We evolved to be outside in daytime. Nerds spend lots of daytime inside. Skin in sunlight makes Vitamin D. In the absence of other information, it'd be surprising if Vitamin D supplements weren't beneficial.
I don't tan either. Sun up here can still give you cancer, and the days are looooooong during the summer.
I've also found that the direct light-on-my-eyeballs has a big difference in waking me up and making me active.