POPULAR DIETS, METABOLISM, AND CVD RISK

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。 具体目标#1：评估三种主要饮食--传统低脂、低脂/低血糖指数和极低碳水化合物--对肥胖年轻人减肥后能量消耗的影响 假设： 1与低脂/低血糖指数饮食或极低碳水化合物饮食相比，在传统低脂饮食期间，减肥后的能量消耗会更低。 1B休息时间和总能量消耗在低脂/低血糖指数饮食和极低碳水化合物饮食之间没有差别。 主要终点：禁食状态下用间接量热法测定静息能量消耗。 次要终点：使用双标记水方法的总能量消耗；使用间接量热法测量食物的热效应；使用加速度法测量体力活动。 具体目标#2：评估三种主要饮食对肥胖成年人其他生理适应减肥的影响 假设： 2与低脂/低糖指数饮食或极低碳水化合物饮食相比，在传统低脂饮食期间，从生理适应到体重减轻的变化将更大。 2B低脂/低血糖指数饮食和极低碳水化合物饮食在减肥生理适应方面的变化没有差别。 主要终点：血清T3浓度。 次级终点：其他甲状腺功能(T4、反T3、TSH、THBG)、生长激素作用的测量(IGF-1)、生殖激素(黄体生成素、卵泡刺激素、睾酮、雌二醇)、应激激素(24小时尿皮质醇)、饥饿感。 具体目标#3：评估肥胖青年减肥后三种主要饮食对心血管疾病危险因素的影响。 假设： 3A胰岛素抵抗在低脂/低血糖指数饮食中比极低碳水化合物饮食或传统低脂饮食更低(更高的胰岛素敏感性)。

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. Specific Aim #1: To evaluate the effects of three dominant diets - conventional low-fat, low-fat/low-glycemic index and very-low-carbohydrate - on energy expenditure following weight loss in obese young adults Hypotheses: 1a Energy expenditure following weight loss will be lower during the conventional low-fat diet compared to either the low-fat/low-glycemic index diet or the very-low-carbohydrate diet. 1b Resting and total energy expenditure will not differ between the low-fat/low-glycemic index diet and the very-low-carbohydrate diet. Primary endpoint: resting energy expenditure using indirect calorimetry in the fasting state. Secondary endpoints: total energy expenditure using doubly labeled water methodology; thermic effect of food using indirect calorimetry; physical activity using accelerometry. Specific Aim #2: To evaluate the effects of three dominant diets on other physiological adaptations to weight loss in obese adults Hypotheses: 2a Changes from baseline in physiological adaptations to weight loss will be greater during the conventional low-fat diet compared to either the low-fat/low-glycemic index diet or the very-low-carbohydrate diet. 2b Changes in the physiological adaptations to weight loss will not differ between the low-fat/low-glycemic index diet and the very-low-carbohydrate diet. Primary endpoint: serum T3 concentration. Secondary endpoints: Other thyroid functions (T4, reverse T3, TSH, THBG), measures of growth hormone action (IGF-1), reproductive hormones (LH, FSH, testosterone, estradiol), stress hormones (24-hr urinary cortisol), hunger. Specific Aim #3: To evaluate the effects of three dominant diets on cardiovascular disease risk factors following weight loss in obese young adults. Hypotheses: 3a Insulin resistance will be lower (greater insulin sensitivity) during the low-fat/low-glycemic index diet compared to either the very-low-carbohydrate diet or the conventional low-fat.