Datar Ashlesha
University of Southern California, 635 Downey Way, Los Angeles, CA 90089, United States.
Soc Sci Med. 2017 May;180:143-151. doi: 10.1016/j.socscimed.2017.03.035. Epub 2017 Mar 20.
Childhood obesity remains a top public health concern and understanding its drivers is important for combating this epidemic. Contemporaneous trends in declining family size and increasing childhood obesity in the U.S. suggest that family size may be a potential contributor, but limited evidence exists. Using data from a national sample of children in the U.S. this study examines whether family size, measured by the number of siblings a child has, is associated with child BMI and obesity, and the possible mechanisms at work. The potential endogeneity of family size is addressed by using several complementary approaches including sequentially introducing of a rich set of controls, subgroup analyses, and estimating school fixed-effects and child fixed-effects models. Results suggest that having more siblings is associated with significantly lower BMI and lower likelihood of obesity. Children with siblings have healthier diets and watch less television. Family mealtimes, less eating out, reduced maternal work, and increased adult supervision of children are potential mechanisms through which family size is protective of childhood obesity.
儿童肥胖仍然是首要的公共卫生问题，了解其驱动因素对于抗击这一流行病至关重要。美国同时出现的家庭规模缩小和儿童肥胖增加的趋势表明，家庭规模可能是一个潜在因素，但相关证据有限。本研究利用来自美国全国儿童样本的数据，检验以孩子的兄弟姐妹数量衡量的家庭规模是否与儿童BMI及肥胖相关，以及其中可能起作用的机制。通过使用几种互补方法来解决家庭规模的潜在内生性问题，包括依次引入一系列丰富的控制变量、亚组分析以及估计学校固定效应和儿童固定效应模型。结果表明，有更多兄弟姐妹与显著更低的BMI以及更低的肥胖可能性相关。有兄弟姐妹的孩子饮食更健康，看电视更少。家庭用餐时间、外出就餐减少、母亲工作时间减少以及成人对孩子的监督增加，是家庭规模对儿童肥胖具有保护作用的潜在机制。
