An interventional study of Time restricted eating in Time Restricted Eating, sponsored by University of Oklahoma. Completed at 1 site in United States. Open to participants aged 21 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-08-17.
Sponsored by University of Oklahoma · Not applicable, Interventional, and Other
The central hypothesis of this study is that closer adherence to time restricted eating (TRE) will improve endothelial function, neurovascular (NVC) responses, resulting in improved cognitive performance, potentially through activation of SIRT1-dependent vasoprotective pathways.
This hypothesis will be tested by assessing the effect of TRE (not more than 10hr eating window each day for 6 months) in healthy adults (≥21 years of age).
148 studies on the registry are indexed under Intermittent Fasting; 68 are open to participants now.
This study's enrollment of 11 is below the median of 60 across 144 interventional studies indexed under Intermittent Fasting.
Browse Intermittent Fasting studies →University of Oklahoma is the lead sponsor of 424 studies on the registry; 99 are open to participants now.
Of its 42 completed or terminated interventional studies of FDA-regulated products, 16 (38%) have results posted.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
14 h of fasting daily (10 h of free eating)
Behavioral: Time restricted eating
14:10 daily fasting regimen
Neurovascular Coupling Using Functional Near Infrared Spectroscopy (fNIRS)
Functional near infrared spectroscopy (fNIRS) will be performed during the cognitive n-back task. fNIRS approach generates data that represent a relative change in oxygenated hemoglobin measured over the cortical brain tissues. fNIRS data is analyzed using a pipeline based on the General Linear Model (GLM) approach created using the Brain AnalyzIR toolbox and implemented in MatLab. At the subject level, regression coefficients (beta values) are extracted to characterize individual neurovascular coupling response in the prefrontal cortex across all n-back blocks. It is expected that more difficult cognitive tasks will lead to increased neurovascular coupling responses in healthy individuals, but no clinically relevant ranges exist for this measure.
Time frame: Baseline, 6 months
Neurovascular Coupling Using the Dynamic Retinal Vessel Analysis
Flicker light-induced dilation of the retinal vessels (percentage increase over baseline diameter) will be measured in the right or left eye of each study participant using the Dynamic Vessel Analyzer (DVA, IMEDOS Systems, Jena, Germany). The change in retinal vessel diameters is tracked and reported as a %change from baseline, before and after treatment.
Time frame: Baseline, 6 months
Neurovascular Coupling Using Transcranial Doppler
Transcranial Doppler sonography will be used to measure the change in the blood flow velocities during the cognitive n-back task between before and after treatment.
Time frame: Baseline, 6 months
Microvascular Endothelial Function
Changes in microvascular endothelial function will be assessed using laser speckle contrast imaging (LSCI) in the hand using the flow mediated dilation approach. The change in skin perfusion is calculated and reported as a fold change from baseline.
Time frame: Baseline, 6 months
Macrovascular Endothelial Function
Changes in macrovascular endothelial function will be assessed using sonography during flow mediated dilation approach. The change in brachial artery diameter is calculated and reported as a %change from baseline.
Time frame: Baseline, 6 months
Deep Tissue Oxygen Saturation
Transcutaneous deep tissue oxygen saturation will be measured using the inSpectra near infrared device. The data are calculated and reported as a %change from baseline.
Time frame: Baseline, 6 months
Arterial Stiffness
The arterial stiffness will be measured using the pulse wave analysis approach (SphygmoCor, Atcor medical, Itasca IL, or similar). Analysis generated the augmentation index which will be used for comparison before and after treatment.
Time frame: Baseline, 6 months
ECG
ECG will be recorded for heart rate variability analysis. The values of high frequency domain, low frequency domain, their ratio, as well as total power will be calculated and used for comparison before and after treatment.
Time frame: Baseline, 6 months
Glycocalyx - Perfused Boundary Region
Video recordings of the sublingual vasculature will be performed using the high definition video camera GlycoCheck (Microvascular health solutions). Data collected will include perfused boundary region (um), and will be used for comparison before and after treatment.
Time frame: Baseline, 6 months
Capillary Density
Video recordings of the sublingual vasculature will be performed using the high definition video camera GlycoCheck (Microvascular health solutions). Data collected will include capillary density (mm/mm\^2), and will be used for comparison before and after treatment.
Time frame: Baseline, 6 months
Red Blood Cell Velocity
Video recordings of the sublingual vasculature will be performed using the high definition video camera GlycoCheck (Microvascular health solutions). Data collected will include red blood cell velocity (um/sec), and will be used for comparison before and after treatment.
Time frame: Baseline, 6 months
Inhibitory Control and Attention
Flanker Inhibitory Control and Attention Test was used to assess inhibitory control and attention. The participant is asked to focus on a particular stimulus while inhibiting attention to the stimuli flanking it. Scores are fully adjusted to nationally representative normative sample of NIH toolbox test takers, accounting for age, sex, race, and education (mean = 50; SD = 10). Higher scores represent better outcomes.
