I started taking Vitamin D in December. It was a suggestion from a doc, just because I am easily affected by living in the dark confines of my office.
After a month, it was if someone literally turned a light on. I felt 100% better. I was stunned. I usually thought this extra vitamin stuff was a load of crap.
In my case it worked wonders. Your mileage may vary.
Vitamin D the happy dream pill.
You get 700-800IU from a multivitamin, and then I supplement with a 1000IU gelcap.
I also try to get some D in my diet, maybe in eggs or a little fatty fish.
They say you should keep it under 4000IU.
Any idea of the daily dosage that you're taking that "turned the light on"?