Revisiting the Healthy Immigrant Effect: Nativity and Oral Health Disparities Among U.S. Adults in NHANES 2017–2018

Background The "healthy immigrant effect" posits that foreign-born individuals often arrive in host countries with health profiles superior to those of native-born populations. However, the durability of this advantage in oral health remains poorly understood. This study investigates oral health disparities by nativity and duration of U.S. residence using nationally representative data. Methods We analyzed cross-sectional data from 5,856 adults (aged ≥ 18) in the 2017–2018 National Health and Nutrition Examination Survey (NHANES). Self-rated oral health and recency of dental visits were examined across nativity groups (U.S.-born vs. foreign-born) and by length of U.S. residency (< 10 vs. ≥10 years). Descriptive statistics, cross-tabulations, and chi-square tests were conducted with appropriate sample weights. Results Foreign-born individuals represented 30.5% of the sample. Compared to U.S.-born adults, a greater proportion of immigrants reported not having visited a dentist in over a year and rated their oral health as "fair" or "poor" (p < 0.001). Among foreign-born respondents, those who had lived in the U.S. for ≥ 10 years were significantly more likely to have had a dental visit within the past year and reported better self-rated oral health than those with < 10 years of residency. Conclusion Findings indicate that oral health advantages among immigrants diminish with time and are linked to reduced access and delayed utilization of dental care. Policy efforts should prioritize early integration of immigrants into preventive oral health systems to reduce long-term disparities.