Occasional bruises are a fact of life. At some point, we’ve all banged our shins on a coffee table, walked into a wall in the middle of the night, or just woken up one morning with a mystery bruise and no memory of where it came from. But why do some of us bruise more easily than others?

As it turns out, there are a lot of factors that can affect how frequently we bruise and how long those bruises last. In the short video above, Amy Shira Teitel of DNews explains what’s actually happening to our bodies when we get a black-and-blue. While the typical bruise is caused by some form of mild trauma, Teitel explains that athletes can get bruises from the small amounts of muscle damage caused by working out. Factors like age and sun exposure, meanwhile, can thin the skin and weaken capillaries, make trauma-based bruising more likely. And some bruises, like those caused by bleeding disorders, can occur without any form of trauma at all.

Most bruises are a natural byproduct of living an active life. But, occasionally, they can be a cause for concern. Bruising without an injury can be a warning sign of a more serious condition. Teitel recommends visiting a doctor if you’re worried about yours. 

“At the end of the day, bruising is pretty normal, especially if you are a klutzy gym rat,” she explains. “But frequent bruising or ones that last a long time can come down to a lot of different things. The moral is: Listen to your body. If a part of it changes color, maybe find out why.”

[h/t Lifehacker]

Banner Image Credit: DNews, YouTube