Dietary, physical exercises and mental stress in a Chinese population: a cross-sectional study

BACKGROUND: Mental health is affected by both genetic and environmental factors. However, previous studies have showed conflict findings about the role of lifestyle and little is known about the situation of the Chinese population. The purpose of this study was to explore the relationship between the frequency of food consumption, physical exercise condition and mental health, as well as factors related to mental stress in Chinese. METHODS: We recruited 8160 residents who had health examinations in a public hospital during June 2016 to May 2018. Demographic characteristics, the frequency of food consumption, physical exercise condition and mental health status was collected by a questionnaire. We estimated the association using the odds ratio (OR) and 95% confidence interval (CI) based on Binary or ordinal logistic regression models. A classification and regression tree (CART) demonstrated the prediction of the value of a target variable based on other values. RESULTS: The logistic regression model and classification tree model both found that the frequency of fresh vegetables or fruit and fried foods consumption and the current state of drinking alcohol were related to mental stress. The degree of mental stress reduced significantly with increasing consumption of fish (OR = 0.80, 95% CI: 0.71–0.90) and regular exercise (OR = 0.55, 95% CI:0.48–0.64) in females and increased consumption of fish (OR = 0.55, 95% CI: 0.48–0.64) and cereal crop (OR = 0.77, 95% CI: 0.68–0.89), fish (OR = 0.87, 95%CI:0.77–0.96) and regular exercise (OR = 0.61, 95%CI:0.53–0.70) in males. On the contrary, the frequency of consumption of desserts (OR = 1.43, 95% CI: 1.26–1.62) and the current of drinking alcohol (OR = 1.47, 95%CI:1.21–1.79) in females and meat (OR = 1.47, 95%CI: 1.31–1.65), pickled and smoked food (OR = 1.18, 95%CI:1.05–1.32) and the current state of drinking alcohol (OR = 1.25, 95%CI:1.12–1.40) in males were related to an increased risk of mental health. CONCLUSIONS: Our study showed that both the frequency of some food consumption and physical exercise condition were associated with mental health and affected the degree of stress, which provided novel insights into interventions. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12889-021-11189-7.