Hi, Susan! My non-CAH son has a severe milk allergy, and so gets very little calcium in his diet. The head dietician at Children's Hospital in Winnipeg gave me a chart that shows how much calcium is needed by children according to their age; I can send this to anyone interested. She DID mention that Tums are FINE, and that the expensive supplements out there are not any better. I was also under the impression that it is pretty hard to get too much calcium - I believe it's one of those things that your body takes as much as it needs, and then excretes the rest (? I'm not positive about that one, though!) God's blessings!