Light therapy before symptoms start

The single most effective strategy I’ve seen is starting bright light therapy in early January, before the late-winter slump hits.

Late winter is tricky because the days are still short but the novelty of winter has worn off, and people tend to drop their prevention habits around the holidays. If you’ve had multiple episodes, you know the pattern: you feel okay through December, then February comes and you’re dragging again.

The key is to front-run it. Most people with SAD start light therapy after symptoms appear, which works but takes weeks to kick in. Starting a few weeks earlier—say, late January—keeps your circadian rhythm stable and heads off the crash. Same goes for dawn simulators and morning walks. You don’t need to overthink it: 30 minutes of 10,000 lux within 30 minutes of waking, every day, no exceptions.

Also worth considering vitamin D supplementation if levels are low, but that’s more of a health baseline than a SAD cure. The real anchor is light timing.

Don’t wait until you’re already in the hole.