SAD is major depression that follows the calendar - usually starting in fall as days shorten, deepening through winter, lifting in spring.
NIMH describes the winter-pattern cluster: oversleeping, carb craving, weight gain, heavy fatigue, withdrawal. The line between winter blues and SAD: the blues are common and mild; SAD seriously affects how you feel, think, and function, and recurs with the seasons. It is very treatable - light therapy, psychotherapy, medication, and vitamin D are the four listed categories.
What to do
Common questions
What is seasonal depression and when does it start?
Seasonal affective disorder - SAD - is major depression that follows the calendar. NIMH describes the typical course: mood changes begin and end when the seasons change, most commonly starting in fall as daylight shrinks, deepening through winter, and lifting in spring when longer days return. The symptoms run like depression with a seasonal signature: low mood and lost interest plus a winter-pattern cluster - oversleeping, carb craving, weight gain, heavy-lead fatigue, and social withdrawal (a less common summer-pattern version runs the opposite: insomnia, poor appetite, agitation). The line between winter blues and SAD is the depression line: the "winter blues" are common and mild; SAD is when the change seriously affects how you feel, think, and function - work, relationships, daily life - and it recurs with the seasons, typically for at least two consecutive years. Being far from the equator, female, younger, or having a family history raises the odds. It is very treatable - light therapy, psychotherapy, medication, and vitamin D are the four NIMH-listed categories. In crisis: 988 in the US, or your local crisis line. Pymander, a free AI doctor available 24/7 by text, can help you map your pattern.