Science about age and brains and sleep patterns aside, it's always been my habit to go to bed with the sun, rise with the sun. Even in college, when left to my own devices, it was such a joy to turn everything off at 7pm, in bed and sleeping by 8.
I don't know about the wealth bit, but I'd put what little I have on the health and wisdom pieces of the old adage. There's just something inherently healing about pure dark followed by birdsong.
As for the wisdom, well, I think I've finally decided to stop apologizing for my nature. There must be something in that.