Higher serum iron levels may be associated with a 23.7% lower risk of gallstones, according to a recent cross-sectional study.

In the study, published in BMC Nutrition, investigators examind the association between serum iron levels and the prevalence of gallstones in U.S. adults. They utilized data from the 2017 to 2020 National Health and Nutrition Examination Survey, including 7,847 participants aged 20 years and older. The investigators noted that 845 of the participants were identified as having gallstones.

The study found a statistically significant inverse association between serum iron levels and gallstone prevalence. The participants in the highest tertile of serum iron had a 23.7% lower risk of gallstones compared with those in the lowest tertile (odds ratio [OR] = 0.763, 95% confidence interval [CI] = 0.628–0.929). Additionally, the analysis showed that for each unit increase in serum iron, the likelihood of gallstones decreased by 2.1% (OR = 0.979, 95% CI = 0.965–0.992). These associations remained consistent across subgroups, including gender, age, race, and diabetes status. Although a potential inverse relationship between dietary iron intake and gallstones was observed, this association weakened after adjusting for confounders. Serum ferritin levels were not significantly associated with gallstone prevalence.

The investigators reported that higher serum iron levels were associated with a lower prevalence of gallstones. Further research, particularly prospective studies, is needed to verify the long-term effects of iron metabolism on the development of gallstones.

Full disclosures can be found in the published study.