Remember when your grandma used to say that she knew when a storm was coming because she could "feel it in her bones"? It turns out that she may not have been as crazy as you thought. Changes in barometric pressure that accompany storms and shifts in weather patterns do affect our bodies, and many people are more sensitive to those effects than others.
Although it's been indicated as a possible cause for everything from changes in blood pressure to an increase in joint pain, it can be difficult to pinpoint barometric pressure changes as the definitive cause for these issues when so many other atmospheric changes — like temperature, precipitation and wind speed and direction — often accompany shifts in weather.
Still, enough people experience symptoms when the barometric pressure changes, so it's worth noting. Here's a look at some of the ways that changes in atmospheric pressure might affect your body:
Headaches: In an interview with The New York Times, Dr. Matthew Fink, neurologist in chief at New York-Presbyterian Hospital/Weill Cornell Medical Center, explained that low barometric pressure can cause headaches or migraines by creating a pressure difference between the atmosphere and the air-filled sinuses. The problem is exacerbated when the sinuses are congested or blocked for any reason.
In a study published in the journal Internal Medicine, researchers asked migraine patients to keep a headache diary for one year. After comparing these diaries with the barometric pressure changes noted at the nearby weather station, they found a direct correlation between lower atmospheric pressure and the onset and duration of migraines. Their report concluded that "barometric pressure change can be one of the exacerbating factors of migraine headaches."
Joint pain: Researchers at Tufts-New England Medical Center in Boston surveyed 200 patients with knee osteoarthritis and found a link between changes in barometric pressure and ambient temperature and changes in knee pain severity. It's not clear why a falling barometer would exacerbate joint pain and arthritis, but studies such as this one confirm that they do. It could be that barometric pressure affects the viscosity of the fluid that lines joint sacs, or it could be that it triggers the pain responses in the nerve endings of the joint. Either way, it's what your grandma has been saying for years: Some people feel pain in their joints when a storm is approaching.
Blood pressure: Just as its name implies, our blood moves through our bodies using a pressure system created by the heart. So it makes sense that this pressure would be affected by the pressure in the air around us. According to biometeorologist Jennifer Vanos, Ph.D., when the barometric pressure drops, so does your blood pressure. For some, this might mean a feeling of dizziness or even blurred vision.
Blood pressure is usually higher in winter when lower temperature cause your blood vessels to become more narrow. That's when more pressure is needed to force blood through those smaller veins and arteries.
"In addition to cold weather, blood pressure may also be affected by a sudden change in weather patterns, such as a weather front or a storm," Sheldon G. Sheps, M.D. writes in MayoClinic. "Your body — and blood vessels — may react to abrupt changes in humidity, atmospheric pressure, cloud cover or wind in much the same way it reacts to cold. These weather-related variations in blood pressure are more common in people age 65 and older."
However, a study in the American Journal of Hypertension found no observed association between blood pressure variability and barometric pressure.
Editor's note: This story has been updated with new information since it was published in October 2016.