Stephen Walsh, Science Coordinator for the International Vegetarian Union, wrote in his article "Beyond Dairy and Calcium: The Truth About Diet and Bone Health," published on the Vegsource website (accessed Apr. 26, 2007):

“Dairy products are not the best source of calcium as they cause calcium losses at the same time as increasing calcium intake. A third of the calcium absorbed from milk and more than two thirds of the calcium absorbed from cheese is wasted this way. In contrast, low oxalate green leafy vegetables such as kale and spring greens provide plenty of well absorbed calcium while at the same time reducing calcium losses. Calcium supplements lie in between in terms of their effect of retained calcium.”

Apr. 26, 2007