Hi, Tina. Think of SAD as winter depression, brought on by lack of exposure to the amount of sunlight we're used to. People in higher latitudes get hit harder than those in more temperate climates. Ironically, scorching hot summers that drive people indoors into dark rooms may also cause SAD. Our indoor lifestyles can also set us up for SAD, so getting outdoors is critically important, even on cloudy days. A light box is also an option.

People with bipolar are sitting ducks for SAD. If we think of bipolar as a cycling illness that throw our circadian rythms off, as well as our moods, well - seasons are the mother of all cycles. This isn't just me speculating. This analysis appears in the definitive bipolar text by Goodwin and Jamison.

Hope this helps -