Literature review of epidemiological studies examining the relationship between calcium and lead levels

Lead has adverse effects on health, society, and the economy. Lead exposure results in increased blood lead levels and storage in bones. Calcium and lead are competitively absorbed and as such calcium can be used to mitigate the body lead burden. Twenty-eight quantitative research studies were reviewed that examined lead exposure (in blood, bone, or breastmilk) and calcium intake or serum calcium to evaluate the efficacy and safety of fortifying potable water supplies with calcium to mitigate lead absorption or resorption. Eighteen of the studies reported a significant inverse relationship between biomarker lead levels and calcium intake or serum calcium. The relationship was most evident with high calcium intake, suggesting a dose-dependent relationship. An intervention with calcium-fortified water could offer an accessible source of supplemental calcium to help meet the recommended dietary allowance (RDA) and mitigate lead absorption. A concentration of 60 mg-Ca/L can supply 22.0 and 16.3% of a 1,000 mg-Ca RDA for men and women, respectively, at the recommended daily water intake.