it is not the vitamins dose we need
to take but the serum levels we need
to achieve.the dose must be personalized according
to deficency, this is to achieve the best of possible results
some vitamins like liposoluble can be taken without checking levels like for example vit b complex, vit c, glutathione and vit E
http://www.lef.org/news/LefDailyNews.htm?