When the weather starts to change, our bodies pick up on it!

So, if you're someone who gets "seasonal headaches," there's a scientific explanation. You might notice that your head hurts more often — especially when you wake up in the morning — at the start of a new season. This could have to do with your sinuses getting out of equilibrium, according to gastroenterologist Dr. Roshini Raj.

"It's a really interesting phenomenon," the doctor says. We all have sinuses, which are like pockets of air in our foreheads and in our cheek areas, she explains. Our sinuses have a certain pressure. 

The air outside, which is known as the barometric or atmospheric pressure, also has a certain pressure. 

"When the atmospheric pressure is the same as our internal pressure, we're good. But when the seasons change … there's a little bit of a mismatch between the pressure outside and what's in our body, and it takes a few days sometimes for that to equilibrate and that can trigger [headaches]."

This is the same reason why people sometimes get pain in their joints with certain weather changes, Dr. Raj adds. "It's the barometric pressure outside not matching with their pressure inside their body."

So, what can you do? The headaches shouldn't last more than a couple days, so you might want to stay indoors as much as you can just for those first few days, according to the doc.

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Also, with the days getting shorter, it can throw off your sleep cycle, the doc explains. And we all know that not getting enough sleep can cause headaches (at the very least!).

Talk to your doctor if you're experiencing significant and/or frequent headaches.