If you’ve been sick recently and think the recent swings in temperature have something to do with it, you may be right.
As fall sets in, there have been fairly dramatic temperature changes, sometimes day to day, with one day cool and rainy and the next warm and sunny, with a more than 10-degree difference between the daily high temperatures.
Though respiratory infections do tend to pick up around this time, with children back in school and people spending more time grouped together indoors, it turns out that shifts in weather, humidity and air pressure all can increase the chance of developing an infection.
Dr. Megan McCarty, allergist and immunologist with Lehigh Valley Health Network, said this starts with your oral and nasal passages. Low humidity dries out the inside of your nose and mouth as well as the mucous membranes that provide normal protective barriers, increasing your risk of infection. She said small hair-like structures in your nose and mouth that help push out pathogens and foreign bodies also don’t function as well when temperatures fluctuate. When your body gets cold, your blood vessels constrict, trying to pool heat to the center of your body, which can also affect your immune system.
Rapid temperature fluctuations also interfere with the production of certain white blood cells. McCarty said that B cells, the ones in charge of making antibodies, can drop in number when days swing from hot to cold. The levels of other white blood cells in your bloodstream can also change.
Lastly, she said that when your body is cold, your body prioritizes maintaining temperature over other processes and this means your immune system may get the short end of the stick as your body tries to keep itself warm.
However, the immune system is not the only way the body can be affected by rapid weather changes. McCarty said high humidity can cause fatigue, joint pain and breathing difficulties. The low temperatures that cause your blood vessels to constrict also cause swings in blood pressure that can be especially bad for people who already have blood pressure issues. Changes in air pressure can affect the sinuses in our heads, causing inflammation, headaches and worsening allergies.
And no, your grandfather isn’t lying; he can tell if a storm is coming based on how his joints feel.
“People always say, ‘Oh, I can tell in my knees when it’s going to rain’ or something like that and it’s because the actual pressure of the atmosphere changes sort of the pressure within the joint capsules as well,” McCarty said.
For those with chronic illnesses, these kinds of weather changes can be particularly troublesome, especially those with asthma who may suffer flare-ups.
There are a few things people can do to help their bodies better deal with rapid temperature fluctuations, McCarty said. One is staying hydrated — the body needs water to function normally and even more so when temperatures are dry. Another is getting enough sleep; seven to nine hours, she said, is necessary to help maintain adequate immune system function.
“The other thing too is making sure that you get a lot of exercise,” McCarty said. “General blood flow, walking, that sort of thing, is helpful to circulate the blood and make sure that you’re clearing toxins or other things that have been pooled in your legs.”
She added that certain immune-boosting supplements may be helpful. She said zinc has the most evidence, but there is also some evidence for vitamin C and elderberry.
This story has been updated: Staying hydrated is one way to deal with rapid temperature fluctuations. A previous version mischaracterized that instruction.