I have some news for you. Are you sitting down for it? Psych! Because the news is: Don’t sit down. Your chair. It’s going to smite you.

This is likely not the first time you’ve heard the warning. On “Rock Center” Thursday, NBC News’ Natalie Morales offers the latest take on the story, blowing the lid off America’s deadly epidemic of sitting down.  “Sitting all day long is literally killing us,” says obesity expert Dr. James Levine, who describes exactly what you’re probably doing right this moment as “dangerous behavior.” And in case you’re thinking none of this applies to you because you Zumba, Morales adds, “A trip to the gym, while beneficial, can’t undo the damage done all day.”