Vitamin D has to be one of the more unexpected heroes in my arsenal. Every summer I would improve to something approaching normalcy. And every fall I would start to wilt and by Christmas be back into a chronic crash which worsened ... until summer. Happened every year for maybe 8 yrs or something. Started taking Vit. D on the offchance that this summer improvement had to do with sunlight. Seems like it did. I started on D a year and a half ago, in November, so after my yearly decline had begun. Improvement was so gradual I can't say I really noticed it until ... at Christmas time, I wasn't sick. Unheard of. Still wasn't sure it was Vit. D that was making a difference, but I kept taking it every day, more than the traditional medico's recommended dosage. A few months ago I ran out and couldn't afford to get any for awhile. After maybe 2 weeks without it, I began to feel ... heavy. Heavy like gravity had changed. Like I was walking on a planet with far greater gravitational pull, and I could barely keep on my feet. My legs felt like lead and I could hardly lift them. I was panting and gasping for air at the slightest exertion -- something I had not had for over a year. No energy. Head all messed up again. All of this I'd left behind, or thought I had. Remembered I'd stopped taking Vitamin D and a light went on. Scraped together $7 and dragged myself uptown to the drugstore. Like RIGHT then. Didn't wait for anything. Bought my fix. Took some as soon as I got home, handing it out to my sick men here at home as well. (As I always do.) Within 48 hrs, I felt some relief. Within a week it was as if the crash had never happened. I still have symptoms I deal with though they are less, and less frequent, than they used to be. But this all-systems crash has not repeated itself since I started taking Vitamin D again. I am spending time out in the sun every day, but I am still taking my supplement.