Neumark-Sztainer Dianne, Wall Melanie, Haines Jess, Story Mary, Eisenberg Marla E
Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis, MN 55454, USA.
J Am Diet Assoc. 2007 Mar;107(3):448-55. doi: 10.1016/j.jada.2006.12.013.
Dieting has been found to predict weight gain in adolescents, but reasons for this association remain unclear. This study aimed to explore potential mechanisms by which dieting predicts weight gain over time in adolescents.
Population-based, 5-year longitudinal study.
Adolescents (n=2,516) from diverse ethnic and socioeconomic backgrounds who completed Project EAT (Eating Among Teens) surveys in 1999 (Time 1) and 2004 (Time 2).
Body mass index (BMI) change over 5 years.
Multiple regressions were used to examine associations between Time 1 dieting and Time 2 binge eating, breakfast consumption, fruit and vegetable intake, and physical activity. Associations were then examined between these behaviors and BMI change. Finally, to test for mediating effects, associations between dieting and BMI change were examined with and without the inclusion of these behaviors, and regression coefficients were compared.
In female adolescents, dieting predicted increased binge eating (P<0.001) and decreased breakfast consumption (P=0.030). In male adolescents, dieting predicted increased binge eating (P<0.001), decreased physical activity (P=0.006), and a trend toward decreased breakfast consumption (P=0.064). These behaviors were also associated with increases in BMI. The association between dieting and BMI increase was weakened, but still remained significant, after binge eating, breakfast consumption, fruit/vegetable intake, and physical activity were included in the model being tested. Thus, the longitudinal association between dieting and BMI increase was partially mediated by these behaviors.
In part, dieting may lead to weight gain via the long-term adoption of behavioral patterns that are counterproductive to weight management.
研究发现节食可预测青少年体重增加，但这种关联的原因尚不清楚。本研究旨在探讨节食随时间推移预测青少年体重增加的潜在机制。
基于人群的5年纵向研究。
1999年（时间1）和2004年（时间2）完成“青少年饮食”（Project EAT）调查的来自不同种族和社会经济背景的青少年（n = 2516）。
5年内体重指数（BMI）的变化。
采用多元回归分析来检验时间1节食与时间2暴饮暴食、早餐摄入、水果和蔬菜摄入量以及身体活动之间的关联。然后检验这些行为与BMI变化之间的关联。最后，为了检验中介效应，在纳入和不纳入这些行为的情况下，检验节食与BMI变化之间的关联，并比较回归系数。
在女性青少年中，节食可预测暴饮暴食增加（P < 0.001）和早餐摄入量减少（P = 0.030）。在男性青少年中，节食可预测暴饮暴食增加（P < 0.001）、身体活动减少（P = 0.006）以及早餐摄入量有减少趋势（P = 0.064）。这些行为也与BMI增加有关。在测试模型中纳入暴饮暴食、早餐摄入、水果/蔬菜摄入量和身体活动后，节食与BMI增加之间的关联减弱，但仍具有显著性。因此，节食与BMI增加之间的纵向关联部分由这些行为介导。
节食可能部分通过长期采用对体重管理适得其反的行为模式导致体重增加。
