So there are some very good websites and interesting articles written by people like you, with support from World Famous Doctors, who have taken the time to educate themselves on this issue. By the way that is the only way they can learn this information......
So check them out.
http://articles.mercola.com/sites/articles/archive/2015/05/10/vitamin-d-recommended-dietary-allowance.aspx?e_cid=20150510Z1_SNL_B_art_1&utm_source=snl&utm_medium=email&utm_content=art1&utm_campaign=20150510Z1_SNL_B&et_cid=DM76062&et_rid=946974057
www.vitamindcouncil.org
Grassrootshealth.net
BB