Is vitamin D-3 the same as vitamin D?

When received the results of your vitamin D test, what is the relative importance of the D2 level, the D3 level, and the combined D2 + D3 level?

• I just got my results back, on the result it shows separate amounts for D3 and D2 and above them a total. Although my test result shows as adequate I know that it is actually below optimal from recent reading about D3. My result Total vitamin D: 50.6 nmol/L it says to divide by 2.5 for conversion to ng/mL which converts to 20.24ng/mL which I understand to be deficient. I did my blood test on 1st May, had actually started supplementing on 21st April, started off with just 1000 IU of D3 but have gradually increased it since then, today I upped it to 10,000 IU D3. If I hadn't recently started supplementing D3 before my blood test I realise it would have been an even lower result.

• Answer:

  Vitamin D levels from labs are important and very accurate. Vitamin D is a fat soluble vitamin and you can overdose on it. Symptoms of toxicity isn't prevalent as it increases calcium in your blood and can hasten arterial hardening. It is typical to order just the D2 lab but both labs can help show how your body is getting and utilizing the vitamin. You should follow up with a primary care if prescribed or supplementing with it. If you are in a lower light area especially in winter it would be a good idea to get checked out. And in the summer  to see how your stores are also.