Li Yi, Guo Guang
Department of Sociology, University of Macau, Macau, China.
Department of Sociology, University of North Carolina at Chapel Hill, USA; Carolina Population Center, University of North Carolina at Chapel Hill, USA; Carolina Center for Genome Sciences, University of North Carolina at Chapel Hill, USA.
Soc Sci Res. 2021 Jan;93:102483. doi: 10.1016/j.ssresearch.2020.102483. Epub 2020 Oct 20.
The role of peers in explaining the obesity epidemic is difficult to evaluate, largely due to selection (the tendency of similar individuals to make friends with each other). Our study addresses this selection issue by using data from a natural experiment of randomly assigned college roommates. We investigate whether and how peers, gender, and the FTO gene interactively influenced BMI. We find that women with a weight-prone version of the gene were about three pounds lighter if assigned frequently-exercising roommates than if assigned non-frequently-exercising roommates. However, living with frequently-exercising roommates had little impact for women without the weight-prone version of the gene or for men regardless of genotype. We find that individuals with the weight-prone version of the gene exercised more often when assigned frequently-exercising roommates. This might be a mechanism through which the effect of frequently-exercising roommates worked.
同伴在解释肥胖流行现象中所起的作用很难评估，这主要是由于选择性因素（即相似的个体倾向于相互结交为朋友）。我们的研究通过使用来自一项随机分配大学室友的自然实验的数据来解决这一选择性问题。我们调查了同伴、性别和FTO基因是否以及如何交互影响体重指数（BMI）。我们发现，携带易胖型基因的女性若被分配到经常锻炼的室友，其体重比被分配到不经常锻炼的室友时轻约三磅。然而，对于没有易胖型基因的女性或无论基因型如何的男性而言，与经常锻炼的室友同住对他们的体重影响不大。我们发现，携带易胖型基因的个体在被分配到经常锻炼的室友时会更频繁地锻炼。这可能是经常锻炼的室友产生影响的一种机制。
