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The Effect of Flexitarian, Time-restricted Eating on Cardiometabolic Traits in Normal Weight, Young Men

The Effect of Flexitarian, Time-restricted Eating on Cardiometabolic Traits in Normal Weight, Young Men: a Factorial Randomized Controlled Trial (FlexiFast Study)

Status
UNKNOWN
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05762263
Acronym
FlexiFast
Enrollment
96
Registered
2023-03-09
Start date
2023-04-01
Completion date
2023-12-31
Last updated
2023-11-07

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Blood Pressure, Cardiometabolic Syndrome, Glucose Metabolism Disorders, Lipid Metabolism Disorders

Brief summary

The goal of this factorial randomized controlled trial is to find out whether time-restricted eating and flexitarian diet (on its own and combined) can improve cardiometabolic health markers in normal weight, young men with metabolic abnormalities? Participants will be assigned to four groups: control, flexitarian, time-restricted eating and time-restricted eating + flexitarian. Investigators will look for men with elevated fasting blood glucose or blood lipids level or blood pressure and with normal body weight and waistline. Participants from the flexitarian group will be asked to follow a diet that has been carefully designed for them by the PI and dietitian for the period of 8 weeks. Participants from the control group will receive general healthy eating recommendations. We aim to investigate if the experiment had any effect on changes in metabolic, inflammation and nutritional markers, blood pressure and body weight and composition. Also, the effect of diets on men's sleep, general wellbeing and satisfaction with treatment will be investigated. The proposed study can test a potentially effective nutritional intervention which is feasible to adopt and sustainable (in line with recent planetary diet recommendations). Confirming its effectiveness can fill the research gap, providing new knowledge and approach to the prevention and treatment of metabolic abnormalities in young, lean men.

Interventions

BEHAVIORALDietary

Depending on the allocation arm, participants will be advised to follow a particular dietary plan (either flexitarian eating, time-restricted eating or both combined).

Sponsors

University of Warmia and Mazury in Olsztyn
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
FACTORIAL
Primary purpose
PREVENTION
Masking
NONE

Eligibility

Sex/Gender
MALE
Age
18 Years to 40 Years
Healthy volunteers
Yes

Inclusion criteria

* Males * Age 18-40 years * Normal body weight * At least one of metabolic abnormalities (elevated fasting glucose level - but not diabetes, elevated blood lipids, elevated blood pressure)

Exclusion criteria

* Females * Age \<18 and \>40 years * Overweight or obesity (BMI\>25 kg/m2) * WC \> 94cm * Alcohol \>14 units/week * Smoking * On medication * Diabetes or other chronic diseases * Vegetarians or vegans * Don't own or unable to use a Smartphone with Apple iOS or Android OS

Design outcomes

Primary

MeasureTime frameDescription
Change in glucose homeostasisbaseline, after 8 weeks and after 20 weeks from baselineChange in fasting glucose concentration \[mg/dL\]. Blood samples will be collected after the overnight fast and the analysis will be performed on the Cobas Integra 400 plus analyzer.

