Calcium concentration of drinking water to improve calcium intake: A simulation study

The risk of inadequate calcium intake is a worldwide problem. We performed a simulation exercise on the impact, effectiveness, and safety of increasing calcium levels in drinking water using the 2019 Health and Nutrition National Survey of Argentina, which provides water intake and water sources data at the individual level. We simulated the distribution of calcium intake assuming a calcium concentration of 100 mg of calcium per liter of tap water and 400 mg of calcium per liter of bottled water. After the simulation, all population groups had a slightly improved calcium intake. Higher impacts were observed in adults, as reported water intake was higher in adults 19-51 years old. In young adult women, the estimated calcium intake inadequacy decreased from 91.0% to 79.7% when calcium was increased in tap water and to 72.2% when calcium was increased in tap and bottled water. The impact was lower in adolescents and older adults who have higher calcium recommendations and reported lower water intake. Increased calcium concentration of water could improve calcium intake in Argentina, especially in adults as their reported water intake is higher. Combining more than one strategy to improve calcium intake might be required for countries like Argentina with low calcium intake.