We all have that one friend who is sarcastic and irritable by nature.
But while you might find your friend funny, there are now concerns people with hostile traits such as sarcasm are putting their heart in danger, research suggests.
A study of nearly 2,300 heart attack survivors found those with "hostile traits" such as sarcasm, cynicism, resentment, impatience or irritability were at greater risk of dying of a second heart attack within the next two years.
Researchers also believe the emotional state of always being negative puts a strain on health.
The researchers, from the University of Tennessee, tracked 2,321 heart attack survivors, conducting a personality test that tracked the patients for a 24-month period.