Variation in vitamin D requirements 7. June 2006 William Davis (0) For Track Your Plaque followers, you know we are very concerned about vitamin D blood levels. My prediction is that, in 10 years, vitamin D will be regarded as an important item on the list of coronary artery disease risk factors. In our experience of trying to stop or reverse heart scan scores, restoration of vitamin D to a blood level of 50 ng/ml appears to have increased our success rate dramatically. As we've talked about before, on the bell curve of vitamin D dosing in a northern climate, the majority of women require 2000 units per day, men require 3000 units per day to achieve a level of 50 ng. However, there are "outliers" on this bell curve, i.e., people who require much more or much less.This week, I saw two people who were very instructive cases of extreme requirements on the high end of vitamin D dosing. Both started with unmeasurable blood levels, i.e., essentially zero ng/ml. On 5000 units of vitamin D per day, both raised their blood levels to around 17-18 ng/ml--in the range of severe deficiency (defined as <20 ng/ml). I advised both to increase their oral dose of vitamin D to 8000 units per day. Notably, both people avoided sunlight and lived in Wisconsin, a terribly sun-deprived locale 10 months a year. Both were also substantially overweight (around 300 lbs each). The vitamin D issue continues to be endlessly fascinating in all its nuances and twists.