Dietary Carbohydrate and Internal Body Fat
关键词
抽象
描述
Obesity, and high internal fat storage in particular, represents a tremendous and increasing health challenge across the world, and is linked to the recent introduction and globalization of an ultra-processed food supply largely based on refined carbohydrates. However, more high-quality studies are needed to directly assess the role of carbohydrate quality in abdominal adiposity. We also need studies with greater long-term adherence to prescribed food profiles, which may be achievied with the help of new electronic tools such as meal planning applications.
The participants select and plan all meals among a list of carefully designed options, using an application/recipe booklet developed for the study. Each recipe/meal/snack is designed to fully comply with the overall macronutrient- and dietary profile for the respective groups. We will further instruct the participants to record their meal choices during three days every 14 days, and to record all deviations throughout the intervention.
Enrolled participants are invited to study visits at baseline and after 3, 6, 9, 12 and 24 months. At all or some of these time points, the participants provide biological samples (blood, urine and feces, and for some, adipose and/or muscle tissue) and undergo phenotyping, e.g., measurement of body weight and fat mass by bioelectrical impedance analysis and low-radiation CT imaging, and a standardized meal test with blood sample collection up to 4 hours postprandially. In addition, participants will be asked to fill out a collection of questionnaires that assess quality of life, motivation, fatigue, gastrointestinal health, appetite and physical activity. We ask the participants to maintain the same level of physical activity throughout the study.
The primary outcome measure is change in internal body fat mass (visceral adipose tissue) measured by CT imaging. Secondary outcome measures include change in 2-hour postprandial serum concentrations of insulin, change in 4-hour postprandial serum concentrations of triacylglycerols, and change in fecal microbiota composition measured by 16S sequencing.
日期
最后验证: | 09/30/2019 |
首次提交: | 08/22/2017 |
提交的预估入学人数: | 01/08/2018 |
首次发布: | 01/16/2018 |
上次提交的更新: | 10/08/2019 |
最近更新发布: | 10/10/2019 |
实际学习开始日期: | 01/02/2018 |
预计主要完成日期: | 04/30/2020 |
预计完成日期: | 03/31/2021 |
状况或疾病
干预/治疗
Behavioral: Acellular carbohydrate diet
Behavioral: Cellular carbohydrate diet
Behavioral: Low-carbohydrate high-fat diet
相
手臂组
臂 | 干预/治疗 |
---|---|
Active Comparator: Acellular carbohydrate diet Prescribed dietary pattern. Carbohydrates from acellular sources, e.g., refined flour/bakery products, at least 500 grams of fruits/vegetables per day, and a macronutrient composition within typical nutritional recommendations for the general population. | Behavioral: Acellular carbohydrate diet Participants will be asked to consume 2,000 - 2,500 kcals, thereof 45 energy percent (E%) carbohydrate (up to 5 E% added sugar), 30 E% fat (10-12 E% saturated fatty acids and 7-10 E% polyunsaturated fatty acids) and 17 E% protein. They will use an original online/smartphone application that provides choices of meals/food combinations/recipes corresponding to their prescribed macronutrient profile and dietary pattern. Participants are asked to complete 3-day dietary records every 14 days throughout the study, and to report any deviations from the planned interventions. |
Experimental: Cellular carbohydrate diet Prescribed dietary pattern. Carbohydrates from cellular sources, e.g., root vegetables, fruits, whole-grain rice, non-flour grain products, at least 500 grams of fruits/vegetables per day, and a macronutrient composition within typical nutritional recommendations for the general population similar to the acellular carbohydrate diet. | Behavioral: Cellular carbohydrate diet Participants will be asked to consume 2,000 - 2,500 kcals, thereof 45 energy percent (E%) carbohydrate (up to 1 E% added sugar), 38 E% fat (10-12 E% saturated fatty acids and 7-10 E% polyunsaturated fatty acids) and 17 E% protein. They will use an original online/smartphone application that provides choices of meals/food combinations/recipes corresponding to their prescribed macronutrient profile and dietary pattern. Participants are asked to complete 3-day dietary records every 14 days throughout the study, and to report any deviations from the planned interventions. |
