Sleep deprivation is tied to a whole bunch of health problems, such as increased anxiety, bad bones and overeating. And, according to a new study, it also messes up your relationships.

Researchers at the University of California-Berkeley found that sleep deprivation effects your expressions of gratitude.

So, instead of your mate feeling appreciated, your lack of sleep is causing him or her to have feelings of being taken for granted.

This happens because poor sleep makes us more selfish – and we end up prioritizing our own needs over our partner's