I'm trying to be vegan, and purely natural foods lack sufficient calcium for the Recommended Daily Intake. Links 2 to 4 (but not 1) assert a correlation between calcium supplements and disease.
[1. WebMD :] "Keep in mind that there's really not that much difference between getting calcium in a supplement and calcium in food."
"Calcium-fortified foods -- such as cereals, some juices, and soy milk -- are excellent sources of the mineral, experts tell WebMD."
[2. health.harvard.edu :] An 8-ounce portion of off-the-shelf orange juice contains about 300 mg of calcium. The calcium in fortified soy milk also compares favorably to whole milk. Breakfast cereals (which are also fortified) contain substantial amounts of calcium, especially when combined with low-fat milk. A portion of oatmeal on its own contains just 100 mg of calcium. “But if you cut up some dried figs and add it to a bowl of oatmeal with milk, you easily get about half of what you need without having any supplements,” Dr. Hauser says.
[3. NY Times Blog :] All the researchers agree that, given the widespread use of supplemental calcium, better studies are needed to clarify possible risks and benefits, and to whom they may apply.
Until such information is available, consumers seeking to preserve their bones would be wise to rely primarily on dietary sources of the mineral and to pursue regular weight-bearing or strength-building exercises, or both. Walking, running, weight lifting and working out on resistance machines is unquestionably effective and safe for most adults, if done properly.
[4. NY Times :] The institute’s expert committee, which included bone specialists, concluded that most people don’t need supplements of these critical nutrients and warned of serious health risks from the high doses some now take — including kidney stones and heart disease linked to calcium supplements, and the very falls and fractures that vitamin D is meant to protect against.
5. How and why would the calcium carbonate from calcium supplements be asserted as worse than that in the fortified foods?
6. Isn't solid calcium carbonate (e.g. in supplements) chemically the same as aqueous calcium carbonate (e.g. in fortified drinks)?
7. Are calcium supplements really worse than fortified foods with calcium?