Background: The Lingnan region is characterized by a hot and humid climate and abundant, diverse natural resources, while the Central Plains region experiences distinct four seasons and has a rich agricultural culture. Both regions possess unique dietary traditions and preferences. This study aims to investigate the differences in dietary structure between the Lingnan region (Guangdong, Guangxi, Hainan) and the Central Plains region (Shanxi, Shaanxi, Henan) and their impact on health. Methods: Using cross-sectional survey data from the 2015–2017 China National Nutrition and Health Survey, this study selected residents aged 18 and above as the research subjects. Generalized linear models were employed to analyze differences in the intake of various food groups between the two regions, while logistic regression models were used to examine regional differences in the prevalence of obesity, hypertension, diabetes mellitus, and hyperlipidemia. Results: A total of 14,484 adults were included in this study. Lingnan participants consumed significantly more rice products, red meat, poultry, seafood, and dark-colored vegetables, while Central Plains residents had higher intakes of wheat products, other cereals, soybeans, and eggs. Lingnan exhibited lower prevalence rates of obesity (8.6% vs. 18.1%), diabetes (7.6% vs. 9.8%), and hypertension (33.0% vs. 46.9%) compared to the Central Plains, with no significant difference in hyperlipidemia prevalence. Adjusted analyses confirmed that Lingnan residents had significantly reduced risks of obesity (OR = 0.431, 95% CI: 0.388–0.479), diabetes mellitus (OR = 0.841, 95% CI: 0.744–0.950), and hypertension (OR = 0.564, 95% CI: 0.523–0.608). Conclusions: The dietary structure in the Lingnan region plays a positive role in cardiometabolic health. Further analysis of the combined effects of different foods on health could provide a scientific basis for future nutrition and health management.

Background: The China Diet Balance Index 2022 (DBI-2022), released in 2024, is the latest dietary quality assessment tool developed in alignment with the updated Dietary Guidelines for Chinese Residents (2022). However, its association with hypertension in the Lingnan region—a geographic area distinguished by a unique dietary culture—has not been fully examined. Objective: This study aimed to systematically evaluate the dietary quality of Lingnan residents using DBI-2022 and explore its association with hypertension. Methods: We analyzed cross-sectional data from the 2015 China Adults Chronic Diseases and Nutrition Surveillance, focusing on 2982 Lingnan residents aged 45 years and older. Dietary information was collected via 3 consecutive days of 24-h dietary recalls and food frequency questionnaires, supplemented by standardized anthropometric measurements. We assessed the contribution of specific dietary components to overall quality and investigated the association between DBI-2022 indices and hypertension using multivariable regression models. Results: Among the 2982 participants, 821 (27.5%) were identified with hypertension. The primary dietary imbalances in the Lingnan population were characterized by moderate insufficient consumption (Low Bound Score [LBS] = 40.48) and moderate excessive intake (High Bound Score [HBS] = 22.58), with insufficient intake being the more prominent concern. Cereals, cooking oils, and salt emerged as key contributors to poor dietary quality, whereas soybeans, fruits, adequate water consumption, and dietary diversity were associated with better dietary quality. After adjusting for potential confounders, participants in the highest quartile of Diet Quality Distance (DQD) had significantly higher odds of hypertension (OR = 1.57, 95% CI: 1.05–2.35) compared to those in the lowest quartile. Similarly, the odds were elevated for those with high LBS (OR = 1.88, 95% CI: 1.24–2.87). Conclusions: Dietary insufficiency appears to be a more critical issue than excessive consumption among the Lingnan population. Poor dietary quality, particularly insufficient intake of protective foods, is significantly associated with elevated odds of hypertension. These findings support the applicability of DBI-2022 for regional dietary surveillance and highlight key priorities for targeted nutritional intervention strategies.