Blood clots may not be the most pleasant topic to dwell on, but here’s the hard truth: they’re a quiet danger that affects hundreds of thousands of people each year, often with little to no warning. While they aren’t always fatal, ignoring them can lead to severe and lasting health problems. That’s why when cardiologists raise a serious alarm and say, “Stop doing this immediately,” it’s wise to pay attention.

So what’s the habit they’re talking about?

Sitting for extended periods of time.
Yes—something as ordinary as spending hours on the couch, staying glued to your laptop, or remaining seated throughout a long flight without moving can significantly increase the risk of dangerous blood clots.

Let’s take a closer look at what’s happening inside your body—and how you can keep your circulation healthy.

What Are Blood Clots, Really?
Think of blood clots as your body’s built-in repair system. When you scrape your knee or cut a finger, platelets rush in and clump together to stop the bleeding. That process creates a clot—and in those situations, it’s essential.

Trouble begins when clots form inside blood vessels without a clear reason. Picture traffic on a busy highway suddenly coming to a complete stop for no apparent cause—that’s similar to what happens when a clot disrupts the normal flow of blood through your veins or arteries. If a clot breaks loose and travels, it can become lodged in the lungs (causing a pulmonary embolism), the brain (leading to a stroke), or the heart (triggering a heart attack), resulting in potentially life-threatening consequences.