If one is worried about taking vitamin D they might want to consider a high 
quality cod liver oil. We hear about flawed studies all the time that are 
designed to make people fear vitamins and other supplements. Of course, usually 
low quality, synthetic vitamins are used. The studies are designed to fail and 
scare off consumers. Just my 2 cents. I take a liquid supplement that includes 
vitamin D in with calcium, magnesium, zinc and some concentrace minerals. I 
have read where a lack of vitamin D is responsible for people getting the flu 
(lack of sun) in winter. 
Paula