A growing body of research links traffic-related environmental factors to childhood obesity; however, the evidence is still inconclusive. This review aims to fill this important research gap by systematically reviewing existing research on the relationship between traffic-related environmental factors and childhood obesity. Based on the inclusion criteria, 39 studies are selected with environmental factors of interest, including traffic flow, traffic pollution, traffic noise, and traffic safety. Weight-related behaviours include active travel/transport, physical activity (PA), and intake of a high trans-fat diet or stress symptoms; weight-related outcomes are mainly body mass index (BMI) or BMI z-scores and overweight/obesity. Of 16 studies of weight-related behaviours, significant associations are reported in 11 out of 12 studies on traffic flow (two positively and nine negatively associated with PA), five out of six studies on traffic safety (four positively and one negatively associated with PA), one study on traffic pollution (positively with unhealthy food consumption), and one study on traffic noise (negatively associated with PA). Among 23 studies of weight-related outcomes, significant associations are reported in six out of 14 studies on traffic flow (five positively and one negatively associated with obesity outcome), seven out of 10 studies on traffic pollution (all positively associated with obesity outcome), and two out of five on traffic noise (all positively associated with obesity outcome). Our findings show that long-term traffic pollution is weakly positively associated with children's BMI growth, and traffic flow, pollution, and noise could affect weight-related behaviours. Associations between traffic density and noise and weight status are rather inconclusive.

中文翻译：

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交通相关环境因素和儿童肥胖：系统回顾和荟萃分析。

越来越多的研究将与交通相关的环境因素与儿童肥胖联系起来；然而，证据仍然没有定论。本综述旨在通过系统回顾有关交通相关环境因素与儿童肥胖之间关系的现有研究来填补这一重要的研究空白。根据纳入标准，选择了 39 项研究，其中包括交通流量、交通污染、交通噪声和交通安全等环境因素。与体重相关的行为包括积极的旅行/运输、身体活动 (PA) 以及摄入高反式脂肪饮食或压力症状；与体重相关的结果主要是体重指数 (BMI) 或 BMI z 分数和超重/肥胖。在 16 项与体重相关的行为研究中，12 项交通流量研究中有 11 项报告了显着关联（两项与 PA 呈正相关，九项与 PA 呈负相关），六项交通安全研究中有五项（四项与 PA 呈正相关，一项与 PA 呈负相关），一项关于交通污染的研究（与 PA 呈正相关与不健康的食物消费），以及一项关于交通噪音的研究（与 PA 呈负相关）。在 23 项体重相关结果研究中，14 项关于交通流量的研究中有 6 项报告了显着关联（5 项与肥胖结果呈正相关，1 项与肥胖结果呈负相关），10 项关于交通污染的研究中有 7 项（均与肥胖结果呈正相关） ，以及五分之二的交通噪音（都与肥胖结果呈正相关）。我们的研究结果表明，长期交通污染与儿童的健康呈弱正相关 s BMI 增长、交通流量、污染和噪音可能会影响与体重相关的行为。交通密度与噪音和重量状态之间的关联尚无定论。