The marvelous powers of mucus
It's snot just a pesky cold symptom


While we may think of mucus as merely the slimy substance that clogs our nose and gets blown into a tissue, it's so much more. It lines several body organs, acting as a first line of defense against foreign invaders, as well as aiding essential body functions like digestion and illness prevention. And now scientists are taking inspiration from mucus for new disease-fighting treatments.
What is mucus made of?
Mucus is made of more than 95% water by weight, but its "key building blocks are mucins, which are long proteins decorated with complex sugars that make them look like bottlebrushes," said The New York Times. These mucins "attract and retain water, giving mucus its slippery, gel-like consistency," said New Scientist. This allows the mucus to keep the passages wet. "Once secreted, mucins crosslink with themselves and other compounds, creating a meshlike configuration," and the "more mucins in mucus, the denser this network becomes, resulting in smaller gaps or pores in its structure."
What can mucus do?
Mucus is a "masterpiece of biological engineering in my mind," said Katharina Ribbeck, a professor of biological engineering at the Massachusetts Institute of Technology, to the Times. It serves several purposes, from protecting us from pathogens to helping with digestion. "We are actually now learning more and more that it is very dynamic," said David Thornton, a biochemist at the University of Manchester, to New Scientist. "It is not just an inert barrier."
Subscribe to The Week
Escape your echo chamber. Get the facts behind the news, plus analysis from multiple perspectives.

Sign up for The Week's Free Newsletters
From our morning news briefing to a weekly Good News Newsletter, get the best of The Week delivered directly to your inbox.
From our morning news briefing to a weekly Good News Newsletter, get the best of The Week delivered directly to your inbox.
The goopy substance protects the human body in two ways by being both a physical barrier and a chemical barrier. It works by "shielding the body from unwanted objects and molecules," as well as "actively interacting with foreign materials," said New Scientist. "Mucus is almost like a bouncer at an exclusive nightclub, deciding who gets through." But that's not all it does. Mucus has an "important role in helping to smell, reproduce and have proper gut health, but it also plays an important role in how drugs are absorbed in the body," said Northeastern Global News.
It also "lines all our wet epithelial surfaces," Rebecca Carrier, a chemical engineering professor at Northeastern University, said to Northeastern Global News. This includes the nose, eyes, ears, throat, lungs, stomach and urological and genital tracts and more. Its composition and consistency on these different surfaces can vary as needed. For example, "human cervical mucus becomes thinner and more watery during ovulation, enabling sperm to penetrate it more easily," said New Scientist. "It might even respond to our body's internal clocks."
How can mucus help further medicine?
Researching how mucus works could open exciting possibilities in medicine. For example, mucins contain sugar molecules called glycans that can uniquely fight pathogens. Rather than killing them, the glycans are a food source for the bacteria. It's "like giving a kid a lollipop. They will calm down. Usually, they stop fighting," said Ribbeck to New Scientist. Treating the microbes this way "seems to tame them, rendering them less harmful." As a result, "one strategy could be to use glycans themselves, or molecules mimicking them, as alternatives to antibiotics or immunotherapies." This could also work without creating drug resistance, as can happen with antibiotics.
A free daily email with the biggest news stories of the day – and the best features from TheWeek.com
Devika Rao has worked as a staff writer at The Week since 2022, covering science, the environment, climate and business. She previously worked as a policy associate for a nonprofit organization advocating for environmental action from a business perspective.
-
Illicit mercury is poisoning the Amazon
Under the Radar 'Essential' to illegal gold mining, toxic mercury is being trafficked across Latin America, 'fuelling violence' and 'environmental devastation'
-
Israel faces international anger as Gazans starve
Feature World leaders pressure Israel to let in aid as famine spreads across Gaza
-
Redistricting: How the GOP could win in 2026
Feature Trump pushes early redistricting in Texas to help Republicans keep control of the House in next year's elections
-
Scientists are developing artificial blood for use in emergencies
Under the radar It could aid in global blood shortages
-
Babies born using 3 people's DNA lack hereditary disease
Under the Radar The method could eliminate mutations for future generations
-
Not just a number: how aging rates vary by country
The explainer Inequality is a key factor
-
Children's health has declined in the US
The Explainer It's likely a sign of larger systemic issues
-
Cytomegalovirus can cause permanent birth defects
The Explainer The virus can show no symptoms in adults
-
Deadly fungus tied to a pharaoh's tomb may help fight cancer
Under the radar A once fearsome curse could be a blessing
-
Kennedy's vaccine panel signals skepticism, change
Speed Read RFK Jr.'s new vaccine advisory board intends to make changes to the decades-old US immunization system
-
A disproven medical theory could be guiding RFK Jr.'s health policy
The Explainer The miasma theory is one of the oldest medical beliefs in history