To investigate the dietary patterns among adults in Guizhou Province over the period from 1991 to 2023 and to offer a scientific foundation for developing strategies related to chronic disease prevention and nutritional enhancement.

The survey data originated from the China Health and Nutrition Survey project, selecting 10 892 subjects with complete data. Dietary data were collected using a 3-day 24-hour dietary recall method. Oblique principal component cluster analysis was employed to screen food groups, while K-means cluster analysis was used to extract distinct dietary patterns. Analysis of variance (ANOVA) was conducted to examine differences in the intake of major foods and nutrients across different dietary patterns. The Cochran-Armitage trend test analyzed changes in the proportion of individuals following different dietary patterns across years. A multivariable logistic regression model examined the interaction between survey year and geographic region. Chi-square tests assessed differences in the proportions of the three dietary patterns among adult residents in Guizhou Province with varying characteristics in 2023.

Dietary patterns among adult residents in Guizhou Province are primarily categorized into three types: high-quality protein, plant-based foods, and mixed. In 2023, the proportion of urban residents following the high-quality protein pattern exceeded that of rural residents, while the proportion adhering to the plant-based foods pattern was lower than in rural areas. As educational attainment increases, the proportion of individuals following the high-quality protein pattern rises, whereas the proportion following the plant-based foods pattern gradually decreases. From 1991 to 2023, plant-based dietary patterns predominated among Guizhou’s adult residents. After 1997, the proportion following plant-based patterns gradually declined while the proportion adopting high-quality protein patterns gradually increased. Starting in 2006, the proportion following high-quality protein patterns rose significantly, while the proportion following plant-based patterns decreased substantially. Multivariate logistic regression analysis revealed a significant interaction between survey year and geographic region for dietary patterns (P<0.000 1). The Northern/Western Guizhou Mixed Development Zone exhibited the fastest increase in the proportion of individuals following the high-quality protein pattern (OR=1.099) and the fastest decrease in the proportion following the plant-based food pattern (OR=0.943).

The proportion of people with more reasonable dietary patterns among adult residents of Guizhou Province increased from 1991 to 2023, but there is still a need to strengthen the publicity of nutritional and healthy diets and to promote the establishment of balanced dietary patterns.