I've heard that you shouldn't drink milk when you have a cold because it increases phlegm. Is this true?
Answer From Julie Baughn, M.D.
No. Drinking milk does not cause the body to make phlegm.
Phlegm is thick, sticky mucus that's made in the lungs and upper airways. During a cold, mucus in the nose and throat gets thicker. It contains trapped germs and the proteins and cells the immune system sends to clear out the germs.
There aren't many studies on milk and mucus. But the ones we have suggest that our perceptions can fuel the belief that milk causes more mucus.
In 1948, about 600 people were polled on mucus and milk while seeing their health care provider, mostly for eye problems. The provider tested the mucus of patients who had greater complaints of mucus. Some drank milk and some did not. The conclusion was that milk is not the cause of increased mucus.
More-recent research suggests milk may play a trick on the senses that makes some people think it causes phlegm. When milk and saliva mix in the mouth, they create a somewhat thick liquid that can briefly coat the mouth and throat. The feeling that lingers may be mistaken for extra mucus.
One area that's been studied more is asthma.
Past research shows that children with asthma often stay away from milk because of the notion that it causes more phlegm. But a small study found that kids with asthma had no differences in symptoms whether they drank dairy milk or soy milk.
Reasons not to stop drinking milk
A glass of cold milk or a few bites of frozen yogurt may soothe a sore throat. It also could help you get some nutrients and calories when you might not feel like eating, such as when you're sick.
With
Julie Baughn, M.D.
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June 13, 2023
- Balfour-Lynn IM. Milk, mucus and myths. Archives of Disease in Childhood. 2019; doi:10.1136/archdischild-2018-314896.
- Koren Y, et al. Respiratory effects of acute milk consumption among asthmatic and non-asthmatic children: A randomized controlled study. BMC Pediatrics. 2020; doi:10.1186/s12887-020-02319-y.
- Cifelli CJ, et al. Association of yogurt consumption with nutrient intakes, nutrient adequacy, and diet quality in American children and adults. Nutrients. 2020; doi:10.3390/nu12113435.
- Lehtoranta L, et al. Role of probiotics in stimulating the immune system in viral respiratory tract infections: A narrative review. Nutrients. 2020; doi:10.3390/nu12103163.
- Marvels of mucus and phlegm. National Institutes of Health. https://newsinhealth.nih.gov/2020/08/marvels-mucus-phlegm. Accessed Jan. 26, 2023.
- Phlegm. National Cancer Institute. https://www.cancer.gov/publications/dictionaries/cancer-terms/def/phlegm. Accessed Jan. 26, 2023.
- Understanding mucus in your lungs. American Lung Association. https://www.lung.org/blog/lungs-mucus. Accessed Jan. 26, 2023.
- Common cold. Centers for Disease Control and Prevention. https://www.cdc.gov/antibiotic-use/colds.html. Accessed Jan. 26, 2023.
- Bennett JE, et al. Acute pneumonia. In: Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 9th ed. Elsevier; 2020. https://www.clinicalkey.com. Accessed Feb. 1, 2023.
- Moose RM. Does Milk "Make Mucus"? California Medicine. https://pubmed.ncbi.nlm.nih.gov/18731356/. Accessed Feb. 1, 2023.
- McGarvey L, et al. Global physiology and pathophysiology of cough. Part 2. Demographic and clinical considerations: CHEST expert panel report. Chest. 2021; doi:10.1016/j.chest.2021.04.039.
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As an enthusiast well-versed in respiratory health and related topics, I'd like to address the common belief that drinking milk exacerbates phlegm production during a cold. This misconception has persisted for years, with some attributing the notion to anecdotal experiences and traditional beliefs. However, let's delve into the evidence and expert opinions to shed light on the matter.
Dr. Julie Baughn, a reputable medical professional, debunks the myth that milk increases phlegm. According to her, phlegm is a thick mucus produced in the lungs and upper airways, and during a cold, mucus tends to get thicker due to the presence of trapped germs, proteins, and immune cells. Existing studies on milk and mucus perception have shown that our beliefs can influence our interpretation of the relationship between the two.
One study from 1948 involved polling around 600 individuals about mucus and milk while visiting their healthcare provider, primarily for eye problems. The conclusion drawn from analyzing the mucus of those with complaints was that milk is not the cause of increased phlegm. More recent research suggests that the sensation of increased mucus might be a result of a trick played on the senses when milk and saliva mix, creating a thick liquid that coats the mouth and throat.
The article also mentions research related to asthma, indicating that children with asthma might avoid milk due to the belief that it causes more phlegm. However, a study found no differences in symptoms between children with asthma who drank dairy milk compared to those who consumed soy milk.
To reinforce these insights, the article provides references to scientific studies published in reputable journals. For example, "Milk, mucus, and myths" from the Archives of Disease in Childhood (2019) and "Respiratory effects of acute milk consumption among asthmatic and non-asthmatic children" published in BMC Pediatrics (2020) contribute to the body of evidence supporting the claim that milk does not increase phlegm production.
In conclusion, the belief that drinking milk worsens phlegm during a cold lacks substantial scientific backing. While perceptions and anecdotes may persist, the available evidence suggests that milk does not cause an increase in phlegm. It's essential to rely on reputable sources and scientific studies to make informed decisions about dietary choices, especially during illnesses like the common cold.
References:
- Balfour-Lynn IM. Milk, mucus and myths. Archives of Disease in Childhood. 2019.
- Koren Y, et al. Respiratory effects of acute milk consumption among asthmatic and non-asthmatic children: A randomized controlled study. BMC Pediatrics. 2020.
