Seasonal affective disorder, or SAD, is a type of depression that around 4 to 6 percent of Americans develop in the winter each year. SAD typically sets on during the changing of the seasons, when the sun begins to set earlier, meaning people get far less of that essential vitamin D. Many people, unfortunately, don’t take SAD as seriously as other forms of depression because they just think, “This will go away in the spring or summer.” But that is still several months spent feeling very depressed and unlike yourself. And just like any other form of depression, SAD can make it very difficult for a person to carry out their daily tasks, and do things that are important for their health, like exercise and socialize. Ironically, one of the reasons SAD sets on in the winter–especially in places with severe winters–is because the weather makes it harder for people to socialize. Nobody wants to tough out the icy streets and windy roads, so they stay indoors. But, like we said, you don’t need to live with SAD. Here is how to beat seasonal affective disorder this fall and winter.