Weight Control and Weight Change Among Adolescent

描述（由申请人提供）：本提案旨在评估国家青少年健康纵向研究（Add Health）中青少年和成年早期体重增加和超重和肥胖发展的行为预测因素。在横断面研究中，研究人员观察到节食和超重或肥胖之间有很强的联系。节食和体重状况之间的横断面关联可能是由于超重的人比正常体重的同龄人更有可能通过节食来减肥。由于大多数节食努力都没有成功，或者至少没有成功地维持下去，超重的人可能会保持超重，而不是因为他们的节食尝试。只有前瞻性分析才能帮助确定节食是否会导致体重大幅增加，还是仅仅是一种无效的减肥和保持体重的策略。Add Health是一项以学校为基础的研究，研究对象是来自美国80所高中和52所中学的青少年。该样本在国家地区、城市/城市、学校类型、种族和学校规模方面代表了美国学校。我们试图分析第一波（1995-1996）、第二波（1996）和第三波（2001-2002）的数据，以评估1995年至2001年之间的体重变化是否可以通过体重变化目标（例如，减肥、保持体重或增加体重的愿望）或1995年至1996年的体重控制实践来预测。具体来说，我们将评估是否通过节食、使用减肥药、自我诱导呕吐和/或使用泻药来预测超重和肥胖的发展。此外，我们将调查报告使用运动来保持体重的青少年是否会比不使用运动作为体重控制行为的同龄人增加更少的体重。我们还将调查那些报告说他们正在试图增加体重的青少年的体重变化模式。我们将评估自我报告使用节食、运动或举重来增加体重或增加肌肉是否能预测六年内体重的变化。我们将评估这些关联是否存在，以及它们是否因性别和/或种族/民族而异。这项研究将有很好的能力来检测中度关联（例如，相对风险>= 1.6）。Add Health是唯一一项针对青少年的大型前瞻性研究，有足够的男性和非白人受试者来评估预测因子是否因性别和/或种族/民族而变化或被修改，因此我们的结果应该对该领域做出重要贡献。

DESCRIPTION (provided by applicant): This proposal is to assess the behavioral predictors of weight gain and the development of overweight and obesity in adolescence and early adulthood in the National Longitudinal Study of Adolescent Health (Add Health). In cross-sectional studies researchers have observed a strong association between dieting and being overweight or obese. The cross-sectional association between dieting and weight status may be due to overweight individuals being more likely than their normal weight peers to go on diets to lose weight. Since most dieting efforts are not successful, or at least not successfully maintained, overweight individuals may remain overweight despite, not because of, their dieting attempts. Only prospective analyses can help to determine whether dieting leads to great weight gain or is simply an ineffective strategy to lose and maintain weight. Add Health is a school-based study of adolescents from 80 high schools and 52 middle schools from the U.S. This sample is representative of U.S. schools with respect to region of country, urban/city, school type, ethnicity, and school size. We seek to analyze data from Wave I (1995-1996), Wave II (1996), and Wave III (2001-2002) to assess whether weight change between 1995 and 2001 is predicted by weight change goals (e.g., desire to lose, maintain, or gain weight) or weight control practices in 1995 and 1996. Specifically we will assess whether the development of overweight and obesity is predicted by dieting, using diet pills, self-inducing vomiting, and/or using laxatives to lose weight. In addition, we will investigate whether adolescents who report using exercise to maintain their weight will gain less weight than their peers not using exercise as a weight control behavior. We will also investigate the weight change patterns of adolescents who report that they are trying to gain weight. We will assess whether self-reported use of dieting, exercise, or weight lifting to gain weight or build muscle predicts weight change over a six-year period. We will assess whether these associations exist and whether they vary by gender and/or race/ethnic group. This study will have good power to detect moderate associations (e.g., relative risk >= 1.6). Add Health is the only large prospective study of adolescents with enough males and non-white subjects to assess whether predictors vary by or are modified by gender and/or race/ethnicity, therefore our results should make an important contribution to the field.