UpCal D® Calcium Citrate + Vitamin D3 Powder 20 oz Can, Unflavored, 1026 Cal UpCal D® is a finely grounded powdered calcium that is virtually tasteless. It is 5 times more absorbent than calcium carbonate. UpCal D® yields 500mg of calcium citrate and 500IU of Vitamin D3 per 5 grams of UpCal D®.