Physical Activity and Diet in the Prevention of Obesity in Men and Women

描述（由申请人提供）：美国日益增长的肥胖流行病提高了所有年龄段初级预防的重要性；然而，预防工作通常侧重于儿科环境中的社区干预研究或已经超重或肥胖的成年人的临床干预研究。肥胖通常发生在成年期，因此有必要提高对预防成年期肥胖的长期策略的理解。流行病学文献对除总体力活动外的特定类型或强度的体力活动以及可能与肥胖发展和成年中后期长期体重增加有关的饮食模式的研究有限。因此，本修订提案响应PA-06-256（肥胖症探索性/发展性临床研究资助），并寻求在现有的两项大型男性和女性前瞻性队列研究中，将偶发性肥胖症作为一个新的终点。哈佛校友健康研究包括12805名年龄在55岁之间的男性，他们在1988年完成了一份基线问卷，并进行了10年的随访。女性健康研究包括39876名年龄在45岁之间的女性，他们在1992年获得了基线信息，并进行了超过12年的肥胖发展和长期体重增加的随访。在这项建议中，我们将仔细评估身体活动、身体不活动和饮食在预防成人发病肥胖和最初非肥胖男性和女性长期体重增加中的作用。我们的第一个主要目的是在长期随访中检查缺乏运动是否与肥胖或体重增加的风险增加有关。我们还将检查身体活动的类型（如步行和其他常见的运动形式）、频率和强度（如中度、剧烈）。其次，我们将确定特定的饮食因素（例如西方与谨慎的饮食模式、水果和蔬菜、纤维、碳水化合物、乳制品和酒精）是否与肥胖风险增加或体重增加有关。最后，我们将确定上述关联是否因存在或不存在中间临床因素（如高血压、糖尿病、高胆固醇血症或父母肥胖史（仅适用于男性））而改变。我们有很好的能力来评估我们的假设，得出关于不同类型和强度的身体活动、久坐行为和饮食因素在肥胖一级预防中的作用的临床有意义的结论。随着这些队列中成人发病肥胖和长期体重增加的成功发展，我们希望这一提议能带来更大的R01拨款，以更大的范围来研究身体活动、身体不活动、饮食和相关生物标志物和遗传因素的其他方面，以确定预防成人肥胖的有希望的机制和创新方法。在美国，日益增长的肥胖流行病提高了我们对如何预防成人型肥胖的理解的必要性。我们正在响应PA-06-256（肥胖症的探索性/发展性临床研究拨款），在两项大型现有前瞻性队列研究——哈佛校友健康研究和女性健康研究中，将成人发病肥胖作为一个新的终点。我们将仔细评估身体活动、缺乏身体活动和饮食在预防最初非肥胖的中老年男性和女性成人发病肥胖和长期体重增加中的作用。该建议产生的临床相关结果将有助于将肥胖作为这两项大型队列研究的可行终点，并为将研究扩展到其他机制相关的生物标志物、遗传因素和肥胖一级预防的风险因素提供机会。

DESCRIPTION (provided by applicant): The growing obesity epidemic in the US has heightened the importance of its primary prevention across all ages; however, prevention efforts generally focus upon community-based intervention studies in pediatric settings or clinical intervention studies among already overweight or obese adults. Obesity commonly develops during adulthood and necessitates an improved understanding of long- term strategies to prevent adult-onset obesity. The epidemiologic literature is limited regarding specific types or intensities of physical activity beyond total physical activity, as well as dietary patterns that may be associated with the development of obesity and long-term weight gain during middle and late adulthood. Therefore, this revised proposal responds to PA-06-256 (Exploratory/Developmental Clinical Research Grants in Obesity) and seeks to develop incident obesity as a new endpoint within two large existing prospective cohort studies of men and women. The Harvard Alumni Health Study includes 12,805 men aged e55 years who completed a baseline questionnaire in 1988 along with 10 years of follow-up, and the Women's Health Study consists of 39,876 women aged e45 years with baseline information in 1992 plus more than 12 years of follow-up for the development of obesity and long-term weight gain. In this proposal, we will carefully evaluate the roles of physical activity, physical inactivity, and diet in the prevention of adult-onset obesity and long-term weight gain in initially non- obese men and women. Our first primary aim will examine whether physical inactivity is associated with an increased risk of becoming obese or greater increases in body weight during long-term follow- up. We will also examine the type (e.g. walking and other common forms of exercise), frequency, and intensity (e.g. moderate, vigorous) of physical activity. Second, we will determine whether specific dietary factors (e.g. Western versus prudent dietary patterns, fruits and vegetables, fiber, carbohydrates, dairy products, and alcohol) are associated with an increased risk of becoming obese or greater increases in body weight. Finally, we will determine whether the above associations are modified by the presence or absence of intermediate clinical factors such as hypertension, diabetes, hypercholesterolemia, or parental history of obesity (available in men only). We have excellent power to assess our hypotheses to draw clinically meaningful conclusions regarding the role of different types and intensities of physical activity, sedentary behaviors, and dietary factors in the primary prevention of obesity. With the successful development of adult-onset obesity and long-term weight gain in these cohorts, we hope this proposal will lead to larger R01 grants with greater scope to examine additional aspects of physical activity, physical inactivity, diet, and related biomarkers and genetic factors to identify promising mechanisms and innovative approaches for the prevention of obesity in adults. PUBLIC HEALTH RELEVANCE: Project Narrative The growing obesity epidemic in the US has heightened the need to improve our understanding of how to prevent adult-onset obesity. We are responding to PA-06-256 (Exploratory/Developmental Clinical Research Grants in Obesity) to develop adult-onset obesity as a new endpoint in two large existing prospective cohort studies, the Harvard Alumni Health Study and the Women's Health Study. We will carefully evaluate the roles of physical activity, physical inactivity, and diet in the prevention of adult-onset obesity and long-term weight gain in initially non-obese middle-aged and older men and women. The clinically relevant results generated from this proposal will help establish obesity as a viable endpoint in these two large cohort studies and provide an opportunity to expand research to other mechanistically relevant biomarkers, genetic factors, and risk factors in the primary prevention of obesity.