Intermittent Fasting in Shift-work
Conditions
Keywords
time-restricted eating, shiftwork, intermittent fasting, healthcare
Brief summary
The goal of this clinical trial is to learn about the effect of time-restricted eating (TRE) to 10 hours per day on glucose homeostasis, markers of the circadian system, homeostatic and hedonic regulation of appetite, and inflammation/oxidative stress status in night shift workers. The main questions it aims to answer are: 1) How does a time-restricted eating protocol affect glucose homeostasis in shift workers? and 2) How does a time-restricted eating protocol affect markers of the circadian system, homeostatic and hedonic regulation of appetite, and inflammation/oxidative stress status in shift workers? Participants will be asked to follow a TRE protocol on which they must restrict their eating to a self-selected time window of 10 hours a day, with mandatory fasting time between 24:00-06:00h. for 8 weeks. Researchers will compare the intervention with an additional period of 8 weeks, in which the participants will follow their usual diet without any time restriction, to see if the intervention improves glucose regulation appetite and markers of circadian system, homeostatic and hedonic regulation of appetite, and inflammation/oxidative stress.
Detailed description
This is a randomized, crossover, controlled, within-subject study. After recruitment, participants will be randomized to one of two conditions: i) Time-restricted eating (TRE), with an eating window of 10 hours per day but without any other diet modification (e.g., types of food or amount of energy consumed). Each participant can freely choose the starting time of their eating window. If a participant need to make modifications to the start time of their eating window, he/she may do so only once during the TRE period, and the research team must be informed. After a washout period of at least 30 days, participants will undergo ii) Regular eating (REG), during which the participants must maintain their usual eating pattern (i.e., usual eating window), without making any dietary or lifestyle changes. Each condition will have a duration of 8 weeks. Randomization will be done using computer-generated random numbers.
Interventions
BEHAVIORALTime-restricted eating
During the intervention (TRE) each participant will freely choose the starting time of their eating window. If needed, participant can modify the selected start time of their eating window only once during the intervention period, and the research team must be informed. After a washout period of at least 30 days, participants will undergo the opposite condition (TRE or Regular eating) after the initial randomization
Sponsors
University of Chile
Agencia Nacional de Investigación y Desarrollo
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
PREVENTION
Masking
SINGLE (Investigator)
Eligibility
Sex/Gender
ALL
Age
18 Years to 60 Years
Healthy volunteers
Yes
Inclusion criteria
Adults (range 18 - 60 yrs.) Men and women Performing as a healthcare worker Being a shift-worker for at least 6 months in the current schedule Working in rotating shiftwork, including at least one night shift Reporting no work-related performance difficulties
Exclusion criteria
* Current and chronic neurological disorders * Pathologies related to abnormal adrenal activity * Liver or kidney disease * Uncontrolled hypertension, dyslipidemia, and thyroid disease * Insulin resistance and T2D * BMI ≥40 kg/m2 * Use of medications known to alter body composition, such as insulin sensitizers, glucocorticoids, or anti-depressants * Autoimmune diseases with acute symptoms; recent surgery of any kind (in the last 3 months); * Acute, chronic inflammation (usCRP \>10 mg/L) * Following any dietary restriction (special diet) in the previous three months * Having a short sleep (habitual sleep duration of less than 6h per day) * History of bariatric surgery * Depression (Beck Depression Inventory) or sleep disorders (Pittsburgh Sleep Questionnaire) * Night-eating syndrome (Night Eating Questionnaire) * Intense exercise level (\>3 days/week of high-intensity exercise) * Having traveled across time zones (at any time during the last month) and planning travel during the study * Pregnant or intend to become pregnant, and * Lactating women
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change from Baseline in the mean fasting glycemia at 8 weeks | From baseline to the end of treatment (at 8 weeks), in each study period (TRE and REG) | Fasting glycemia level (in mg/dL) will be measured from fasting blood samples and measured with the hexokinase method |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change from baseline to end of treatment (8weeks) in 24-h glycemic control | From baseline to the end of treatment (at 8 weeks), in each study period (TRE and REG) | 24-h glycemic control (expressed in mg/dL), measured with continuous glucose monitoring (CGM) using a portable capillary glucose sensor, over 10 consecutive days. |
| 24-hour motor activity level (counts/min) | From enrollment to the end of treatment (at 8 weeks), in each study period (TRE and REG) | Motor activity will be assessed by accelerometric recordings (actigraphic data) of wrist activity. Actigraphy data will assess motor activity before and after the intervention |
| Change from Baseline in the circadian clock-genes expression at 8 weeks | From baseline to the end of treatment (at 8 weeks), in each study period (TRE and REG) | Clock-gene expression will be evaluated by relative expression, performing RT-stem loop real-time PCR, from fasting whole-blood samples taken at baseline and after 8 weeks, in each study period. Gene expression levels of the target sequences will be normalized to the expression of GAPDH, and will be calculated by applying equation 2-∆∆ CT. |
| Change from baseline in thiobarbituric acid reactive substances (TBARS) level at 8 weeks | From baseline to the end of treatment (8 weeks) in each study period (TRE and REG)] | TBARS level (in µM/ml) will be measured in plasma samples |
| Change from baseline in F-8 isoprostane level at 8 weeks | From baseline to the end of treatment (8 weeks) in each study period (TRE and REG) | F-8 isoprostane level (in pg/mL) will be measured in plasma samples |
| Change from Baseline in Appetite-related feelings at 8 weeks | From baseline to the end of treatment (8 weeks) in each study period (TRE and REG) | A visual analog scale will be used to assess appetite feeling levels. Each participant rates their subjective feelings of appetite, satiety, and desire to eat using a 100 mm visual analog scale, with endpoints indicating from "not at all" (0 mm) to "extremely" (100 mm). |
| Change from baseline in total-, reduced- and oxidized glutathione levels at 8 weeks | From baseline to the end of treatment (8 weeks) in each study period (TRE and REG) | Total-, reduced-, and oxidized glutathione levels (in µM) will be measured in plasma samples |
| Change from baseline in C-reactive protein levels at 8 weeks | From baseline to the end of treatment (8 weeks) in each study period (TRE and REG) | C-reactive protein levels (in mg/L) will be measured in serum samples |
| Change from baseline in pro-inflammatory cytokine levels at 8 weeks | From baseline to the end of treatment (8 weeks) in each study period (TRE and REG) | Interleukin 1β, Interleukin 6, and Tumor necrosis factor (TNF-α) levels (in pg/mL) will be measured in plasma samples. |
Countries
Chile
Contacts
STUDY_CHAIRLucía Cifuentes, MD
Ethics Committee for Human Subjects of the Faculty of Medicine, University of Chile
Outcome results
None listed