Time frame: Baseline, 6 months
Episodic Memory
Picture Sequence Memory Test was used to assess episodic memory. Participants are shown a number of activities, and then asked to reproduce the sequence of pictures as it was presented to them. Scores are fully adjusted to nationally representative normative sample of NIH toolbox test takers, accounting for age, sex, race, and education (mean = 50; SD = 10). Higher scores represent better outcomes.
Time frame: Baseline, 6 months
Working Memory
List Sorting Working Memory Test was used to assess working memory. The participant is asked to recall and sequence different stimuli that are presented visually and via audio. Scores are fully adjusted to nationally representative normative sample of NIH toolbox test takers, accounting for age, sex, race, and education (mean = 50; SD = 10). Higher scores represent better outcomes.
Time frame: Baseline, 6 months
Language
Picture Vocabulary Test measures receptive vocabulary administered in a computer-adaptive test (CAT) format. Respondents select the picture that most closely matches the meaning of the word. Scores are fully adjusted to nationally representative normative sample of NIH toolbox test takers, accounting for age, sex, race, and education (mean = 50; SD = 10). Higher scores represent better outcomes.
Time frame: Baseline, 6 months
Executive Function
Dimensional Change Card Sort Test was used to assess cognitive flexibility and attention. The participant is asked to match a series of picture pairs to a target picture. Scores are fully adjusted to nationally representative normative sample of NIH toolbox test takers, accounting for age, sex, race, and education (mean = 50; SD = 10). Higher scores represent better outcomes.
Time frame: Baseline, 6 months
Processing Speed
Pattern Comparison Processing Speed Test was used to assess processing speed. Participants are asked to quickly determine whether two stimuli are the same or not the same. Scores are fully adjusted to nationally representative normative sample of NIH toolbox test takers, accounting for age, sex, race, and education (mean = 50; SD = 10). Higher scores represent better outcomes.
Time frame: Baseline, 6 months
| Milestone | Time Restricted Eating |
|---|---|
| Started | 11 |
| Completed | 6 |
| Not completed | 5 |
| Withdrew: Withdrawal by subject | 4 |
| Withdrew: Lost to follow-up | 1 |
Functional near infrared spectroscopy (fNIRS) will be performed during the cognitive n-back task. fNIRS approach generates data that represent a relative change in oxygenated hemoglobin measured over the cortical brain tissues. fNIRS data is analyzed using a pipeline based on the General Linear Model (GLM) approach created using the Brain AnalyzIR toolbox and implemented in MatLab. At the subject level, regression coefficients (beta values) are extracted to characterize individual neurovascular coupling response in the prefrontal cortex across all n-back blocks. It is expected that more difficult cognitive tasks will lead to increased neurovascular coupling responses in healthy individuals, but no clinically relevant ranges exist for this measure.
| Beta value | Baseline | Endpoint |
|---|---|---|
| Neurovascular Coupling Using Functional Near Infrared Spectroscopy (fNIRS) | -4.6 ± 4.9 | 32.3 ± 44.9 |
Flicker light-induced dilation of the retinal vessels (percentage increase over baseline diameter) will be measured in the right or left eye of each study participant using the Dynamic Vessel Analyzer (DVA, IMEDOS Systems, Jena, Germany). The change in retinal vessel diameters is tracked and reported as a %change from baseline, before and after treatment.
No measurements were reported for this outcome.
Transcranial Doppler sonography will be used to measure the change in the blood flow velocities during the cognitive n-back task between before and after treatment.
No measurements were reported for this outcome.
Changes in microvascular endothelial function will be assessed using laser speckle contrast imaging (LSCI) in the hand using the flow mediated dilation approach. The change in skin perfusion is calculated and reported as a fold change from baseline.
| fold change from baseline | Baseline | Endpoint |
|---|---|---|
| Microvascular Endothelial Function | 3.36 (1.83 to 4.03) | 3.19 (1.68 to 5.62) |
Changes in macrovascular endothelial function will be assessed using sonography during flow mediated dilation approach. The change in brachial artery diameter is calculated and reported as a %change from baseline.
| %change from baseline | Baseline | Endpoint |
|---|---|---|
| Macrovascular Endothelial Function | 8.20 (4.15 to 15.02) | 4.96 (2.61 to 9.91) |
Transcutaneous deep tissue oxygen saturation will be measured using the inSpectra near infrared device. The data are calculated and reported as a %change from baseline.
No measurements were reported for this outcome.
The arterial stiffness will be measured using the pulse wave analysis approach (SphygmoCor, Atcor medical, Itasca IL, or similar). Analysis generated the augmentation index which will be used for comparison before and after treatment.
No measurements were reported for this outcome.
ECG will be recorded for heart rate variability analysis. The values of high frequency domain, low frequency domain, their ratio, as well as total power will be calculated and used for comparison before and after treatment.
No measurements were reported for this outcome.
