Dietary Composition and Energy Expenditure During Weight-Loss Maintenance
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 234
- 试验地点
- 1
- 主要终点
- Total Energy Expenditure, Assessed by Indirect Calorimetry Using Stable Isotopes
研究概览
简要总结
This study will evaluate the effects of dietary composition on energy expenditure and chronic disease risk factors, while also exploring physiological mechanisms underlying these effects.
详细描述
Many overweight and obese people can lose weight for a few months, but most have difficulty maintaining weight loss over the long term. One explanation for the poor long-term outcome of weight-loss diets relates to behavior, in that motivation to adhere to restrictive regimens typically diminishes with time. An alternative explanation is that weight loss elicits biological adaptations - specifically a decline in energy expenditure and an increase in hunger - that promote weight regain. The purpose of this study is to evaluate the effects of dietary composition on energy expenditure and risk for chronic diseases, while also exploring physiological mechanisms underlying these effects. The study will be performed in collaboration with Framingham State University, providing a novel and feasible method for feeding subjects in dining halls and monitoring compliance.
Following 12±2% weight loss on a standard run-in diet, 150 adults (aged 18 to 65 years) will be randomly assigned to one of three weight-loss maintenance diets controlled for protein content (20% of energy) and varying widely in dietary carbohydrate-to-fat ratio: Low-carbohydrate (20% of energy from carbohydrate, 60% fat), Moderate- carbohydrate (40% carbohydrate, 40% fat), High-carbohydrate (60% carbohydrate, 20% fat). During the weight-loss maintenance phase, energy intake will be adjusted to prevent changes in body weight. The primary outcome will be change in total energy expenditure (indirect calorimetry using stable isotopes) through 20 weeks. Secondary outcomes during weight maintenance will include resting energy expenditure (indirect calorimetry using respiratory gas exchange), physical activity (accelerometry), measures of insulin resistance and skeletal muscle work efficiency, components of the metabolic syndrome, and hormonal and metabolic measures that might inform an understanding of physiological mechanisms. We also will assess weight change during a 2-week ad libitum feeding phase, as an objective measure of dietary effects on hunger. The analytic framework for addressing study hypothesis will be repeated-measures analysis of variance, with adjustment for covariates (sex, race, ethnicity, age, anthropometrics, insulin sensitivity and secretion, obesity-related genes). We also will test each covariate for effect modification (covariate × diet interaction).
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 65 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Aged 18 to 65 years
- •BMI ≥ 25 kg/m2
- •Weight ≤ 425 lbs
- •Medical clearance from a primary care provider
- •Plans to matriculate at Framingham State University (campus-based participants: students), work on campus (campus-based participants: faculty and staff), or live in the greater Framingham area (community-based participants) throughout the academic year of enrollment in the study
- •Academic and social clearance from the FSU Office of Enrollment and Student Development (student participants) or willingness to comply with Criminal Offender Record Information (CORI) check and Sex Offender Registry Information (SORI) check (community-based subjects)
- •Willingness to eat and drink only the foods and beverages on the study menus during participation, with no food allergies or aversions
- •Willingness to eat in the dining hall
- •Willingness to abstain from consuming alcohol during participation
排除标准
- •Change in body weight exceeding ±10% during prior year
- •Recent adherence to a special diet
- •Recent adherence to a vigorous physical activity regimen (e.g., participation in a varsity sport)
- •Chronic use of any medication or dietary supplement that could affect study outcomes
- •Current smoking (1 cigarette in the last week)
- •Heavy baseline alcohol consumption (> 10 drinks/week) or history of binge drinking (≥ 5 drinks in 1 day, anytime in past 6 months)
- •Physician diagnosis of a major medical/psychiatric illness or eating disorder
- •Abnormal HgA1c, TSH, BUN, creatinine; hematocrit < 30; ALT > 200% of normal upper limit
- •Plans for a vacation during the study that would preclude adherence to prescribed diet
- •Additional exclusions for female participants: Irregular menstrual cycles; any change in birth control medication during the 3 months prior to enrollment; pregnancy or lactation during the 12 months prior to enrollment
研究组 & 干预措施
Low carbohydrate diet
Feeding study. Composition (by proportion of calories): 20% carbohydrate, 60% fat, 20% protein
干预措施: Feeding study (Behavioral)
Moderate carbohydrate diet
Feeding study. Composition (by proportion of calories): 40% carbohydrate, 40% fat, 20% protein
干预措施: Feeding study (Behavioral)
High carbohydrate diet
Feeding study. Composition (by proportion of calories): 60% carbohydrate, 20% fat, 20% protein
干预措施: Feeding study (Behavioral)
结局指标
主要结局
Total Energy Expenditure, Assessed by Indirect Calorimetry Using Stable Isotopes
时间窗: Start of Trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance
