for people ages 21-65 (full criteria)
Healthy Volunteers
healthy people welcome
at La Jolla, California
study started
estimated completion
Principal Investigator
by Pam Taub, MD
Photo of Pam Taub
Pam Taub



This is the first study of its kind to assess and test an intervention to improve biological rhythms and general health of shift workers, specifically first responders with San Diego Fire and Rescue. In a randomized control trial, investigators intend to measure the health impact of Time Restricted Eating in emergency responders who work a 24-hour shift schedule.

Official Title

Optimizing Circadian Rhythms by Regulating Eating Patterns to Reduce Cardiometabolic Disease Risk Among Firefighters--The Healthy Heroes Study


Participants will be randomly assigned to a control group of behavioral nutrition counseling (standard of care) or the intervention group of standard of care with the addition of adopting a 10 hour eating window for one year (TRE). For the first 3 months of intervention, participants will be monitored closely by the research team. For the following 9 months, participants will be in a self-monitored intervention period. Investigators will evaluate the impact of TRE on blood glucose levels, biomarkers, sleep/mood, and weight loss. These assessments will be made at baseline, at the end of the 12-week monitored intervention period, and every 3 months (months 6, 9, and 12) during the self-monitored intervention period for one year. Food/drink intake, activity, and sleep will be monitored with the smartphone myCircadianClock application ("mCC app") throughout the study. A continuous glucose monitor, a wrist-worn actigraphy device, and questionnaires will also be used during the study.


Shift Workers' Health Time Restricted Eating Fasting Firefighters San Diego Fire and Rescue Cardiometabolic Health First Responder Shift Workers Time-Restricted Eating


For people ages 21-65

As per recommendations from the fire department, fire department unions, and funding agencies, we did not require compromised health measures (e.g. hyperglycemia, hypertension, etc.) as inclusion criteria for they would be discriminatory against some firefighters.

Inclusion Criteria:

  • Firefighter or work a 24-hr shift schedule with San Diego Fire and Rescue
  • Age: 21-65 years
  • Own a smartphone (Apple or Android Operating System)
  • If participants are on cardiovascular medications (HMG-CoA reductase inhibitors (statins), other lipid modifying drugs (including over the counter drugs such as red yeast rice and fish oil), anti-hypertensive, anti-diabetes drugs), no dose adjustments will be allowed during the study period

Exclusion Criteria:

  • Insulin-dependent diabetes mellitus
  • Presence of acute chronic inflammatory or autoimmune disease (defined by acute symptoms or C-reactive protein >10 mg/L), malabsorption syndromes, liver disease, or kidney disease (stage 3 or greater)
  • Uncontrolled thyroid disease
  • Intake of drugs likely to interfere with study endpoints, including corticosteroids, anabolic steroids, anti-psychotics, antiretroviral drugs, and immunosuppressive drugs (within 3 months of starting the study)
  • Presence or recent history of anemia (hematocrit <33% within 3 months of starting the study)
  • History of bariatric surgery
  • Pregnant or breast-feeding women
  • Current or recent (within 12 months of starting the study) pregnancy or breastfeeding, or intention of becoming pregnant in the next 6 months
  • Any cancer other than non-melanoma skin cancer in the last 3 years
  • On a special or prescribed diet for other reasons (e.g. Celiac disease)
  • Depression determined by the Beck Depression Inventory (BDI)
  • Planned international travel during study period
  • Insufficient logging on the mCC app (does not log at least 2 entries a day for 10 of 14 days) during baseline will exclude from being randomized into the intervention period


  • University of California, San Diego
    La Jolla California 92093 United States

Lead Scientist at UCSD

  • Pam Taub, MD
    Pam R. Taub, MD, FACC, FASPC is an Associate Professor at the UC San Diego School of Medicine in the Department of Cardiovascular Medicine. She is the Founding Director of the Step Family Foundation Cardiac Rehabilitation and Wellness Center. Dr. Taub was responsible for all aspects of creating the center.


in progress, not accepting new patients
Start Date
Completion Date
University of California, San Diego
Study Type
Last Updated