Being a predominantly dairy free household, I often get asked whether my children and I are getting enough calcium. The answer is yes. Despite milk and other dairy products being the most concentrated food source of calcium, foods of vegetable origin, which may not be as concentrated in Calcium are often more bioavailable. For example, there may be 113mg of calcium in 100g of full fat milk but only 32% of this calcium is absorbed, whereas, in kale which has 135 mg of calcium per 100g, 50% of calcium is absorbed. Active absorption of calcium is controlled by Vitamin D.
Foods high in animal protein, caffeine and salt will all increase urinary calcium excretion; just one of many reasons why we should be eating a well balanced varied diet.