Don't overdo the vitamin D 17. December 2006 William Davis (1) As time passes and I advise more and more people to supplement vitamin D, I gain increasing respect for this powerful "vitamin". I am convinced that vitamin D replacement is the reason for a recent surge in our success rates in dropping CT heart scan scores. I believe it is also explains the larger drops we've been witnessing lately--20-30%. But vitamin D can be overdone, too. Too much of a good thing . . .Despite being labeled a "vitamin", cholecalciferol is actually a hormone. Vitamins are obtained from food and you can thereby develop deficiencies because of poor intake. Deficiency of vitamin C, for instance, arises from a lack of vegetables and fruits. Vitamin D, on the other hand, is nearly absent from food. The only naturally-occuring source is oily fish like salmon and sardines. Milk usually has a little (100 units per 8 oz) because milk producers have been required by law to put it there to reduce the incidence of childhood rickets. A woman came to me with a heart scan score of nearly 3800, the highest score I've every seen in a woman. (Record for a male >8,000!) She was taking vitamin D by prescription from her family doctor but at a dose of 150,000 units per week, or approximately 21,000 units per day. This had gone on for about 3-4 years. This may explain her excessive coronary calcium score. Interestingly, she had virtually no lipoprotein abnormalities identified, which by itself is curious, since most people have some degree of abnormality like small LDL. Obviously, I asked her to stop the vitamin D. Should you be afraid of vitamin D? Of course not. If your neighbor is an alcoholic and has advanced cirrhosis, does that mean you shouldn't have a glass or two of Merlot for health and enjoyment? It's a matter of quantity. Too little vitamin D and you encourage coronary plaque growth. Too much vitamin D and you trigger "pathologic calcification", or the deposition of calcium in inappropriate places and sometimes to extreme degrees, as in this unfortunate woman.Ideally, you should have your doctor check your 25-OH-vitamin D3 blood levels twice a year in summar and in winter. We aim for a level of 50 ng/ml, the level at which the phenemena of deficiency dissipate.