I take many supplements along with D3. Are there any supplements that bind D3? My first test was 30, then 40, 40 and last 42. I have been taking 10,000 units daily, along with daily 30 minutes of sun exposure. Nutritiously, I am good (I think), usually consume a couple of tablespoons of coconut oil along with the D3, yet don't seem to be able to raise the blood level. If for some reason, I forget to supplement, then I usually double the next days amount.