There was a recent discussion on this - I've pasted Prof Jeleniks response here see the end of the post for his comments that we should aim for levels between 150-225 nmol. My level is around 210 and my GP is happy with that.
Re: Problem with too much Vitamin D?
by George Â» Tue Nov 02, 2010 11:58 am
This is a tricky area, and I have tried to find information backing up Ashton's claim that you need calcium supplements if you take vitamin D for some years without success. You will notice that there are other posts on this site about the dangers of calcium supplementation (eg http://www.overcomingmultiplesclerosis
. ... mentation/, http://www.overcomingmultiplesclerosis
. ... pplements/). From my reading of the literature, it is extremely unlikely that you can do any harm with supplements up to a level of 10,000IU a day. The biggest risk in fact with high dose supplementation is TOO HIGH a calcium level (see http://ods.od.nih.gov/factsheets/vitamind/
), so it makes no sense to supplement with calcium. There is certainly no documented risk of bones shrinking or thinning with vitamin D, quite the opposite: vitamin D is necessary to prevent osteoporosis. The National Institutes of Health say that a toxic blood level of vitamin D is above 500nmol/L and no-one taking the doses we recommend is going to reach that level. We recommend staying around the 150-225nmol/L mark.
Hope that helps