[ypolito]

From wikipedia:

> Seasonal affective disorder is a mood disorder subset in which people who have normal mental health throughout most of the year exhibit depressive symptoms at the same time each year, most commonly in the winter.

I usually get depressed in the summer though, even when I get enough unfiltered sunlight.

[JimboOmega]

There are all kind of things that happen seasonally that might dampen your mood (for instance people taking vacations, students being home from school, work being more/less busy, outdoor exercise options changing, etc). Your depression might not have anything to do with that and just be a random variation that happened to occur in the summer.

Most depression has nothing to do with SAD; it's merely a specific type. It's a type that has a fairly straightforward treatment, thankfully!

I often have a depressed mood in November and December when the sun is at its lowest, but my family also likes to make "the holidays" as miserable an experience as possible, so it's really no surprise and probably unrelated to light levels.

[majewsky]

FWIW, I have the same symptoms in winter, but none of the reasons you list apply to me. I can easily see SAD being caused by lack of natural light, and I try to spend as much time as possible in sunlight (which is hard given a normal work schedule).

[eurg]

"most commonly", but there is some evidence that SAD is not triggered only by amount of light:

"This model also explains the otherwise confusing tendency of some SAD sufferers to get depressed in the summer. The problem isn’t amount of light, it’s circadian rhythm disruption – which summer can do just as well as winter can."

https://slatestarcodex.com/2018/07/10/melatonin-much-more-th...