I'm not sure about suicide but for about a year back in high school I used to wear round sunglasses with blue tinted lenses all the time. I always told people that when I was wearing them I always felt more mellow (and no, it wasn't because of the smoke, didn't venture into that area until well after high school) I guess it wasn't just in my head

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interesting clip. My brother used to work in a high security psychiatric ward and was often required to escort agitated 'clients' to a 'blue' room to help mellow them out.