Experimental: Low-carbohydrate high-fat diet Prescribed dietary pattern. Energy largely from fat, cellular carbohydrate sources, and otherwise similar food types as in the acellular/cellular carbohydrate diets including at least 500 grams of fruits/vegetables per day. | Behavioral: Low-carbohydrate high-fat diet Participants will be asked to consume 2,000 - 2,500 kcals, thereof 10 energy percent (E%) carbohydrate (up to 1 E% added sugar), 73 E% fat (30 E% saturated fatty acids and 7-10 E% polyunsaturated fatty acids) and 17 E% protein. They will use an original online/smartphone application that provides choices of meals/food combinations/recipes corresponding to their prescribed macronutrient profile and dietary pattern. Participants are asked to complete 3-day dietary records every 14 days throughout the study, and to report any deviations from the planned interventions. |
资格标准
有资格学习的年龄 | 20 Years 至 20 Years |
有资格学习的性别 | All |
接受健康志愿者 | 是 |
标准 | Inclusion Criteria: - Body-mass index (BMI) equal to or above 30 kg/m2 and/or waist circumference equal to or above 102 cm for men and 88 cm for women - Weight stable during the last 2 months before start of the study (less than 5 % change in body weight up or down) - No known diabetes or consumption of diabetes medication - Desire to follow a specified dietary pattern using specific recipes throughout the time of the study period - Ability to periodically record food intake using a specially designed app for the study Exclusion Criteria: - Use of statins and/or diabetes medication - Recent surgical or antibiotics treatment during the last 2 months before start of the study - Chronic inflammatory bowel disease - Serious disease - Smoking - Pregnancy or breast feeding - Alcohol consumption during the study of more than 2 alcohol units per day (1 unit = 15 ml (12.8 g) pure alcohol) |
结果
主要结果指标
1. Change in internal body fat [Baseline and 6, 12 and 24 months]
次要成果指标
1. Change in postprandial insulin [Baseline and 3, 6, 9, 12 and 24 months]
2. Change in postprandial C-peptide [Baseline and 3, 6, 9, 12 and 24 months]
3. Change in postprandial triacylglycerol [Baseline and 3, 6, 9, 12 and 24 months]
4. Change in postprandial area under the curve (AUC) glucose [Baseline and 3, 6, 9, 12 and 24 months]
5. Change in postprandial non-esterified fatty acids [Baseline and 3, 6, 9, 12 and 24 months]
6. Change in fecal microbiome composition [Baseline and 3, 6, 9, 12 and 24 months]
7. Change in liver density [Baseline and 6, 12 and 24 months]
8. Change in pericardial fat mass [Baseline and 6, 12 and 24 months]
9. Change in abdominal subcutaneous fat mass [Baseline and 6, 12 and 24 months]
10. Change in coronary artery calcification (CAC) [Baseline and 6, 12 and 24 months]
11. Change in waist circumference [Baseline and 3, 6, 9, 12 and 24 months]
12. Change in body-mass index [Baseline and 3, 6, 9, 12 and 24 months]
13. Change in fasting insulin [Baseline and 3, 6, 9, 12 and 24 months]
14. Change in fasting C-peptide [Baseline and 3, 6, 9, 12 and 24 months]
15. Change in fasting TAG [Baseline and 3, 6, 9, 12 and 24 months]
16. Change in fasting HDL cholesterol [Baseline and 3, 6, 9, 12 and 24 months]
17. Change in TAG/HDL-C ratio [Baseline and 3, 6, 9, 12 and 24 months]
18. Change in fasting LDL cholesterol [Baseline and 3, 6, 9, 12 and 24 months]
19. Change in apolipoprotein profile [Baseline and 3, 6, 9, 12 and 24 months]
20. Change in circulating and urine metabolites associated with one-carbon metabolism [Baseline and 3, 6, 9, 12 and 24 months]
21. Change in total fat mass [Baseline and 3, 6, 9, 12 and 24 months]
22. Change in lean mass [Baseline and 3, 6, 9, 12 and 24 months]
23. Change in appetite/fullness [Baseline and 3, 6, 9, 12 and 24 months]
24. Change in gastrointestinal symptoms by the Roma III questionnaire [Baseline and 3, 6, 9, 12 and 24 months]
25. Change in gastrointestinal symptoms by the IBS-SSS questionnaire [Baseline and 3, 6, 9, 12 and 24 months]
26. Change in fatigue [Baseline and 3, 6, 9, 12 and 24 months]
27. Change in perception of health / quality of life [Baseline and 3, 6, 9, 12 and 24 months]
28. Change in quality of life related to gastrointestinal symptoms [Baseline and 3, 6, 9, 12 and 24 months]