Scientists finally figured out why we get sick in cold weather

Viral particles enter the nose in two ways: inhalation and direct contact.

“The nose is one of the first points of contact between the outside world and the inside,” he says. Dr. Benjamin BrierDirector of Otorhinolaryngology Translational Research at Mass. Eye and Ear and co-author of a study published in The Journal of Allergy and Clinical Immunology.

Once viral particles enter, the cells in the nasal cavity are rapidly activated and begin shedding the virus. However, new research results show that cold temperatures significantly impair this immune response.

To better understand what happens when a virus enters your nasal passages, let’s go back a few steps.

2018, Bleier with a team of scientists from Massachusetts Eye and Year and Northeastern University found When nasal cells in the front of the nose detect bacteria, they prompt the release of billions of tiny fluid-filled sacs.

These sacs, known as “extracellular vesicles” (EVs), travel quickly into the mucus to “enclose and attack bacteria before they have a chance to infect cells,” Bleier told Healthline. explained to

Basically, these EVs try to kill bacteria before they can cause a major infection in the body.

From here, researchers were encouraged to investigate further to find out what happens when the virus enters the nose.

Bleier explains:

They learned that for three common cold viruses, EVs are released and react in the same way: surrounding and attacking virus particles in the mucus.

“These vesicles contained molecules (called microRNAs) that killed the virus,” Bleier explained. This means that EVs “effectively cleared the virus before it bound to nasal cells and began infection.”

In addition, EVs also acted as ‘baits’, attaching viral particles to EVs instead of nasal cells.

But the investigation didn’t stop there. Bleier and his team hypothesized that this nasal immune response could be affected by cold air, as colds and flu are more common in the winter.

So they exposed nasal tissue to temperatures of 39.9°F or 4.4°C and found that doing so lowered tissue temperature by about 9°F or 5°C, which had a significant impact on the immune system. rice field.

“This drop significantly reduced the nasal innate immune response,” Bleier explained.

The number of EVs launched has dropped by more than 40%, and their quality has dropped significantly.

“This reduced response makes the virus more likely to stick to and infect nasal cells,” Bleier revealed.

Brier and his team believe the recent findings are significant.

“To our knowledge, this study is the first to provide a biological explanation for why people are more likely to develop colds, flu, and upper respiratory infections such as COVID-19 in colder temperatures. of,’ he said.

Unlike some other viruses, cold-related symptoms usually occur in one area of ​​the nose.

The most noticeable signs of the common cold AS Dr. Edward Quanis an ENT, Head and Neck Surgery, and Rhinology Specialist at UCI Health, California.

• stuffy nose and runny nose
• sneeze
• Postnasal drip

The latter can lead to sore throats and coughs, he told Healthline.

No one is immune to cold and flu pathogens, but some people have less ability to defend themselves against them.

Kuan revealed that these groups include:

• Young children because their immune systems are not yet developed
• People who live or work in densely populated or densely populated environments
• Individuals with a weakened immune system
• cancer patient
• who received a transplant

Dr. AS Abeer SiddiquiHe is a board-certified allergist and clinical immunologist in Houston ENT and Allergy.

She said this nutrient has been shown to boost our mucous membranes (primary nasal tissue) and overall immunity.

She revealed that vitamin C functions as a powerful micronutrient, antioxidant, and cofactor (or “helper”) for the body’s enzymes. And these enzymes are important. [our] Innate immune cells, including white blood cells. ”

In general, Siddiqi continued, “Vitamin C helps support immunity in every part of the body that has a dense network of immune cells and tissues.”

Nutrients are readily available in many forms food Oranges, broccoli, red peppers, etc.

Besides vitamin C, basic hygiene measures can also prevent disease, says Siddiqi. These include:

• hand wash
• hand sanitizer
• Wear a quality face mask (especially in crowded areas)
• cover your mouth when you sneeze or cough
• Isolation when sick

The new research is crucial in helping us better understand how our bodies respond to viruses in different environments and explore potential treatments.

“We hope that our findings will lead to therapeutic approaches to enhance the innate immune response in the nasal cavity or to increase the number of extracellular vesicles, such as through nasal sprays,” Bleier said. increase.

Until then, taking precautions like taking vitamin C and wearing a mask in crowded places can help protect your nose and keep you warm on cold days.