Is it true that having spinach present with calcium prevents absorption of the calcium?
The only time spinach or any other food can hurt the absorption of calcium is when the calcium is not in the amino acid chelated mineral form. The reason other minerals like calcium carbonate or calcium citrate have a hard time when they are combined with foods is because they are not complete and one of the receptor sites of the mineral is bound to chemicals in the food that make it hard to absorb.