TREAT for Metabolic Health

Inclusion Criteria:

- BMI ≥25 and ≤35kg/m2;

- prediabetes (ADA criteria 2019) or T2D diet-controlled, and/or treated with metformin only, with HbA1C ≤7%;

- controlled BP on stable regimen or stage 1 hypertension 130-139/80-89mmHg, meeting AHA hypertension clinical practice guidelines for lifestyle intervention;

- on stable regimen for dyslipidemia or triglycerides <300 mg/dl;

- in possession of a smart phone;

- with habitual wake up time after 5AM, average bed time between 21:30 and 24:00 and with average hours of sleep ≥6h;

- who habitually eat breakfast;

- with weight stability within 5% of screening for the last 3 months;

- sedentary to moderately active (<7500 steps/d);

- English speaking (the App has not yet been translated in Spanish).

Exclusion Criteria:

- sleep disorder, e.g. known obstructive sleep apnea [OSA] on CPAP, severe OSA with apnea-hypopnea index >30 events/h, significant daytime symptoms of OSA identified at screening with the Epworth Sleepiness Scale score >10, periodic limb movements of sleep, narcolepsy, current shift work or in last 6-mo, travel more than 1 time zone during intervention); severe insomnia with score ≥15 on Insomnia Severity Index;

- significant organ system dysfunction/disease: severe pulmonary, kidney or cardiovascular disease; evidence of active illness (e.g., fever);

- history of seizure disorder;

- previous bariatric surgery or on weight loss medication;

- history of or current significant food intake or psychiatric disorder (e.g., prior or current diagnosis, current Beck depression inventory (BDI-II)>13; Beck anxiety inventory (BAI)>10);

- use of dietary supplements and/or medications known to affect sleep, circadian rhythms or metabolic function;

- smoking tobacco or using illegal or recreational drugs;

- consume excessive alcohol (women: >14 drinks/wk; men: >21 drinks/wk);

- consume large amounts of caffeine daily (>2 cups of coffee or 8 oz caffeinated drinks per day);

- participate in intense exercise (causing heavy breathing and sweating, such as jogging) >2 d/wk for ≥35 min or moderate exercise (e.g., brisk walking) for >150 min/wk;

- anemia and/or blood donation in 2-mo prior to inpatient studies;

- have conditions that render individual unable to complete all testing procedures [e.g., unable to stay overnight or frequent travel across ≥ 1 time zones];

- extreme early and late chronotype;

- food allergies;

- unwilling/unable to provide informed consent.