LONGITUDINAL PREDICTORS OF WEIGHT GAIN

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 在美国和世界各地，肥胖是一个严重且日益严重的公共健康问题。虽然所有人都可能在某个时间或其他时间出现短暂的正能量平衡，但一些人能够抵抗环境压力导致体重增加，保持长期的瘦状态。这一建议的中心论点是，了解个体对过度喂养所产生的短期正能量平衡的反应(新陈代谢、能量和行为)，可能为了解在当前环境中促进或防止体重增加的生物机制提供线索。虽然长期的控制性过度喂养实验已经进行了很多年，但以前还没有系统地研究过短期过度喂养对饮食脂肪氧化、过度喂养后的自发食物摄入量或体力活动的直接测量的影响。此外，以前还没有研究过这些变量与随后体重增加之间的关系。据推测，那些在过度喂养后优先氧化饮食脂肪、减少食物摄入量和增加体力活动的个体将随着时间的推移保持苗条的表型。相反，那些未能做出这些适应的人，随着时间的推移，体重往往会增加。这项拟议的研究将考察控制优卡饮食或3天喂食140%基础能量的影响1.饮食脂肪示踪物的氧化2.饥饿、饱腹感、进食欲望和自发食物摄入量3.直接测量的体力活动水平，在一组男性和女性中，这些人可能保持苗条的表型，其他人则是因为有增加体重的倾向而被选中。然后，队列将被跟踪3年，以确定每个受试者的体重增加率。基线测量将与随后的体重增加相关联，以努力确定哪些对过度喂养的适应性反应与纵向确定的体重增加最相关。通过采用一种全面的方法来检查对过度喂养和未来体重变化的反应，拟议的研究应该有助于澄清动态平衡调节机制如何协调地对短期正能量平衡状态做出反应。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Obesity is a serious and growing public health problem in the United States and around the world. While brief periods of positive energy balance likely occur in all people at one time or another, some individuals are able to resist environmental pressure towards weight gain, maintaining a chronic state of thinness. The central thesis of this proposal is that understanding the responses (metabolic, energetic, and behavioral) of individuals to short periods of positive energy balance produced by overfeeding, may provide clues as to the biologic mechanisms that either promote or protect against weight gain in the current environment. While long term controlled overfeeding experiments have been done for many years, no previous studies have systematically examined the effects of short-term overfeeding on direct measures of dietary fat oxidation, post overfeeding spontaneous food intake, or physical activity. Further, no previous study has examined the relationship between these variables and subsequent weight gain. It is hypothesized that those individuals who preferentially oxidize dietary fat, reduce food intake and increase physical activity following overfeeding will maintain a thin phenotype over time. Conversely, those who fail to make these adaptations will tend to gain weight over time. The proposed studies will examine the effects of a controlled eucaloric diet or 3 days of feeding 140% of basal energy on 1. The oxidation of 2 dietary fat tracers 2. Hunger, satiety, desire to eat and spontaneous food intake 3. Directly measured levels of physical activity, in a cohort of men and women enriched in individuals likely to maintain a thin phenotype and others selected for a propensity to gain weight. The cohort will then be followed for 3 years to determine the rate of weight gain in each subject. Baseline measures will be correlated with subsequent weight gain in an effort to define which adaptive responses to overfeeding best correlate with longitudinally determined weight gain. By taking a comprehensive approach to examining the responses to overfeeding and future weight changes, the proposed studies should help clarify how homeostatic regulatory mechanisms coordinately respond to a state of short-term positive energy balance.