Vitamin D and rheumatoid arthritis / disease

Here is another pointer to how latitude (similar to multiple sclerosis?) and climate may affect availability of sunlight to the skin, and thus levels of vitamin D ...

http://www.sciencedaily.com/releases/2010/04/100407121227.htm?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+sciencedaily+%28ScienceDaily%3A+Latest+Science+News%29