如果你发现衣服正在变得越来越小，或许医生会建议你早点起床，多做些运动。然而根据一项新的研究结果，应该挪动的或许不仅仅只是你的身体。研究人员发现，让人们搬家以远离那些贫穷的邻居，或许能够像药物一样有效地较少你罹患肥胖或糖尿病的可能性。
有关社区能够对我们的健康产生微妙而强大影响的想法至少可以追溯到上世纪20年代，芝加哥大学法学院的社会学家Jens Ludwig这样表示。
以两个低收入的50岁非洲裔美国女性为例：一位生活在伦敦海德公园（周围多是中产阶级的邻居），另一位生活在华盛顿公园（附近多为极端贫穷的社会底层民众）。他说：“我们注意到生活在伦敦海德公园的女性明显要更健康。”但究竟是什么原因造成了这种差异呢？
这也正是美国住房和城市发展部（HUD）想要搞清的问题，由Ludwig率领的一个研究小组对此进行了研究。在一项试图分析教育、职业和社区之间相互关系的研究中，HUD招募了4498位在1994年至1998年居住在公屋中的志愿者，并将他们随机分配到3个小组中。
该项研究为第一组受试者提供租金，从而让他们能够搬到中产阶级社区——只有不足10%的居民收入低于贫困线。第二组受试者则收到了相同的钱，但依然住在原来的社区。作为对照，第三组受试者没有得到一分钱，因此只好留在原地不动。
研究人员在实验的最初阶段检查了每个人的身体健康状况，并在2008年至2010年之间再次进行了体检，测量的数据包括身高、体重，以及血液中与糖分子结合的血红蛋白的数量——这是一项糖尿病指标。
Ludwig的研究团队发现，社区确实是一个重要因素。结果显示，那些受到了资助但没有搬家的人，其健康状况没有大的变化。
然而与对照组相比，那些搬到中产阶级社区的志愿者，其演变为肥胖以及表现出糖尿病症状的可能性减少了5%。研究人员在10月20日出版的《新英格兰医学杂志》上报告了这一研究成果。
Ludwig认为：“这真是一个相当大的影响。”
相关英文论文摘要：
Neighborhoods, Obesity, and Diabetes — A Randomized Social Experiment
BACKGROUND The question of whether neighborhood environment contributes directly to the development of obesity and diabetes remains unresolved. The study reported on here uses data from a social experiment to assess the association of randomly assigned variation in neighborhood conditions with obesity and diabetes.
METHODS From 1994 through 1998, the Department of Housing and Urban Development (HUD) randomly assigned 4498 women with children living in public housing in high-poverty urban census tracts (in which ≥40% of residents had incomes below the federal poverty threshold) to one of three groups: 1788 were assigned to receive housing vouchers, which were redeemable only if they moved to a low-poverty census tract (where <10% of residents were poor), and counseling on moving; 1312 were assigned to receive unrestricted, traditional vouchers, with no special counseling on moving; and 1398 were assigned to a control group that was offered neither of these opportunities. From 2008 through 2010, as part of a long-term follow-up survey, we measured data indicating health outcomes, including height, weight, and level of glycated hemoglobin (HbA1c).
RESULTS As part of our long-term survey, we obtained data on body-mass index (BMI, the weight in kilograms divided by the square of the height in meters) for 84.2% of participants and data on glycated hemoglobin level for 71.3% of participants. Response rates were similar across randomized groups. The prevalences of a BMI of 35 or more, a BMI of 40 or more, and a glycated hemoglobin level of 6.5% or more were lower in the group receiving the low-poverty vouchers than in the control group, with an absolute difference of 4.61 percentage points (95% confidence interval [CI], −8.54 to −0.69), 3.38 percentage points (95% CI, −6.39 to −0.36), and 4.31 percentage points (95% CI, −7.82 to −0.80), respectively. The differences between the group receiving traditional vouchers and the control group were not significant.
CONCLUSIONS The opportunity to move from a neighborhood with a high level of poverty to one with a lower level of poverty was associated with modest but potentially important reductions in the prevalence of extreme obesity and diabetes. The mechanisms underlying these associations remain unclear but warrant further investigation, given their potential to guide the design of community-level interventions intended to improve health. (Funded by HUD and others.)
英文原文链接：https://www.nejm.org/doi/full/10.1056/NEJMsa1103216#Top
