Obesity, Inflammation and Oxidative Stress

The recruitment status of this study is unknown because the information has not been verified recently.
Verified June 2011 by University of California, Berkeley.
Recruitment status was  Recruiting
Kaiser Permanente
Information provided by:
University of California, Berkeley
ClinicalTrials.gov Identifier:
First received: December 8, 2009
Last updated: June 16, 2011
Last verified: June 2011

The purpose of this study is to determine whether or not Vitamin C (1000 mg/day) can reduce markers of inflammation, especially C-reactive protein (CRP), in obese persons with baseline CRP greater than 1 mg/dl.

Condition Intervention Phase
C-reactive Protein
Oxidative Stress
Dietary Supplement: Vitamin C (ascorbic acid)
Phase 3

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor)
Primary Purpose: Prevention
Official Title: Obesity, Inflammation and Oxidative Stress

Resource links provided by NLM:

Further study details as provided by University of California, Berkeley:

Primary Outcome Measures:
  • high-sensitivity C-reactive protein [ Time Frame: After 8 weeks of intervention ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • CRP-related markers of inflammation and oxidative stress, including cytokines and F2-isoprostanes. [ Time Frame: After 8 weeks of intervention. ] [ Designated as safety issue: No ]

Estimated Enrollment: 552
Study Start Date: January 2010
Estimated Study Completion Date: July 2012
Estimated Primary Completion Date: July 2012 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Placebo Comparator: Placebo
Two tablets, daily, for 8 weeks
Dietary Supplement: Vitamin C (ascorbic acid)
1000 mg/day (two 500-mg tablets), 8 weeks
Experimental: Vitamin C Dietary Supplement: Vitamin C (ascorbic acid)
1000 mg/day (two 500-mg tablets), 8 weeks

Detailed Description:

The long-term objective of this project is to identify nutritional factors that can reduce the inflammatory component of obesity. Therapies to minimize obesity-related comorbidities are needed, and targeting inflammation may help slow the progression of obesity towards cardiovascular disease and insulin resistance.

Adipose tissue is a source of inflammatory cytokines, and obesity is now viewed as a chronic, low-grade inflammatory state. Inflammation itself is a contributor to the chronic diseases associated with obesity. C-reactive protein (CRP) is a key marker of inflammation, and as a downstream marker it provides functional integration of upstream cytokine activation associated with inflammation. We have previously shown that vitamin C, but not vitamin E, reduces CRP in active and passive smokers and in nonsmokers. The reduction is seen primarily in persons with CRP ≥1.0 mg/L, the CDC threshold for elevated cardiovascular disease risk. We also found that 75% of obese nonsmokers had CRP ≥1.0 mg/L.

The important observation of reduction in elevated CRP by vitamin C now needs to be confirmed in a rigorous study with adequate sample size, to permit justifiable conclusions about the potential usefulness of this agent in reducing inflammation in the obese. We will conduct a placebo-controlled, randomized trial in 552 healthy obese individuals with moderate CRP elevations (CRP ≥1.0 mg/L). Participants will be randomized to either 1000 mg/day vitamin C or placebo for a period of 2 months. We will also characterize the pathways through which this effect takes place by measuring cytokines and oxidative stress.

This project is important because if our previous finding is confirmed in this population, it could offer a low-cost alternative to use of statins to reduce inflammation in persons without other risk factors.


Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • BMI ≥ 30
  • hsCRP ≥ 1 mg/L
  • Age 18+
  • Member of Kaiser Permanente Health Plan of Northern California

Exclusion Criteria:

  • Smoker
  • Unwilling to discontinue vitamin supplements for study duration
  • Unwilling/unable to use acetaminophen in place of OTC anti-inflammatory medications
  • Use of certain medications
  • History of certain medical conditions
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01028976

Contact: Christopher D. Jensen, PhD 510-891-3665 Christopher.D.Jensen@nsmtp.kp.org
Contact: Eva R. Greenstein 510-891-5918 Eva.R.Greenstein@kp.org

United States, California
Kaiser Permanente of Northern California, Division of Research Recruiting
Oakland, California, United States, 94612
Contact: Jensen         
Contact: Greenstein         
Principal Investigator: Douglas Corley, MD, PhD         
Sponsors and Collaborators
University of California, Berkeley
Kaiser Permanente
Principal Investigator: Gladys Block, PhD University of California, Berkeley
  More Information

Responsible Party: Gladys Block, University of California, Berkeley
ClinicalTrials.gov Identifier: NCT01028976     History of Changes
Other Study ID Numbers: DK062378-05
Study First Received: December 8, 2009
Last Updated: June 16, 2011
Health Authority: United States: Institutional Review Board

Keywords provided by University of California, Berkeley:
randomized controlled trial
primary prevention
Vitamin C
C-reactive protein
anti-inflammatory agents

Additional relevant MeSH terms:
Pathologic Processes

ClinicalTrials.gov processed this record on March 25, 2015