I've recently started taking a vitamin D supplement because we only get something like 8 hours of sunlight a day now. I definitely notice that it helps my mood a lot. If I don't take it, I start feeling crabby.

let's not forget that sunbeds produce UVB as well so you can produce vitamin D in these off season months with a few minutes a week in a sunbed. Just remember...don't burn

uuuhhh I don't think time in a sunbed is ever a good idea, even if you don't burn.

I am skeptical of these studies that show evidence for people who are deficient in vitamin D and obesity. People that go outside less tend to exercise outside less as well and are therefore more obese.... there is a third factor at play here.

However, I take vitamin D supplements during the winter because I am hardly ever outside in this weather so I don't get as much sun.

Norway's way ahead of Gwynneth - for ages, many Norwegian children and adults have been consuming cod liver oil in months that have R in the name. Personally, I can't stand the taste, so I usually take it in pill-form rather than oil.