Sex Differences in Healthy Eating: Investigating the Moderating Effect of Self-Efficacy.

OBJECTIVES: This study aimed to evaluate sex differences in dietary habits and the moderating effect of self-efficacy on the adoption of a healthy diet. DESIGN: Cross-sectional study. SETTING: The healthy population of Tehran, Iran. PARTICIPANTS: A total of 262 participants from the general population with normal health status. MAIN OUTCOME MEASURE: The adoption of a healthy diet was based on the Healthy Eating Index-2015 (HEI-2015) scores and the moderating effect of self-efficacy on eating behaviors. ANALYSIS: Logistic regression analysis and multiple linear regression (moderation) analysis were conducted using PROCESS macro (version 3.5). RESULTS: The sex-based analysis revealed that females were more likely to adopt a healthy diet vs males (adjusted odds ratio, 1.85; 95% confidence interval, 1.02-3.35). The moderation analysis showed that eating behavior self-efficacy significantly moderated the relationship between sex differences and HEI-2015 scores (ΔR2 = 0.01; P = 0.033). Males with low self-efficacy scores had the highest difference in HEI-2015 with females with low self-efficacy scores, whereas the difference in HEI-2015 was very small in males and females with high self-efficacy scores. CONCLUSIONS AND IMPLICATIONS: Eating behavior self-efficacy had a significantly decreasing moderating effect on sex differences in the adoption of a healthy diet. Future research needs to clarify the impact of eating`` behavior self-efficacy in the adoption of a healthy diet, particularly in males, and to confirm the study's findings.