Total energy expenditure (TEE), assessed by indirect calorimetry using stable isotopes Total calories burned: Participants each drank about a cup of water containing special tracers which are measurable when they pass out of the body through urine. They provided a urine sample before they drank the water and then about every other day for the next two (2) weeks. Change: average (midpoint of test phase, end of test phase) - start of trial
次要结局
- Serum Metabolomics Profile(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- C-reactive Protein (% Change)(Change through 20 weeks' weight loss maintenance)
- IL-6 (Start of Trial)(Start of trial (time of randomization, post-weight loss))
- IL-6 (% Change)(Change through 20 weeks' weight loss maintenance)
- Thyroxine (T4)(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Free T4(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Thyroid Stimulating Hormone(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Reverse T3(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Urinary Cortisol Excretion(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Urinary Catecholamine - Adrenaline(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Urinary Catecholamine - Dopamine(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- C-reactive Protein (Start of Trial)(Start of trial (time of randomization, post-weight loss))
- Urinary Catecholamine - Noradrenaline(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Insulin Sensitivity (Hepatic), Assessed by Frequently-sampled Oral Glucose Tolerance Test(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Insulin Sensitivity (Systemic), Assessed by Frequently-sampled Oral Glucose Tolerance Test(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Non-esterified Fatty Acids(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Serum Ketones/Ketoacids(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Lactate(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Metabolic Fuel Concentration in Serum (Glucose, Nonesterified Fatty Acids, Ketones/Ketoacids, Lactate)(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Triglycerides(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Body Composition (DXA)(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Glucose(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Change in Lipoprotein Particle Subfraction Distribution(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Total Cholesterol(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Gut Microbiome Profile(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Blood Pressure(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Plasminogen Activator Inhibitor-1 (Start of Trial)(Start of trial (time of randomization, post-weight loss))
- HDL-Cholesterol(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Non-HDL-Cholesterol(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- LDL-Cholesterol(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Adiponectin (Start of Trial)(Start of trial (time of randomization, post-weight loss))
- Adiponectin (% Change)(Change through 20 weeks' weight loss maintenance)
- Luteinizing Hormone(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Plasminogen Activator Inhibitor-1 (% Change)(Change through 20 weeks' weight loss maintenance)
- Fibrinogen(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Insulin Secretion Determined as Blood Insulin Concentration 30 Minutes After Oral Glucose (Start of Trial)(Start of trial (time of randomization, post-weight loss))
- Follicle Stimulating Hormone(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Leptin (Start of Trial)(Start of trial (time of randomization, post-weight loss))
- Leptin (% Change)(Change through 20 weeks' weight loss maintenance)
- Ghrelin (Start of Trial)(Start of trial (time of randomization, post-weight loss))
- Ghrelin (% Change)(Change through 20 weeks' weight loss maintenance)
- 1,5-Anhydroglucitol(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Glycemic Control, Assessed by HgA1c(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Resting Energy Expenditure, Assessed by Indirect Calorimetry Using Respiratory Gas Exchange(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Physical Activity, Assessed by Accelerometry(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Skeletal Muscle Work Efficiency(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Body Weight Change During ad Libitum Feeding(Ad libitum feeding period (weeks 21 and 22 following randomization))
- Insulin-like Growth Factor 1 (IGF-1)(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- IGF Binding Proteins(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Testosterone(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Estradiol(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Change in Cognitive Function Related to Memory(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Change in Cognitive Function Related to Processing Speed and Executive Function(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Change in Self-reported Sleep Quality(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Change in Self-reported Depression Measure(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Change in Self-reported Food Addiction Score(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Change in Self-reported Emotional Eating Score(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Change in Self-reported Binge Eating Score(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
- Change in Self-reported Mood/Anxiety(Start of trial (time of randomization, post-weight loss) through 20 weeks' weight loss maintenance)
研究者
David S. Ludwig, MD, PhD
Director, Obesity Prevention Center
Boston Children's Hospital