I've been supplementing with D3 since end of 2006 when my sis brought this to my attention, she is challenged with MS....at that time I was feeling a lowness never thinking it was D deficiency. My lab came in at about 16 as I remember....got it up to 80 over a few years time and felt GOOD at 80, then went thru hip replacment in 2010 and that level dropped 40 pts with this surgery. I had read it could happen and sure enough it did. I have been working ever since to maintain 60+ Vit D.

Best to take K2 with D3 as this is the latest research...both are needed.