally, consuming very cold milk might trigger a cough reflex in some individuals due to the rapid change in airway temperature, not because of the milk itself. For those who find this sensation uncomfortable, switching to a lighter, less viscous liquid or a non-dairy alternative may offer relief without causing nutritional deficiencies.

What About Yogurt?

Interestingly, some dairy products like yogurt, especially those containing probiotics, can be beneficial during an infection. Yogurt is a soft, easy-to-swallow food that provides calories and nutrients when appetite is low. The probiotics can also help support the immune system. Warm milk with honey or a cool, soothing yogurt can provide comfort to a sore throat, debunking the idea that all dairy should be avoided.

Conclusion

In summary, the notion that milk can cause a throat infection is a medical myth unsupported by robust scientific evidence. A throat infection is caused by viruses or bacteria, not by what you drink. While the creamy texture of milk can create a temporary and harmless sensation of thicker mucus for some individuals, it does not increase the body's actual mucus production. Unless you have a specific dairy allergy or a confirmed lactose intolerance that affects your respiratory tract, there is no medical reason to avoid milk when you have a sore throat. In fact, a cool or warm glass of milk can provide soothing relief and much-needed nutrients during an illness.

For more detailed information on diet and inflammation, the National Institutes of Health (NIH) is an authoritative source. A helpful review of clinical evidence regarding dairy and inflammation can be found on their website.

Frequently Asked Questions

No, scientific studies have shown that milk does not increase the amount of mucus your body produces. The sensation of thicker phlegm is a sensory effect from milk's creamy texture temporarily coating the mouth and throat.

No, it is not bad to drink milk with a sore throat unless you have a dairy allergy or intolerance. Some people find that cool dairy products like milk or yogurt can be soothing, while warm milk can also provide comfort.

Milk does not make a viral or bacterial infection worse. While the thick feeling in the throat may prompt more throat clearing and feel irritating, it does not prolong or exacerbate the infection itself.

Some people report feeling more congested after drinking milk because its creamy texture combines with saliva, creating a temporary coating sensation in the mouth and throat. This feeling is often misinterpreted as increased mucus production.

Yes, children with a cold can safely be given milk. Since it provides important nutrients like calcium and vitamin D, restricting milk unnecessarily can have negative nutritional consequences. Staying hydrated is key during an illness, and milk contributes to hydration.

A true dairy allergy involves an immune system response that can cause severe symptoms like hives or swelling. Lactose intolerance is a digestive issue that might cause gastrointestinal symptoms and, in some sensitive individuals, a temporary increase in respiratory congestion.

For most people, avoiding milk will not significantly impact congestion. Congestion is caused by an infection or allergy, not dairy intake. People who believe milk causes mucus may report fewer symptoms when they avoid it, but this is often a placebo effect.