[strontian]

Hm, not sure how effective it would be in ‘worse’ climates. I’ve found it to be helpful on grey days as well.

I also use a Lumenator (https://www.lesswrong.com/posts/hC2NFsuf5anuGadFm/how-to-bui...) which I think of as icing on the cake. Perhaps ‘cure’ is too strong a word, but it’s been the most effective thing other than leaving the hemisphere for someplace sunnier which was my previous approach.