Secondary

MeasureTime frameDescription
Change in body fat mass percentagebaseline, after 8 weeks and after 20 weeks from baselineDetermination of body fat percentage will be performed using SECA® mBCA 515 analyser
Change in inflammatory markers-2baseline, after 8 weeks and after 20 weeks from baselineC-reactive protein (CRP) \[mg/L\] - COBAS Integra 400 Plus analyser
Change in nutrition markers-1baseline, after 8 weeks and after 20 weeks from baselineHomocysteine \[μmol/L\] - COBAS Integra 400 Plus analyser
Change in nutrition markers-2baseline, after 8 weeks and after 20 weeks from baselineVitamin B12 \[pg/mL\] - COBAS e411 analyser
Change in insulin concentrationbaseline, after 8 weeks and after 20 weeks from baselineInsulin \[units/mL\] - COBAS e411 analyser
Change in haemoglobin glycosylated (HbA1c) concentrationbaseline, after 8 weeks and after 20 weeks from baselineHbA1c \[mmol/l\] - COBAS e411 analyser
Change in systolic and diastolic blood pressurebaseline, after 8 weeks and after 20 weeks from baselineThe assessment of blood pressure (in mmHg) will be performed prior to and immediately after the intervention using electronic monitor (Omron M3 Intellisense Automatic Blood Monitor, Omron Healthcare, Mannheim, Germany).
Change in total cholesterol (TC)baseline, after 8 weeks and after 20 weeks from baselineThe blood serum concentration of total cholesterol (in mmol/L). Blood samples will be collected after the overnight fast and the analysis will be performed on the Cobas Integra 400 plus analyzer.
Change in high-density lipoprotein (HDL) cholesterolbaseline, after 8 weeks and after 20 weeks from baselineThe blood serum concentration of high-density lipoprotein cholesterol (in mmol/L). Blood samples will be collected after the overnight fast and the analysis will be performed on the Cobas Integra 400 plus analyzer.
Change in low-density lipoprotein (LDL) cholesterolbaseline, after 8 weeks and after 20 weeks from baselineThe blood serum concentration of low-density lipoprotein cholesterol (in mmol/L). Blood samples will be collected after the overnight fast and the analysis will be performed on Cobas Integra 400 plus analyzer.
Change in serum triglycerides (TG)baseline, after 8 weeks and after 20 weeks from baselineThe concentration of serum triglycerides (in mmol/L). Blood samples will be collected after the overnight fast and the analysis will be performed on Cobas Integra 400 plus analyzer.
Change in body weightbaseline, after 8 weeks and after 20 weeks from baselineBody weight (in kg) will be measured using a digital medical scale witl stadiometer.
Change in body mass index (BMI)baseline, after 8 weeks and after 20 weeks from baselineThe measured values of body height and weight will be used for the calculation of body mass index (in kg/m\^2).
Change in waist circumferencebaseline, after 8 weeks and after 20 weeks from baselineWaist circumference measuring (in cm) will be performed using a non-strechable measuring tape.
Change in waist-to-hip ratiobaseline, after 8 weeks and after 20 weeks from baselineThe waist-to-hip ratio will be calculated from the measured values of waist and hip circumferences: waist circumference (cm) / hip circumference (cm).
Change in visceral adipose tissue (VAT)baseline, after 8 weeks and after 20 weeks from baselineDetermination of abdominal fat volume will be measured in litres and performed using SECA® mBCA 515 analyser
Change in inflammatory markers-1baseline, after 8 weeks and after 20 weeks from baselineinterleukin-6 \[pg/mL\] - COBAS e411 analyser

Other

MeasureTime frameDescription
Change in cardiorespiratory fitnessbaseline, after 8 weeks and after 20 weeks from baselineOxygen consumption (VO2) measured using ergospirometer CORTEX MetaMax 3b (ml oxygen/kg of body weight/minute). VO2 max is the maximum amount of oxygen the body can utilize during exercise.
Change in physical activity levelbaseline, after 8 weeks and after 20 weeks from baselineMeasured using smartbands with pedometers (number of daily steps)
Participant's satisfaction with treatment upon completionafter 8 weeksSatisfaction with treatment: DSat-28 questionnaire (10.1002/osp4.299)
Change in dietary behavioursbaseline, after 8 weeks and after 20 weeks from baselineDietary habits will be assessed using KomPAN questionnaire (https://doi.org/10.3390/nu10121845)
Change in sleep lengthbaseline, after 8 weeks and after 20 weeks from baselineMeasured using smartbands with sleep trackers: length (in hours)
Change in sleep qualitybaseline, after 8 weeks and after 20 weeks from baselineMeasured using smartbands with sleep trackers: with metrics specific to the selected model (score).

Countries

Poland

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026