The moderating effect of self-reported dietary adherence on the association between social eating patterns and glycemic control among older adults with diabetes: A gender-stratified analysis using the KNHANES 2022–2024

<title>Abstract</title> <p>Background Social eating is considered beneficial for older adults because it supports social interactions and dietary quality. However, among older adults with diabetes, the impact of social eating on glycemic control may depend on whether individuals actively practice dietary adherence. This study examined whether the association between social eating patterns and HbA1c differs according to self-reported dietary adherence among older adults with diabetes and whether these patterns vary by gender. Methods Data were obtained from the ninth Korea National Health and Nutrition Examination Survey (KNHANES, 2022–2024). A total of 1,015 participants aged 65 years and older with a physician-confirmed diagnosis of diabetes were included. Social eating was categorized into three groups: eating alone, mixed eating, and eating together. The moderating variable was self-reported dietary adherence, and the outcome was HbA1c (%). Survey-weighted hierarchical linear regression analyses were conducted followed by gender stratification analyses. Results In the main-effects model, dietary adherence and social eating patterns were not significantly associated with HbA1c levels. However, after adding the interaction terms, the interaction between dietary adherence and social eating patterns was significantly associated with HbA1c (p &lt; 0.001). The interaction terms for eating alone (p = 0.001) and mixed eating (p = 0.001) were both significant, compared to the eating together group. Gender-stratified analyses showed that the interaction remained significant in both men (p = 0.011) and women (p = 0.038). The estimated mean HbA1c values suggested a crossing pattern; among participants not practicing dietary adherence, HbA1c was higher in the eating alone group (6.84%) than in the eating together group (6.50%), whereas among those practicing dietary adherence, HbA1c was higher in the eating together group (6.85%) than in the eating alone group (6.57%). Conclusions The association between social eating patterns and HbA1c levels among older adults with diabetes varied by dietary adherence. These findings suggest that social eating is neither inherently beneficial nor harmful for diabetes management. Effective dietary interventions should consider dietary adherence, social eating patterns and the broader meal context. Clinical trial number: not applicable.</p>