I don't have a cold, so why do I suddenly become a "snotty nose"?

Have you ever had this experience? On a slightly cold morning, after getting up and wearing plenty of clothes, you often have a stuffy nose or even a runny nose. These symptoms are also likely to occur when you go out into the cold.

How come I suddenly have a snotty nose even though I don't have a cold? To understand why, we need to first understand the mechanism of snot formation.

Image source: pixabay

1. Mechanism of nasal mucus formation

A runny nose is actually a protective mechanism of our body. It can prevent the nasal mucosa from drying up, making the air inhaled into the lungs moist and warm, protecting the lungs from irritation. At the same time, because of the moisture, it can stick to harmful substances such as dust, microorganisms and germs in the air.

There is also a lysozyme in the nasal mucus that can dissolve bacteria, so a small amount of low-level bacteria is blocked in the nasal cavity. A healthy nasal cavity has a complete mucous membrane, and the mucus line under the mucosa is constantly secreting mucus. A normal person can secrete hundreds of milliliters of mucus every day. Due to evaporation and drying or flowing to the nasopharynx, it enters the stomach through swallowing, so we generally cannot see mucus flowing out of the nasal cavity.

2. What causes an uncomfortable stuffy nose?

When a large number of viruses invade the human body, our immune system will produce corresponding antibodies to eliminate these germs. There are a large number of mast cells distributed in the nasal mucosa. These cells contain active substances that block ammonia. Once antibodies and germs combine, they will stimulate mast cells to release ammonia and stimulate the mucosa to secrete more mucus, which is nasal mucus.

When a cold or rhinitis occurs, it is actually the invasion of bacteria. At this time, the nasal mucosa is stimulated and the defense mode is turned on. The amount of nasal mucus secretion will suddenly increase, and the bacteria will be carried away with sputum or nasal mucus. A large amount of nasal mucus is secreted, and the water in the nasal cavity is also lost in large quantities, and the nasal mucus becomes sticky. At the same time, the bacteria cause local swelling of the nasal cavity. The air leading to the nose is like being stuck, and nasal congestion is formed.

If you have a runny nose even though you don't have a cold, it's because the nasal mucosa is stimulated by the dry and cold air, and the body activates a defense mechanism to maintain the humidity and temperature in the nasal cavity. The runny nose looks and sounds a bit uncomfortable, but when you think that they are protecting us, don't you feel less uncomfortable instantly? Of course, a runny nose and a stuffy nose are still uncomfortable. We can take medicine to relieve the symptoms of a runny nose when we have a cold.

3. How to relieve symptoms?

How should we deal with a runny nose even though we don't have a cold? Here are some tips to help you easily deal with a runny nose in cold weather.

1. Rinse your nasal cavity with saline solution. Use about 240 ml of warm water and 1/2 tea of ​​Sanken to make it. You can also buy nasal rinse solution at the pharmacy. This type of liquid can wash away nasal mucus, help you open your nasal cavity, and breathe more smoothly. Be careful not to inhale it into your lungs when washing to avoid choking.

2. A cup of hot drink can help relieve nasal congestion. You can give yourself a cup of hot drink when you get up to relieve the symptoms of nasal congestion and runny nose.

3. Steam also helps break up nasal mucus and relieve congestion. You may want to take a hot shower after getting up or place a humidifier in the bedroom.

4. When the weather gets colder, wearing a mask or scarf can also protect against the invasion of cold air and prevent irritation of the nasal cavity. If you are allergic to the material of the scarf or mask, please choose carefully.

If you have a runny nose even though you don't have a cold, it's probably just a defensive reaction of your body to low temperatures. Don't worry too much. I hope these tips can help you get rid of your runny nose.

The article is produced by Science Popularization China-Starry Sky Project (Creation and Cultivation). Please indicate the source when reprinting.

Author: Zong Weimin, a popular science writer

Reviewer: Chen Gang, Chief Physician, Department of Otolaryngology, Beijing Friendship Hospital, Capital Medical University