A Randomized, Cross-Over Trial on the Effects of a Low-Fat Vegan Diet Versus a Mediterranean Diet on Body Weight
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 62
- 试验地点
- 2
- 主要终点
- Insulin sensitivity
研究概览
简要总结
This randomized, cross-over trial aims to assess changes in body weight, plasma lipids, insulin sensitivity, and postprandial metabolism with a low-fat, plant-based diet and a Mediterranean diet, both followed for 4 months.
详细描述
In a 36-week cross-over trial, overweight adults will consume a low-fat vegan diet and a Mediterranean diet in two separate 16-week phases. Changes in body weight will be the primary dependent variable. In addition, plasma lipid concentrations, insulin sensitivity, and postprandial metabolism will also be assessed and changes over time will be compared between the two diets.
Participants will be randomly assigned to start either a low-fat vegan diet or a Mediterranean diet for 16 weeks. Both groups will receive weekly classes and support, and will be asked to make no changes to their exercise patterns for the study period. After a 4-week washout period, participants will cross over to the second dietary intervention for another 16 weeks.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Treatment
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Men and women age ≥18 years of age
- •Body mass index 28-40 kg/m2
排除标准
- •Diabetes mellitus type 1, history of any endocrine condition that would affect body weight, such as thyroid disease, pituitary abnormality, or Cushing's syndrome
- •Smoking during the past six months
- •Alcohol consumption of more than 2 drinks per day or the equivalent, episodic increased drinking (e.g., more than 2 drinks per day on weekends), or a history of alcohol abuse or dependency followed by any current use
- •Use of recreational drugs in the past 6 months
- •Use within the preceding six months of medications that affect appetite or body weight, such as estrogens or other hormones, thyroid medications (unstable dose within the preceding 6 months), systemic steroids, antidepressants (tricyclics, MAOIs, SSRIs), antipsychotics, lithium, anticonvulsants, appetite suppressants or other weight-loss drugs, herbs for weight loss or mood, St. John's wort, ephedra, beta blockers
- •Pregnancy or intention to become pregnant during the study period, as verified by self--- - Unstable medical or psychiatric illness
- •Evidence of an eating disorder
- •Likely to be disruptive in group sessions
- •Already following a low-fat vegan diet or Mediterranean diet
- •Lack of English fluency
- •Inability to maintain current medication regimen
- •Inability or unwillingness to participate in all components of the study
- •Intention to follow another weight-loss method during the trial
研究组 & 干预措施
Plant-based diet
The diet group will be asked to follow a low-fat, vegan diet for 16 weeks.
干预措施: Plant-based diet (Other)
Mediterranean diet
The diet group will be asked to follow a Mediterranean diet for 16 weeks.
干预措施: Mediterranean Diet (Other)
结局指标
主要结局
Insulin sensitivity
时间窗: Change in insulin sensitivity from Baseline at 4 months
Insulin sensitivity will be assessed by the HOMA index.
Body weight
时间窗: Change in body weight from Baseline at 4 months
Body weight will be assessed at the baseline and at the completion of both interventions.
Metabolism
时间窗: Changes in metabolism from Baseline at 4 months
Participants will be asked to report to the laboratory within 60 minutes of waking and after a 12-hour fast. Following 30 minutes of quiet rest in a dimly lit room, pulse, respiratory rate, and body temperature will be measured. REE will be measured for 20 minutes through indirect calorimetry (Cosmed Quark RMR, Chicago, IL) utilizing a ventilated hood system. The laboratory temperature will be maintained at 23 degrees C throughout, and precautions will be taken to minimize any disturbances that could affect the metabolic rate. For premenopausal women, measures will be timed so as to occur in the luteal phase of the menstrual cycle. Postprandial metabolism will be measured for three hours after the standard meal.
Plasma lipids
时间窗: Change in plasma cholesterol, triglycerides, and HbA1c from Baseline at 4 months
Plasma cholesterol, triglycerides, and HbA1c will be measured in a fasting state.
次要结局
- Levels of Advanced Glycosylation Endproducts (AGEs)(Change in Advanced Glycosylation Endproducts (AGEs) from Baseline at 4 months)
- Endothelial function(Change in Endothelial function from Baseline at 4 months)
- Microbiome analysis(Change in Microbiome from Baseline at 4 months)
- Dietary Advanced Glycation End Products (AGEs)(16 weeks)
- PDI, hPDI, uPDI(16 weeks)
- Ultraprocessed foods(16 weeks)
- Carbon Footprint(16 weeks)
- Food costs(16 weeks)