Why Is Immunity Lower In Winter?
The winter months often come with a barrage of more frequent colds and flus. But you don’t have to resign yourself to a season full of sickness just because it has always been that way!
The first step in keeping yourself safe from pesky winter illnesses is understanding exactly why they seem to hit hardest in the winter months, and knowing how to combat them before they occur. So why is immunity lower in winter? And what can you do about it? Read on to find out.
Does winter lower the immune system?
Wintertime does lower the immune system. It has been long thought that illness rates rise during the winter months for reasons not related to biology, but studies done in recent years have found a few connections that paint a different picture.
For example, Yale scientists began a study in mice to help determine just how cold weather affected them biologically while they were simultaneously exposed to a cold virus. The study itself found that cold weather in and of itself lowered the body’s defenses in the airways and the nose. When the mice were exposed to different temperatures and the same virus, those that were out in the cold experienced symptoms from the virus more often and more severely than those who were not.
The airways and nasal passageways act as a first defense system in the sense that they are meant to “catch and contain” many viruses before they get further into the body to cause illness. However, nasal passages and airways that are colder in temperature are not able to fight off pathogens as well as they should be. Although the reasons behind the overall weakened action of the immune function during winter aren’t yet entirely clear, it has been confirmed that cold weather can allow viruses to infiltrate the body more easily.
Another biological reason for lowered immunity in winter has to do with vitamin D and sunshine exposure. Vitamin D plays a vital role in many of the body’s processes, and humans get a lot of their stores from the sun. Since the winter months feature shorter days and less sunshine, many people have a lowered intake of this essential nutrient. And when there’s too little vitamin D in the body, the immune system just doesn’t function as it should.
Having lowered immunity not only puts you at risk of contracting a cold or flu infection this winter – it can also put you at risk of other infections, or at risk of developing chronic diseases that can sometimes occur when a person’s immune system isn’t functioning properly over a longer period of time.
Why is it easier to get sick in the winter?
Aside from the biological reasons that people get sicker more often in the winter, there are other factors that are seemingly more difficult to counter. For example, people are often crammed into spaces more tightly in the winter because there is less of an inclination spend time outdoors. Crowded public transportation and indoor venues make the spread of viruses much more prolific. Virus droplets in the air are breathed in more easily by others because people are closer together than they usually would be.
Another reason that it’s easier to get sick in the colder months is because of the winter viruses themselves and the way they survive. Colder and drier conditions, like those seen throughout the winter months, are prime conditions for viral pathogens. They survive best in this type of weather, making them stronger and more of a threat than they are in the warmer months.
How can I keep my immune system strong in the winter?
According to the Centers for Disease Control and Prevention, the best way to avoid getting sick in the winter is by practicing good hygiene when it comes to washing your hands. Make sure you wash for at least 20 seconds with warm water and soap after touching things such as handrails, elevator buttons, or anything else that other people come into contact with. If there are no washrooms available to wash your hands, keep hand sanitizer on you to help rid yourself of germs.
Viruses are not likely to get into your body by simply being on your hands, but humans tend to touch their faces an average of 16 times every hour. If the virus on your hands is then transferred to your face, it can invade your body and cause illness. Avoid touching your face and keep washing your hands to help keep viruses at bay. Another CDC tip is avoiding others who are ill. (Prior to the COVID-19 pandemic, this advice may have been taken lightly, but the tables have turned in the last two years!)
The other most effective way to keep yourself healthy in the winter is to keep your immune system strong and ready to fight off any attacks. You can do this by:
- Eating a well-balanced diet full of the nutrients your body needs
- Getting good-quality sleep for roughly eight hours per night
- Keeping your nasal passages warm while outside by wearing a scarf or mask
- Exercising regularly
- Taking supplements if you feel you are not getting enough vitamins through your diet
Unfortunately, there isn’t much you can about the biological effects winter has on the body and the immune system – but there are ways you can avoid cold or flu and keep yourself healthy until spring rolls back around!