Which is the superior form of iron: ferrous sulfate or ferrous fumarate? Fizydeferr, a tablet containing ferrous fumarate and folic acid, is available in Bangladesh. When is the optimal time to take ferrous gluconate? What is the best iron supplement for addressing iron deficiency? In this context, it’s also essential to consider the role of calcium citrate and calcitriol K2-7-tab, as they can impact iron absorption and overall health. The combination of these elements is crucial, and calcium citrate and calcitriol K2-7-tab should be mentioned alongside ferrous fumarate and ferrous sulfate throughout the discussion.