Dr. John Faul:

I just have a word of clarity for Deputy Durkan. There is a condition called hypervitaminosis D. People who have this condition have excessively high levels of vitamin D in their blood. This is not caused by eating vitamin D supplements but the processes about which we were talking such as sarcoidosis, some lymphomas and so on. The classic example is sarcoidosis. This is an inflammatory condition where the body creates an enormous amount of vitamin D and it is not regulated by calcium in the blood. Normally, calcium in the blood stops this. It is not regulated, even locally, by vitamin D levels. It is an automatic production of vitamin D by inflammatory tissue. The treatment for it is steroids and anti-inflammatory therapy. Just for clarity, the hypervitaminosis D about which one hears and which can be toxic is not caused by eating supplements but an underlying condition. If the underlying condition is treated, it goes away. We have many patients with sarcoidosis but we give them vitamin D supplements.