Video recordings of the sublingual vasculature will be performed using the high definition video camera GlycoCheck (Microvascular health solutions). Data collected will include perfused boundary region (um), and will be used for comparison before and after treatment.
No measurements were reported for this outcome.
Video recordings of the sublingual vasculature will be performed using the high definition video camera GlycoCheck (Microvascular health solutions). Data collected will include capillary density (mm/mm\^2), and will be used for comparison before and after treatment.
No measurements were reported for this outcome.
Video recordings of the sublingual vasculature will be performed using the high definition video camera GlycoCheck (Microvascular health solutions). Data collected will include red blood cell velocity (um/sec), and will be used for comparison before and after treatment.
No measurements were reported for this outcome.
Flanker Inhibitory Control and Attention Test was used to assess inhibitory control and attention. The participant is asked to focus on a particular stimulus while inhibiting attention to the stimuli flanking it. Scores are fully adjusted to nationally representative normative sample of NIH toolbox test takers, accounting for age, sex, race, and education (mean = 50; SD = 10). Higher scores represent better outcomes.
| T score | Baseline | Endpoint |
|---|---|---|
| Inhibitory Control and Attention | 44 (36 to 61) | 50 (42 to 57) |
Picture Sequence Memory Test was used to assess episodic memory. Participants are shown a number of activities, and then asked to reproduce the sequence of pictures as it was presented to them. Scores are fully adjusted to nationally representative normative sample of NIH toolbox test takers, accounting for age, sex, race, and education (mean = 50; SD = 10). Higher scores represent better outcomes.
| T score | Baseline | Endpoint |
|---|---|---|
| Episodic Memory | 56 (49 to 63) | 54 (45 to 58) |
List Sorting Working Memory Test was used to assess working memory. The participant is asked to recall and sequence different stimuli that are presented visually and via audio. Scores are fully adjusted to nationally representative normative sample of NIH toolbox test takers, accounting for age, sex, race, and education (mean = 50; SD = 10). Higher scores represent better outcomes.
| T score | Baseline | Endpoint |
|---|---|---|
| Working Memory | 55 (33 to 66) | 51 (40 to 70) |
Picture Vocabulary Test measures receptive vocabulary administered in a computer-adaptive test (CAT) format. Respondents select the picture that most closely matches the meaning of the word. Scores are fully adjusted to nationally representative normative sample of NIH toolbox test takers, accounting for age, sex, race, and education (mean = 50; SD = 10). Higher scores represent better outcomes.
| T score | Baseline | Endpoint |
|---|---|---|
| Language | 51 (44 to 63) | 51 (33 to 60) |
Dimensional Change Card Sort Test was used to assess cognitive flexibility and attention. The participant is asked to match a series of picture pairs to a target picture. Scores are fully adjusted to nationally representative normative sample of NIH toolbox test takers, accounting for age, sex, race, and education (mean = 50; SD = 10). Higher scores represent better outcomes.
| T score | Baseline | Endpoint |
|---|---|---|
| Executive Function | 63 (45 to 75) | 65 (45 to 81) |
Pattern Comparison Processing Speed Test was used to assess processing speed. Participants are asked to quickly determine whether two stimuli are the same or not the same. Scores are fully adjusted to nationally representative normative sample of NIH toolbox test takers, accounting for age, sex, race, and education (mean = 50; SD = 10). Higher scores represent better outcomes.
| T score | Baseline | Endpoint |
|---|---|---|
| Processing Speed | 53 (42 to 78) | 58 (44 to 72) |
Collected over From enrollment to 6 months. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Intervention | 0/11 (0%) | 0/11 (0%) | 0/11 (0%) |
| Age, Categorical(Participants) | Time Restricted Eating |
|---|---|
| <=18 years | 0 |
| Between 18 and 65 years | 10 |
| >=65 years | 1 |
| Sex: Female, Male(Participants) | Time Restricted Eating |
|---|---|
| Female | 10 |
| Male | 1 |
| Race (NIH/OMB)(Participants) | Time Restricted Eating |
|---|---|
| American Indian or Alaska Native | 0 |
| Asian | 2 |
| Native Hawaiian or Other Pacific Islander | 0 |
| Black or African American | 0 |
| White | 9 |
| More than one race | 0 |
| Unknown or Not Reported | 0 |
| Age, Continuous(Years) | Time Restricted Eating |
|---|---|
| Mean | 53.6 ± 8.0 |
| Ethnicity (NIH/OMB)(Participants) | Time Restricted Eating |
|---|---|
| Hispanic or Latino | 1 |
| Not Hispanic or Latino | 10 |
| Unknown or Not Reported | 0 |
| BMI(kg/m^2) | Time Restricted Eating |
|---|---|
| Mean | 30.3 ± 6.2 |
| Godin Leisure-Time Exercise Questionnaire(Participants) | Time Restricted Eating |
|---|---|
| Active | 9 |
| Insufficiently Active/Sedentary | 2 |
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University of Oklahoma