Super Cold Temps Can Put Your Heart at Risk—Here’s How to Stay Safe

When it’s freezing out, trekking to the office, getting a run in, or shoveling piles of snow from your walkway can be a major pain. But you’re not wrong to want to lay low when it’s frigid out. Cold weather can do a number on your heart, according to Jeffrey Berger, MD, the director of the Center for the Prevention of Cardiovascular Disease at NYU Langone Health. He explains that, when the body gets cold, blood vessels constrict (a process called vasoconstriction), which causes less blood to pump to various areas of the body—including your heart. Basically, your body is conserving energy to keep you warm, Dr. Berger tells SELF.

When your heart has to work harder to keep things pumping, it can take a toll—especially if you have an underlying cardiovascular condition or a higher risk of developing one. Research suggests that high levels of heart attacks might be tied to lower temperatures, as well as other factors associated with winter months, such as high winds.¹ (Dr. Berger says that’s often linked to people shoveling snow or exercising outside.)

Any temp that’s considered extreme can impact how your cardiovascular system functions. (FYI: What’s considered “extreme” weather can be subjective, but for heat, that usually means two to three consecutive days above 90 degrees and 50% or more humidity. With the cold, it’s near-freezing temps in a warm climate or below zero in a more arctic-like climate). Research published in the journal Circulation analyzing 40 years of data found that exposure to really hot and cold temperatures for extended periods increases the chance of death among people with cardiovascular disease.²

“[Extreme temperatures] change the homeostatic environment of the body,” Dr. Berger explains, which basically means your systems are working overtime to keep your heart, lungs, brain—the whole shebang—stable. Here’s exactly how to keep your heart safe as the colder season creeps in.

How really cold weather can affect your heart

Nidhi Kumar, MD, a cardiologist at Saint Peter’s University Hospital in East Brunswick, New Jersey, tells SELF that people who have a cardiovascular condition—like heart disease, hypertension, or heart failure—should be particularly careful in the cold. That’s because someone with heart failure, for example, already has a difficult time getting their heart to pump blood like it should—and constricting blood vessels only exacerbate the problem. “Any time you already have a condition [that affects the heart], any extra strain forces your already vulnerable [cardiovascular system] to work harder, and it might not be able to take the additional stress,” she says.³