Will your body absorb a calcium supplement if you take vitamin d with it?

Yes: The short answer is yes. Although not directly as the vitamin d in your supplement (which is either D3 or d3) has to be converted first by your body (in the kidneys) to the active form of vitamin d (called calcitriol). This latter product will in turn aid in the absorption of calcium in the gut.

See below: The body absorbs calcium better with adequate vitamin d administration.

Food BestSource Ca+2: Yes, D3 needed for absorption & often ↓ in US, but best measure vit. D3 concentration; optimal in the 70-80 ng/ml range. Sun tends to trigger conversion of a little cholesterol in skin to Vit D, then converted in liver to D2 & by kidneys & other tissues to D3. D3 impt for Ca absorption, bone & muscle strength + immune function. Best source food & if D3 conc good, unlikely need Ca+2 supplements.