I am an advocate of not exposing the eyes to excessive "light" no matter what the source. Few times in my life have I ever had "eyeache" worse than a day at the beach sans dark glasses (I don't ski).
Be it diet, vitamins, supplements or anything else, the tendency seems to be "way more is way better".
Shining a light directly onto the eye IMHO is foolish. Why not try to mimic sunlight times a conservative 130% in a room and then trade intensity for time? There is no question in my case (the only case that matters to me), that being conservative but direct works to put me into a more cheerful mood. Lights, and music -- maestro. Hah! A dose of strong sunlight and a set by the Beach Boys takes me back to my family, and shirt sleeve weather. Until I get cut again for my degenerating spine, I will be away from home -- and I damned do not like it.
My aged body reacts to stimuli and lack of, a heck of a lot differently than what it did fifteen or thirty years ago. I am way more sensitive to cold. Gray, and gloomy makes me gloomy. So, the best way to change this is to change the environment. Some people choose drugs. To me that is like ignoring the rumble and jerking of running on a flat tire by turning up the radio.
Whatever it takes. I'm sure some entrepreneur has a thousand dollar solution for a fifty dollar problem. Speaking of which, I have the work area lighting to complete.
