Evaluating the association between dietary zinc intake and cancer risk: Insights from NHANES 2021–2023 with stratified and multivariate analyses.

e22589 Background: Various studies have examined the relationship between dietary zinc (Zn) intake and cancer risk. While some have shown no substantial link, others have proposed an inverse association with colorectal and pancreatic cancers. Given these inconsistencies, we aimed to assess the relationship between dietary Zn intake and cancer diagnosis while adjusting for demographic variables. Methods: A retrospective analysis was conducted using data from the National Health and Nutrition Examination Survey (NHANES) of the U.S. population from 2021 to 2023. Participants' Zn intake and cancer diagnoses were assessed through surveys. Chi-square tests were used to examine the association followed by logistic regression analyses to adjust for potential confounders, including age, gender, and smoking status. A stratified analysis by age groups was conducted to explore potential age-related differences, with a p-value <0.05 being significant. Results: A total of 11,933 respondents' data was analyzed consisting of a majority of females(53.28%). Non-Hispanic whites(52.10%) were the most common ethnicity and 60–79 years(33.75%) represented the most common age group. 61.35% had low Zn intake with the mean ± SD value being 8.12 ± 2.5 mg/day. The chi-square test showed a significant association between Zn intake and cancer diagnosis(χ²=223.5478, p<0.0001). Logistic regression analysis revealed that age was the strongest predictor of cancer diagnosis with individuals aged 60–79 years having significantly higher odds compared to those under 20(OR<0.001, p<0.0001). Zn intake and smoking were not significantly associated, although light smokers showed a marginally protective effect(OR=0.431, 95% CI=0.190–0.979). Stratified analysis showed an inverse association between Zn intake and cancer among the 41-60 age group(p=0.0114). The ROC curve analysis indicated poor predictive ability of Zn intake for cancer diagnosis(c-statistic of 0.520). Conclusions: Unlike previous studies showing a protective effect of Zn intake against various cancers, our findings indicate no overall significance. A notable inverse relationship was observed in the 41–60 age group, suggesting potential age-dependent effects. These findings challenge existing data and the complex relationship between Zn and cancer risk. Further studies are needed to explore the findings.