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Long-term Caloric Restriction and Cellular Aging Markers (CRONA)

This study has been completed.
Robert Wood Johnson Foundation
Information provided by (Responsible Party):
University of California, San Francisco Identifier:
First received: December 2, 2010
Last updated: September 20, 2011
Last verified: September 2011
The purpose of this study is to see whether people who have restricted the number of calories they eat for a long period of time, compared to normal-eating and obese people, have markers of cellular aging that look younger.


Study Type: Observational
Study Design: Observational Model: Cohort
Time Perspective: Cross-Sectional
Official Title: Caloric Restriction With Optimal Nutrition and Aging Study

Further study details as provided by University of California, San Francisco:

Primary Outcome Measures:
  • Telomere length [ Time Frame: One day ]
    This study is not a clinical trial, but the UCSF Committee on Human Research requires registration with It is a ONE TIME POINT study, where we get a simple blood draw from people from three groups - calorie restricting, normal eating, and obese. Therefore, there IS NO FOLLOW UP/time frame. The outcome measure is assessed on the day of the study. Telomere length is a marker of cellular aging and is used to understand how the cells are aging. We will investigate whether long-term caloric restriction is associated cross-sectionally with longer telomere length (less aging).

Biospecimen Retention:   Samples With DNA
Whole blood, serum.

Estimated Enrollment: 75
Study Start Date: December 2010
Calorie Restricting Group
Normal-eating controls
Obese comparison group


Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Sampling Method:   Non-Probability Sample
Study Population
Community sample and Calorie Restriction Society

Inclusion Criteria:

  • Calorie restricting group: Self-reported caloric restriction for at least two years
  • Calorie restriction group: BMI below 23
  • Normal eating control: Normal eating (no history of caloric restriction) for two years
  • Normal eating control: BMI below 30
  • Obese comparison group: BMI above 30
  • Obese comparison group: Normal eating (no history of caloric restriction) for two years

Exclusion Criteria:

  • Regular smoker for the past six months
  Contacts and Locations
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Please refer to this study by its identifier: NCT01256840

United States, California
University of California
San Francisco, California, United States, 94118
Sponsors and Collaborators
University of California, San Francisco
Robert Wood Johnson Foundation
Principal Investigator: A. Janet Tomiyama, Ph.D. University of California, San Francisco
  More Information

Responsible Party: University of California, San Francisco Identifier: NCT01256840     History of Changes
Other Study ID Numbers: UCSF-CHR-10-01323
Study First Received: December 2, 2010
Last Updated: September 20, 2011 processed this record on August 18, 2017