Researchers have been studying night workers for years, trying to better understand what happens to our circadian rhythms and our bodies when we are up-and-at-it at the time we’re supposed to be asleep, reports STAT.

 The findings do show a physiological disconnect — many of the genes associated with circadian cycles kept their rhythms, but seemed to fire at lower strength. Many genes couldn’t (or maybe wouldn’t?) adapt their expression to a flip-flopped sleep schedule. Gene expression related to metabolism, and the function of certain immune cells and potential cancer-causing signaling pathways were also altered.