Dinner Time for Obesity and Prediabetes

Exclusion Criteria

• •Sleep disorder including insomnia, untreated moderate-severe sleep apnea, restless leg syndrome, or narcolepsy
• •Night shift work
• •Extreme delayed sleep phase defined as self-reported routine bedtime later than 1:00 AM or having mid-sleep on free days later than 5:00 AM on the Munich Chronotype Questionnaire (MCTQ) or DLMO later than 24:00
• •Gastroesophageal reflux disease that affects ability to tolerate a dinner close to bedtime
• •Active smoking
• •Current drug or alcohol use or dependence that, in the opinion of the site investigator, would interfere with adherence to study requirements.
• •Diabetes (type 1 or 2) or on any diabetes medications besides metformin
• •Evidence of metabolic or cardiovascular disease, or disease that may influence metabolism (e.g. cancer, thyroid disease)
• •Hemoglobin A1c ≥5.7% for NWH cohort; Hemoglobin A1c ≥6.5% for OPD cohort
• •Hemoglobin \< 10 g/dL
• •Self-reported kidney disease
• •Any known history of an inherited metabolic disorder
• •Pregnant or lactating female (pregnancy test will be required prior to metabolic visits)
• •Peri-menopausal or post-menopausal female as determined by follicle stimulating hormone of \> 30 mIU/mL or fewer than 3 menstrual periods in 6 months
• •Professional or collegiate athlete
• •Participants who have travelled across time zones must have adequate time to recover from jet lag prior to enrollment (i.e., at least 3 days per time zone). Travel across \>1 time zone after enrollment in the study will not be permitted.
• •Weight less than 40 kg or more than 180 kg
• •Gastrointestinal disorders that can lead to obstruction of the digestive tract (i.e. diverticular disease, history of bowel obstruction, inflammatory bowel disease, motility disorder)
• •History of any surgical procedures in the gastrointestinal tract.
• •Swallowing disorders
• •Taking any prescription medication or other drug that may influence metabolism (e.g. diet/weight-loss medication, asthma medication, blood pressure medication, psychiatric medications, corticosteroids, or other medications at the discretion of the PI and/or study team)
• •Chronic use of sedative hypnotics, anxiolytics, opiates
• •Use of medications that can affect circadian rhythm (beta blockers, melatonin)
• •Presence of a cardiac pacemaker or other implanted electro-medical devices
• •Those who have to undergo strong electromagnetic field during the period of use of the ingestible thermosensor (i.e. MRI)
• •Weight loss or gain of ≥ 5% of total body weight over the preceding 3 months
• •Currently participating in a weight loss program
• •Prior bariatric surgery
• •Volunteers with strict dietary concerns (e.g. vegetarian or kosher diet, food allergies)
• •History of significant intravenous access issues
• •Non-English speaking individuals: The complexity of the instructions for various components of the study would make the study procedures difficult to follow in the setting of a language barrier.
• •Other conditions or situations at the discretion of the PI