Overweight and Obesity
Conditions
Keywords
Time-restricted feeding, Meal timing, Obesity, Glycemic control, Blood lipids, Inflammation, Sleep
Brief summary
This human dietary intervention study with a cross-over design aims to compare the effects of two isocaloric diets - early time-restricted feeding (TRF) vs. late TRF - on glycemic control and lipid metabolism in overweight and obese women.
Detailed description
The participants are randomly allocated to one of two study groups: In study group (A) participants will begin with the early TRF (e-TRF) intervention. They will consume their habitual food (and the habitual daily amount of food) between 8 am and 4 pm for two weeks. After a washout-phase participants will conduct the late TRF (l-TRF) and consume their habitual food between 1 pm and 9 pm for another two weeks. Study group (B) receives the same interventions in the reversed order. Both dietary regimens will result in 8-hr eating period and 16-hr fasting period during the 24h day.
Interventions
BEHAVIORALEarly Time-Restricted Feeding
Eat between 8 am and 4 pm for two weeks
BEHAVIORALLate Time-Restricted Feeding
Eat between 1 pm and 9 pm for two weeks
Sponsors
Charite University, Berlin, Germany
Immanuel Krankenhaus Berlin, Germany
Hasso-Plattner Institut, Potsdam, Germany
University of Potsdam
German Institute of Human Nutrition
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
FEMALE
Age
18 Years to 70 Years
Healthy volunteers
No
Inclusion criteria
* BMI 25-35 kg/m²
Exclusion criteria
* prior diagnosis of type 1 or 2 diabetes * weight changes \> 5% within past 3 months * current shift work or history of shift work * traveled across more than one time zone one month before the study * poor quality of sleep (PSQI score\>10) * eating disorders, food intolerance/allergy, severe indigestion * Pregnant or breastfeeding * severe internal or psychiatric disorders or other conditions that might influence the outcome of the study
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Insulin sensitivity | 2 weeks | Assessed using Matsuda index in oral glucose tolerance test (OGTT) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Metabolic hormones and inflammatory markers | 2 weeks | Levels of hormones related to the glucose metabolism, hormones of appetite regulation, adipokines and inflammatory markers |
| Glucose tolerance, fasting glucose, and overall daily glycemic variation | 2 weeks (OGTT) and 14 days (CGM) | Assessed by glucose area under the curve in OGTT and using a continuous glucose monitoring (CGM) |
| Oxidative stress markers | 2 weeks | Malondialdehyde, 3-nitrotyrosine, and protein carbonyls |
| Blood lipids | 2 weeks | Total cholesterol, low-density lipoprotein and high-density lipoprotein cholesterol and triglycerides |
| Blood pressure | 2 weeks | Systolic and diastolic blood pressure |
| Liver enzymes | 2 weeks | γ-glutamyltransferase (GGT), aspartate aminotransferase (ALT), and alanine aminotransferase (AST) |
| Anthropometric parameters: body weight | 2 weeks | Body weight in kilograms |
| Anthropometric parameters: BMI | 2 weeks | BMI in kg/m\^2 |
| Anthropometric parameters: waist circumference | 2 weeks | Waist circumference in centimeters |
| Expression of metabolic genes in adipose tissue | 2 weeks | RNA-Seq analysis of subcutaneous adipose tissue samples |
| Social and economic decision behaviour | 2 weeks | Assessed by computer tests together with the Barratt Impulsiveness Scale short version (BIS-15 with a score between 15 and 60, where higher values correspond to higher impulsiveness) and the UCLA Loneliness Scale (with a score between 20 and 100, where higher values correspond to higher subjectively perceived loneliness) |
| Anthropometric parameters: fat and lean mass | 2 weeks | Fat and lean mass in kilograms assessed by bioelectrical impedance analysis |
| Food intake: eating times | 14 days | Eating times in hours and minutes as assessed by food records |
| Food intake: calorie intake | 14 days | Calorie intake in kilocalories as assessed by food records |
| Food intake: macronutrient composition | 14 days | Macronutrient composition in percentage of energy intake as assessed by food records |
| Satiety and hunger scores | 2 weeks | Assessed using Visual Analog Scales (VAS with a scale of 1-100, where higher values correspond to stronger satiety/hunger) |
| Sleep quality and timing | 2 weeks (PSQI) and 14 days (ActiGraph, sleep diary) | Sleep quality as assessed by the Pittsburgh Sleep Quality Index (PSQI score, which ranges from 0-21, where higher values correspond to worse sleep quality) and by the ActiGraph device; sleep timing (sleep onset and offset) as monitored using a sleep diary |
| Physical activity | 14 days | 24-h physical activity as monitored by an ActiGraph device |
Other
| Measure | Time frame | Description |
|---|---|---|
| Gene expression in peripheral mononuclear blood cells (PBMC) | 2 weeks | mRNA expression of clock, metabolic and inflammatory genes |
| Internal circadian phase | 2 weeks | Circadian phase as assessed using the BodyTime assay in isolated CD14+ blood monocytes |
Countries
Germany
Outcome results
None listed