By Hadas Kuznits

PHILADELPHIA (CBS) – A new study from the University of Pennsylvania indicates there’s a correlation between what you eat and how much you sleep.

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Penn Professor Michael Grandner, the lead author of the study, says they studied diet and sleep:

“The main thing we learned from the study was that how much we sleep is associated with what we’re eating. So people who are sleeping longer and shorter amounts have different diets compared to people who are sleeping 7-8 hours.”

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And he says those with the most healthy sleep patterns, generally had better diets:

“So for example, you can look at a highly variable diet indicating a generally more healthy diet because you’re eating more different types of foods.”

But he says it’s unclear if a better diet leads to better sleep — or if better sleep leads to a better diet:

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“So disrupting sleep could lead you to crave more unhealthy foods at more unhealthy times.”