When the weather cools, many of us idly dream of becoming bears and hibernating in a warm burrow until spring comes again. While the cozy season won't exactly force you into a months-long snooze, cold weather can affect your sleep in ways you might not expect. Sleep patterns are affected by many different factors in the body and the environment, and as days get shorter and wind begins to howl, our rest can be affected in unusual ways.
Sleep science is an emerging area of research, and scientists are still understanding the many different ways in which weather, humidity, and temperature can affect how you sleep. The tie between winter and shifting sleep has been interesting observers for hundreds of years. Medieval doctors noted that sleep seemed to "cool" bodies, though they tied it to their belief that health was controlled by hot and cold "humours" like phlegm and bile, and thought that excess sleep caused cold humours to increase. These days, researchers know a lot more about the ways in which the sleeping body is affected by the world, and it's not anything to do with phlegm (though colds can affect your sleep if you're woken up by your own sneezing). Here are a few unusual ways your sleep may change as the days (and nights) get colder.