Optimization of Chrononutrition to Reduce the Risk of Disease in Shift Workers

Inclusion criteria

• Age: 18-70 years
• BMI ≥ 25 kg/m2 (or ≥ 23 kg/m2 for Asian adults)
• Own a smartphone (Apple iOS or Android OS)
• Baseline eating window ≥ 14 h/day
• Night shift nurses and nursing assistants who are working a 12-hour night shift at least 3 days/week.
• Have been doing night shift work for at least 3 months.
• Patients on cardiovascular medications (HMG CoA reductase inhibitors (statins), metformin, lipid-modifying drugs (including over-the-counter drugs such as red yeast rice and fish oil), anti-hypertensive, drugs), are allowed
• If patients have Type 2 Diabetes, they will be included in the study if A1c is less than 9 and they are not on insulin.

Exclusion criteria

• Insufficient dietary logging on the mCC app is defined as less than 7 of 14 days of baseline of dietary logging with a minimum of 2 items a day, at least 5 hours apart.
• Type 1 Diabetes or Insulin-dependent Type 2 Diabetes.
• Use of sulfonylurea or insulin within the last 3 months (due to unknown safety with TRE)
• Use of medications that are known to cause weight loss such as SGLT2 inhibitors and GLP1 receptor agonists)
• BMI \> 50 kg/m2
• Change in medications that could impact study outcomes within the past 3 months
• Change in weight of \>4kg in the past 3 months
• Women who are pregnant, breastfeeding, or are trying to become pregnant during the study period. If a participant becomes pregnant during the study, they will be excluded from continuing the study.
• Systolic BP greater than 160 mmHg and/or diastolic BP greater than 110 mmHg at rest
• Fasting LDL cholesterol greater than 250 mg/dL
• Fasting triglycerides greater than 500g/dL
• Active tobacco abuse or illicit drug use or history of treatment for alcohol abuse in the past 5 years.
• Frequent (more than 4) travel involving a time zone change of more than 3 hours over the 1-year study period
• Prolonged leave from work (a continuous month or longer) during the study
• Active treatment for inflammatory and/or rheumatologic disease
• History of a major adverse cardiovascular event within the past year (acute coronary syndrome, percutaneous coronary intervention, coronary artery bypass graft surgery, hospitalization for congestive heart failure, stroke/transient ischemic attack)
• Uncontrolled arrhythmia (i.e. rate-controlled atrial fibrillation/atrial flutter are acceptable)
• History of thyroid disease requiring dose titration of thyroid replacement medication(s) within the past 3 months (hypothyroidism on a stable dose of thyroid replacement therapy is allowed).
• History of adrenal disease in the past 5 years
• History of malignancy undergoing active treatment, except non-melanoma skin cancer, in the past 5 years
• History of an eating disorder in the past 5 years
• History of cirrhosis in the past 5 years
• History of stage 4 or 5 chronic kidney disease or dialysis in the past 5 years
• History of HIV/AIDs
• Currently enrolled in weight-loss or weight-management program
• History of surgical intervention for weight management within the past 2 years, or longer if deemed unsafe following review by medical investigators
• Uncontrolled psychiatric disorder including prior hospitalization