Ultra-Processed Food Dietary Patterns and Obesity: A Cross-Sectional Analysis of NHANES 2021-2023.

BACKGROUND AND AIMS: Ultra-processed foods (UPFs) are widely consumed and have been linked to obesity. It is unclear whether different UPF dietary patterns vary in their associations with adiposity. This study aimed to identify UPF dietary patterns and examine their associations with adiposity in a nationally representative sample of United States adults. METHODS: In 4003 adults from NHANES 2021-2023, UPF dietary patterns were derived using k-means clustering, and associations of total UPF intake and dietary patterns with BMI and waist circumference were assessed using adjusted survey-weighted linear regression. RESULTS: Each 5% increase in energy intake from UPFs was associated with a 0.25 kg/m2 higher BMI (95% CI: 0.16-0.34) and a 0.60 cm greater waist circumference (95% CI: 0.39-0.81). Three UPF dietary patterns were identified: "Fast Food," "Treats and Diet Soda," and "Lower UPF." Compared with the "Lower UPF" pattern, both "Fast Food" (BMI + 3.20 kg/m2; waist circumference +7.76 cm) and "Treats and Diet Soda" (BMI + 2.83 kg/m2; waist circumference +6.78 cm) patterns were associated with higher adiposity. No significant differences were observed between the two high-UPF patterns. CONCLUSION: Higher UPF consumption was associated with greater adiposity across UPF dietary patterns. These findings from cross-sectional data suggest that overall UPF intake may be an important marker of adiposity, but longitudinal studies are needed to assess temporality and causality.