Ramaley N368B
Department of Integrative Physiology
University of Colorado
Boulder, CO 80309-0354
Office Phone: 303-735-7377
Fax: 303-492-0811

Research Interests

We use large, observational data sets to query associations of circadian phenotypes, circadian misalignment, sleep, and work hours with health and longevity (with an emphasis on type 2 diabetes, cardiovascular disease and depression). Our work aims to identify modifiable risk factors in the realm of circadian and sleep research that can be leveraged for prevention strategies in real life settings.

Current interests include:

  1. Cardio-metabolic consequences of circadian misalignment and sleep deprivation
  2. Work hour characteristics, occupational safety, and tolerance to shift work
  3. Effects of sleep, and the mismatch between chronotype and work hours on mood and depression
  4. Quantification of light exposure in real life 
  5. Circadian phenotyping

See our detailed Circadian Rhythm and Sleep Epidemiology Lab website for the most up-to-date information about current research and other happenings in the lab.


  • DirectorDr. Céline Vetter
  • Post-doctoral Fellow: Dr. Josef Fritz
  • Professional Research Assistant: Sarah Haydu, M.A.
  • Graduate Students: Akram Imam, Larissa Hunt, Jeremie Kautzmann (BS/MS program)
  • Undergraduate Students: Katherine Buhl, Beau Bentley, Kaitlin Buck
  • Collaborators: Richa Saxena, Ph.D., Jacqueline Lane, Ph.D., and Hassan Dashti, Ph.D., Massachusetts General Hospital, Center for Medical Genomics, Harvard Medical School/Broad Institute of MIT and Harvard; Frank Scheer, Ph.D., Harvard Medical School; Martin Rutter, M.D., University of Manchester, UK; Andrew J.K. Phillips, Ph.D., Monash University, Australia; Eva Schernhammer, M.D., Ph.D., Channing Division of Network Medicine, Brigham and Women’s Hospital, and Medical University of Vienna, Austria; Kyriaki Papantoniou, M.D., Ph.D., Medical University of Vienna, Austria; Linda van Kerkhof, Ph.D., Centre for Health Protection, National Institute for Public Health and the Environment, Bilthoven, The Netherlands; Sanjay Patel, M.D., M.S., University of Pittsburgh Medical Campus Sleep Laboratory, Pittsburgh, PA; Phyllis Zee, M.D., Ph.D. and Kathryn Reid, Ph.D., Northwestern Feinberg School of Medicine, and Center for Sleep and Circadian Biology, Northwestern University; Till Roenneberg, Ph.D. and Eva Winnebeck, Ph.D., Institute of Medical Psychology, Ludwig-Maximilian-University, Munich, Germany; Sylvia Rabstein, Ph.D. and Katarzyna Gawrych, Ph.D., Institut für Prävention und Arbeitsmedizin der Deutschen Gesetzlichen Unfallversicherung, Ruhr Universität Bochum, Germany.

Current Research Projects

  • Sleep and cardio-metabolic health in the Hispanic Community Health Study (HCHS)/SOL
  • Contemporary shift schedules and its association with sleep patterns and circadian strain in Nurses' Health Study 3
  • Light and health in the Hispanic Community Health Study (HCHS)/SOL
  • Sleep and shift work in relation to cardio-metabolic health in UK Biobank

Opportunities for Undergraduates

Undergraduates who seek research experience in human circadian and sleep epidemiology must have:

  • Either completed or be currently enrolled in IPHY 2800 (Introductory Statistics)
  • An interest in using epidemiological and statistical tools to study health
  • Enroll in Independent Study (i.e. IPHY 4860) for 8-10 hours/week for at least one semester.

For more information, contact Prof. Céline Vetter (celine.vetter@colorado.edu).

Recent Publications

  • Vetter, C. Circadian Disruption: What do we actually mean? European Journal of Neuroscience. https://doi.org/10.1111/ejn.14255
  • Vetter C, Chang SC, Devore EE, Rohrer F, Okereke OI, Schernhammer ES. Prospective study of chronotype and incident depression among middle- and older-aged women in the Nurses' Health Study II. Journal of Psychiatric Research 103: 156-160, 2018.
  • VoPham T, Weaver MD, Vetter C, Hart JE, Tamimi RE, Laden F, Bertrand KA. Circadian misalignment and hepatocellular carcinoma incidence in the United States. Cancer Epidemiology, Biomarkers & Prevention doi: 10.1158/1055-9965.EPI-17-1052, 2018.
  • Vetter C, Dashti HS, Lane JM, Anderson SG, Schernhammer ES, Rutter MK, Saxena R, Scheer FAJL. Night Shift Work, Genetic Risk, and Type 2 Diabetes in the UK Biobank. Diabetes Care pii: dc171933, 2018.
  • Huang T, Poole EM, Vetter C, Rexrode KM, Kubzansky LD, Schernhammer E, Rohleder N, Hu FB, Redline S, Tworoger SS. Habitual sleep quality and diurnal rhythms of salivary cortisol and dehydroepiandrosterone in postmenopausal women. Psychoneuroendocrinology 84: 172-180, 2017.
  • Keller LK, Grünewald B, Vetter C, Roenneberg T, Schulte-Körne G. Not later, but longer: sleep, chronotype and light exposure in adolescents with remitted depression compared to healthy controls. European Child Adolescent Psychiatry Mar 29, 2017.
  • Vetter C, Scheer FAJL. Circadian Biology: Uncoupling Human Body Clocks by Food Timing. Dispatch. Current Biology 27: R656-658, 2017.
  • von Schnurbein J, Boettcher C, Brandt S, Karges B, Dunstheimer D, Galler A , Denzer C, Denzer F, Vollbach H, Wabitsch M, Roenneberg T, Vetter C. Sleep and glycemic control in adolescents with type 1 diabetes. Pediatric Diabetes 0: 17, 2017.
  • Fischer D, Vetter C, Oberlinner C, Wegener S, Roenneberg T. A unique, fast-forwards rotating schedule with 12-h long shifts prevents chronic sleep debt. Chronobiology International 33: 98-107, 2016.
  • Fischer D, Vetter C, Roenneberg T. A novel method to visualise and quantify circadian misalignment. Scientific Reports 6: 38601, 2016.
  • van de Ven HA, van der Klink JJ, Vetter C, Roenneberg T, Gordijn M, Koolhaas W, de Looze MP, Brouwer S, Bültmann U. Sleep and need for recovery in shift workers: do chronotype and age matter? Ergonomics 59: 310-24, 2016.
  • Vetter C, Devore EE, Wegrzyn LR, Massa J, Speizer FE, Kawachi I, Rosner B, Stampfer MJ, Schernhammer ES. Association Between Rotating Night Shift Work and Risk of Coronary Heart Disease Among Women. Journal of the American Medical Association 315: 1726-34, 2016.
  • Yong M, Fischer D, Germann C, Lang S, Vetter C, Oberlinner C. Are chronotype, social jetlag and sleep duration associated with health measured by Work Ability Index? Chronobiology International 33: 721-9, 2016.