Are you being lazy, or do you really need more sleep as the temperature lowers and the amount of daylight decreases? “I don’t think we need more sleep as the days get shorter, but people will often feel sleepier,” says Dr. Karin Johnson, a sleep medicine specialist and spokesperson for the American Academy of Sleep Medicine (AASM), a global network of sleep medicine specialists that advances sleep health worldwide. Reasons we feel more lethargic in winter and fallOverall, we naturally tend to sleep more in winter and as the weather generally gets colder into fall. This disconnects us from nature’s rhythms and can shift our natural sleep patterns. Seasonal Affective Disorder (SAD)About five percent of adults in the U.S. experience Seasonal Affective Disorder (SAD), symptoms of depression that occur during the winter months.