Self-Rated Diet Quality and Cardiometabolic Health Among U.S. Adults, 2011–2018

Introduction: Self-rated health has been extensively studied, but the utility of a similarly structured question to rate diet quality is not well characterized. This study aims to assess the relative validity of self-rated diet quality, compared with that of a validated diet quality measure (Healthy Eating Index-2015) and to examine the associations with cardiometabolic risk factors. Methods: Analyses were conducted in 2020–2021 using cross-sectional data from the National Health and Nutrition Examination Survey, 2011–2018. Nonpregnant adults who responded to the question: How healthy is your overall diet? and provided 2 dietary recalls were eligible (n=16,913). Associations between self-rated diet quality (modeled as a 5-point continuous variable, poor=1 to excellent=5) and Healthy Eating Index-2015 scores and cardiometabolic risk factors were assessed by linear regression, accounting for the complex survey design and adjusting for demographic and lifestyle characteristics. Results: Self-rated diet quality was positively associated with total Healthy Eating Index-2015 scores (p < 0.001) and with all components except with Dairy (p=0.94) and Sodium (p=0.66). Higher self-rated diet quality was associated with lower BMI, waist circumference, glucose, insulin, triglycerides, and HbA1c and with higher high-density lipoprotein cholesterol (all p<0.01). Positive associations with total diet quality persisted across all racial/ethnic groups, although the associations with individual dietary components varied. Higher self-ratings were most consistently associated with better-scored diet quality among individuals with BMI <30 kg/m². Conclusions: Self-rated diet quality was associated with Healthy Eating Index-2015 scores and cardiometabolic disease risk factors. This single-item assessment may be useful in time-limited settings to quickly and easily identify patients in need of dietary counseling to improve cardiometabolic health.