Ultra-Processed Food Consumption Is Associated with an Increased Risk of Abdominal Obesity in Adults: A Cross-Sectional Study in Shanghai

Ultra-processed foods (UPFs) have become increasingly prevalent in modern diets due to their convenience and variety. These foods typically have higher energy density and lower nutrient density, contributing to adverse health outcomes such as obesity and hypertension. This study aimed to explore UPFs consumption status and its association with health outcomes in a representative Shanghai population, using data from the Shanghai Diet and Health Surveillance. Multi-stage stratified random sampling was adopted, with dietary intake assessed via 3-day consecutive 24 h dietary recalls, and health outcomes evaluated through physical measurements and biochemical indicators. UPFs account for 11.2% of total energy intake overall and 29.0% among high consumers. The overall prevalence of abdominal obesity was 58.9%. After adjusting for confounders, high UPFs consumption was associated with a 28.5% higher risk of abdominal obesity versus non/low consumption (OR = 1.285, 95% CI: 1.059–1.559, p = 0.011), with no significant associations with hypertension or diabetes. High UPF consumption is an independent risk factor for abdominal obesity in Shanghai residents, highlighting its public health relevance.