Daily Eating Patterns for Total Health Study
NCT Number: NCT06455995
Acronym: DEPTH
Status: RECRUITING
Study Type: INTERVENTIONAL
Phases: NA
Conditions: Obesity
Interventions: BEHAVIORAL: DEPTH|BEHAVIORAL: DEPTH-Morning|BEHAVIORAL: DEPTH-Evening
Sponsor: The University of Tennessee, Knoxville
Sex: ALL
Age: ADULT
Enrollment: 174
Study Design: Allocation: RANDOMIZED|Intervention Model: PARALLEL|Masking: SINGLE (OUTCOMES_ASSESSOR)|Primary Purpose: TREATMENT
Start Date: 2024-07-16
Completion Date: 2028-12
Locations: Healthy Eating and Activity Laboratory, Knoxville, Tennessee, 37996, United States

Summary:
The goal of this randomized controlled trial is to learn how the time of day when calories are eaten affects weight loss in the long-term (12 months). The main aims are to learn:

1. The influence of time-based energy intake goals on longer-term weight loss.
2. The influence of time-based energy intake goals on eating temporal patterns, sleep regularity, and appetite regulation.

Researchers will compare whether goals to eat most of a person's calories in the morning or evening work to treat obesity.

Participants will:

1. Eat a reduced-calorie, low-fat diet (some participants will have goals to eat their calories at certain times of day based on their group)
2. Be physically active at least 200 minutes
3. Receive a cognitive behavioral intervention

Primary Outcome Measures: Percent Weight Change, Percent change in weight (weight change in lbs at follow up / baseline weight in lbs), 0, 3, 6, and 12 months|Body Mass Index (BMI), Change in BMI calculated as weight in kg / height in m2, 0, 3, 6, and 12 months
Secondary Outcome Measures: Dietary intake, Dietary intake will be assessed by 3 (2 weekdays and 1 weekend day), random, 24-hr dietary phone recalls, using the five-step, multiple-pass method, 0, 3, 6, and 12 months|Sleep, Hours of daily sleep objectively measured by accelerometry, 0, 3, 6, and 12 months|Appetite regulation, Time- and semi-random sampling will be initiated via a smartphone tone, prompting participants to complete ratings (i.e. hunger, fullness, temptation to eat, desire to eat, and control over eating), using 100 mm visual analogue scales, 0, 3, 6, and 12 months|Waist circumference, Change in waist circumference in inches, 0, 3, 6, and 12 months|Moderate- to vigorous-physical activity (MVPA), Time in MVPA objectively measured by accelerometry, 0, 3, 6, and 12 months|Chronotype, An individuals' circadian state (phase relationship between the circadian system of an individual and the zeitgeber cycle) measured via the shortened version of the Munich ChronoType Questionnaire, 0, 3, 6, and 12 months
Other Outcome Measures: Process evaluation: Self-monitoring of diet, Achievement of condition specific diet goals (adherence) will be documented (days/wk for overall energy and fat goal \[staying with + 5% of each goal\]; first eating occasion \< 60 minutes of awakening; daily eating window length \< 12 hours; four eating occasions per day; and time-based energy intake goals \[staying within + 5% of each goal\] for Morning and Evening only), Throughout the 12-month intervention|Process evaluation: Self-monitoring of physical activity, From physical activity self-monitoring records, number of weeks minutes that MVPA is within + 5% of the goal will be documented., Throughout the 12-month intervention|Process evaluation: Attendance, Number of sessions attended will be recorded, Throughout the 12-month intervention|Process evaluation: Fidelity, All sessions will be audiotaped and the PI will review 33% of these sessions for treatment fidelity, Throughout the 12-month intervention