Last fall I read that 80 to 90 percent of people are vitamin D deficient. After suffering as I usually do from winter doldrums -- particularly by the time February and March roll around I was researching the idea of getting one of those light boxes to relieve the slumps. Then I read that a large majority of people are vitamin deficient and that the recommended daily amount of Vitamin D was too low. Also, when milk - fortified w/ Vitamin D - was tested they found that the Vitamin D levels were depleted sometimes to more than half the amount. So, this winter, I've added Vitamin D to my daily vitamins and don't you know I have had NO WINTER DOLDRUMS ... in spite of my lowering the temperature of our home to icebox levels (ok, I'm exaggerating). Isn't that exciting?! So, for any of you who live in areas where you hardly expose your skin to the light of day from November to April do some research and consider taking some Vitamin D. I've been taking 800 IU of Vitamin D daily. Some recommend 1000 IU. Anyway, it's worth some research -- I for one can tell you it's made a huge difference in my life this winter! Check it out.