Blue is considered a colour of healing by indigenous people in my part of the world. It kinda fits in with this.
Also, I remember learning years ago, that green is a restful colour. I know that is one way to find peace - lying on the grass, looking up into the sea of green that is a maple tree in summer. ;)
It's kinda surprising that all this is 'new'. The thing about red (and as the main component of orange as one of its complementary colours, perhaps orange as well) can be an agitating colour - that's another thing that I learned as a young'un. Actually, I do love red as well, true red. But once it is tinged with yellow, hmm, it is not as pleasing to my eye. Orange, for me, is dischordant.
very interesting, thanks!