Time Restricted Eating for Metabolic and Psychological Optimization

Participants completed two assessments of learning and memory at each time point. The Hopkins Verbal Learning Test Revised (HVLT-R) was used to assess verbal memory and the Brief Visual Memory Test - Revised (BVMT-R) was used to assess visual memory. Both the HVLT-R and the BVMT-R provide three separate scores that reflect total learning, retention of information, and recognition of learned items following a delay. In order to create a single Memory performance score, each of these six scores were ranked at each time point and a mean rank was created, with higher scores reflecting higher Memory performance. The mean rank for Memory performance at 12 weeks was used as the outcome, controlling for baseline Memory performance. Larger mean ranks at 12 weeks indicate greater improvements. As a rank-based outcome, values have no fixed theoretical upper or lower bound.

Participants underwent multiple assessments of Executive Functioning at each time point. Specifically, participants completed the Trail Making Test Parts A & B, the Digit Span Forwards and Backwards Tasks, the Digit Symbol Substitution Test, the Controlled Oral Word Association Test, the Animal Naming Test, and the Stroop Word and Color-Word Interference Tests at both pre-and-post treatment. In order to create a single Executive Function score, each of these nine measures were ranked at each time point and a mean rank was created, with higher scores reflecting higher Executive Function performance. The mean rank for Executive Function performance at 12 weeks was used as the outcome, controlling for baseline Executive Function performance, with larger 12-week mean ranks indicating greater improvements compared to baseline. As a rank-based outcome, values have no fixed theoretical upper or lower bound.

Participants underwent assessments of multiple metabolic markers at each time point. Metabolic biomarkers included glucose, β-hydroxybutyrate, adiponectin, lactate, leptin, non-esterified fatty acids (NEFAs), and fibroblast growth factor-21. In order to create a single measure of Metabolic Function, each of these seven metabolic biomarkers were ranked at each time point and a mean rank was created, with higher scores reflecting better Metabolic Function. The mean rank for Metabolic Function at 12 weeks was used as the outcome, controlling for baseline Metabolic Function. If time restricted fasting was effective in improving Metabolic Function, then the mean rank composite score should be larger at 12 weeks compared to baseline. As a rank-based outcome,values have no fixed theoretical upper or lower bound.

Participants underwent assessments of multiple inflammatory markers at each time point. Inflammatory biomarkers included interleukin-6, high-sensitivity C-reactive protein, vascular cell adhesion molecule, intracellular adhesion molecule, interleukin-10, tumor necrosis factor-alpha, tumor necrosis factor receptor type I, and tumor necrosis factor receptor type II. In order to create a single measure of Inflammatory Function, each of these seven inflammatory biomarkers were ranked at each time point and a mean rank was created, with higher scores reflecting higher Inflammatory Function. The mean rank for Inflammatory Function at 12 weeks was used as the outcome, controlling for baseline Inflammatory Function. Smaller values at 12 weeks compared to baseline were indicative of reduced inflammation. As a rank-based outcome, values have no fixed theoretical upper or lower bound.