Recently I was asked about the safety of calcium fortified foods. The person who asked the question was concerned because their physician had advised her to stop taking calcium supplements, and they were now unsure whether they should have foods that were fortified with calcium.
The short answer is, yes, according to the Institute of Medicine (IOM) the Food and Drug Administration, and a number of other sources, calcium fortified products are safe.
Now the long version:
Firstly, I want to say that if your doctor advises you to do (or not do) something, you should probably listen, and/or seek a second opinion from another physician. Without having access to a person’s medical records, and without being in the exam room for the conversation, I would be exceedingly presumptuous to comment on a doctor’s guidance related to a specific patient.
I do want to venture a guess at why the physician gave this advice, as I think it may shed some light on the question of safety. Speaking generally, some studies have shown an increased risk of heart disease related to calcium supplementation for adult women. However a recent study by the Brigham and Women’s hospital with more than 74,000 participants followed for 24 years, showed no increase in risk for heart disease for women using supplemental calcium.
That’s a huge amount of people followed for a long time by a very well-regarded institution, so I’m inclined to trust the results. The flip side is that calcium supplementation has not been shown to be particularly effective for reducing rates of osteoporosis in post-menopausal women. So if some studies suggest risk of heart disease, and most studies show no benefit for adults, why continue to supplement? I’m guessing that this may have been the basis of the doctor’s advice: Some indication of risk + no indication of benefit = why bother? Especially in terms of supplements, I agree with this approach. Taking dietary supplements should be done with a specific goal.
Back to the question at hand: Is supplemental/fortified calcium safe for children? The Institutes of Medicine (IOM) sets the Tolerable Upper Limit (“A Tolerable Upper Intake Level (UL) is the highest level of daily nutrient intake that is likely to pose no risk of adverse health effects to almost all individuals in the general population”) for calcium at 2500mg for 1 – 8 year olds and 3000mg for 9-18 year olds. They don’t make any differentiation between sources (i.e. whole food, fortified food, supplements) in setting this limit.
The Office of Dietary Supplements (ODS), of the Department of Health and Human Services has a great page on Calcium. You can also find the Recommended Daily Allowances for different age groups there. You’ll notice that calcium recommendations are higher during the adolescent and teenage years. As children are growing into adults, they are making a lot of bone that will need to last them for the rest of their life, so this time is critical for calcium intake. Milk is a significant source of calcium, so for children with milk allergies or lactose intolerance, finding an alternative source for calcium is important. Other calcium-rich foods are the first option for filling the gap, followed by fortified foods, and then supplements.
As noted on the ODS Calcium page linked to above, it’s unlikely that you’ll get excessive calcium from food. Non-dairy milks and yogurts are often fortified to match the calcium content of the products they are similar to, so it seems unlikely that you would end up providing excessive calcium from those source. That said, take care with adding to many calcium fortified foods to a diet.
Lastly, I think this page from Berkeley Wellness provides good information as well: