LAUSR

Objectives The objective is to examine the associations between serum copper, selenium, zinc, and serum estradiol (E2) among 2388 female participants from the National Health and Nutrition Examination Survey (NHANES). Methods To estimate the association between serum copper, selenium, zinc, and serum E2, multivariate logistic regression analyses were conducted. Fitted smoothing curves and generalized additive models were also performed. Results After adjusting for confounding factors, it was found that female serum copper was positively correlated with serum E2. The relationship between serum copper and E2 showed an inverted U-shaped curve (inflection point: 28.57 μmol/L). Serum selenium in women was negatively correlated with serum E2, and in the subgroup of women aged 25-55, the relationship between serum selenium and E2 showed an inverted U-shaped curve (inflection point: 1.39 μmol/L). There was no correlation between serum zinc and serum E2 in women. Conclusions Our study revealed a correlation between serum copper and selenium and serum E2 in women and identified an inflection point for each.