Prospective effects of dietary intake on lung function of pupils in Chengdu City / 中国学校卫生

Objective@#To investigate the prospective effects of intake of each food group on the development of lung function of pupils,so as to provide theoretical basis for promoting the healthy development of lung function and preventing chronic respiratory diseases in Chinese children.@*Methods@#A cluster stratified sampling method was used to select a total of 893 pupils in grades 2-5 from Chengdu in November 2021. Dietary data of respondents were collected using a food frequency questionnaire within the past year,then the food group intake was categorized into T1, T2 and T3 from low to high by the trichotomous method, and anthropometric measurements including lung capacity were obtained in 2022. Logistic regression models and test for trend were used to analyze the prospective effects of intake of each food group on lung function development of pupils.@*Results@#Among male students, consumption of vegetables [118.6(50.5, 188.2)g/d] and milk and dairy products [200.0(73.3, 250.0)g/d] were higher in the excellent lung capacity group than in the non excellent lung capacity group [90.0(37.1, 192.9), and 178.6(35.7, 250.0)g/d],with statistically significant differences ( Z =-1.98, -2.24); among girls, the group with excellent lung capacity consumed less staple food [391.1(273.6, 511.4)g/d] than the group with non excellent lung capacity [407.4(309.5, 594.3)g/d], and the group with excellent lung capacity consumed more aquatic products [31.2(14.6, 69.8)g/d] and milk and dairy products [215.0(107.1, 250.1) g/d ] than that of the non excellent lung capacity [19.4(10.7, 58.3), 114.3(35.7, 250.0)g/d] ( Z =-2.01, -3.33, -5.10)( P < 0.05 ). After adjusting for energy, body mass index Z score(BMI Z ), mother s education level, averge family income monthly, whether presence of smokers in the living environment, and whether participation in physical activities during the past week, among male students, T3 group of vegetable intake ( OR =0.48, 95% CI = 0.27-0.86), T2 group of bean and soy product intake ( OR = 0.52 , 95% CI =0.27-0.96)，T2 and T3 groups of milk and dairy products intake (T2： OR =0.54, 95% CI =0.31-0.93; T3： OR = 0.52 , 95% CI =0.30-0.90) were negatively associated with non excellent lung capacity ( P <0.05). Among girls, T3 group of aquatic product intake( OR =0.52, 95% CI =0.28-0.97), T2 and T3 groups of milk and dairy product (T2: OR =0.44, 95% CI =0.25- 0.76 ;T3: OR =0.33, 95% CI =0.19-0.59) were negatively associated with nonexcellent lung capacity, whereas the T2 group of red meat intake ( OR =2.51, 95% CI =1.37-4.67) was positively associated with non excellent lung capacity. Non excellent lung capacity was found to be negatively associated with vegetable and milk and dairy product intake in boys by test for trend; in girls, milk and dairy products intake was negatively associated with non excellent lung capacity, whereas red meat intake was positively associated with non excellent lung capacity ( t =-1.13，-0.44；-3.03，1.95, P trend <0.05).@*Conclusions@#Milk and dariy products intakes reduce the risk of non excellent lung capacity in pupils, vegetables intakes reduce the risk of non excellent lung capacity in boys, and the intake of red meat increases the risk of non excellent lung capacity in girls. Promoting rational food choices is necessary for children to improve healthy lung development.