Oral Glutathione Supplementation on the Levels of Blood Glutathione

This study is ongoing, but not recruiting participants.
Information provided by (Responsible Party):
John P. Richie, Milton S. Hershey Medical Center
ClinicalTrials.gov Identifier:
First received: January 6, 2010
Last updated: September 15, 2014
Last verified: September 2014
This trial is designed to provide evidence of the efficacy of glutathione supplementation and health(GSH) and includes the assessment of both short term and long term effects. Based on previous laboratory animal studies and clinical data, the investigators anticipate that the effects of oral GSH supplementation will be progressive and cumulative. The study will also allow for the evaluation of effects of withdrawal of the supplement on the outcome variables.

Condition Intervention
Healthy Adults
Drug: Glutathione supplementation
Other: Placebo

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Open Label
Primary Purpose: Basic Science
Official Title: Effect of Oral Glutathione Supplementation on the Levels of Blood Glutathione and Markers of Oxidative Stress in Healthy Adults (Glutathione Supplementation and Health (GSH) Study)

Resource links provided by NLM:

Further study details as provided by Milton S. Hershey Medical Center:

Primary Outcome Measures:
  • Evaluation of the effect of glutathione on key biomarkers [ Time Frame: 6 to 7 months ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • Evaluations will be carried out to expand the above comparison by including adjustments for potential prognostic factors. [ Time Frame: 6 to 7 months ] [ Designated as safety issue: No ]

Enrollment: 61
Study Start Date: February 2010
Estimated Study Completion Date: June 2015
Primary Completion Date: July 2011 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Group A
Drug: Glutathione supplementation
500 mg, two times daily
Other Names:
  • Gluthathione Peroxidates
  • GSH
Experimental: Group B
Drug: Glutathione supplementation
125 mg, two times daily
Other Names:
  • Gluthathione peroxidases
  • GSH
Placebo Comparator: Group C
Other: Placebo
2 times daily
Other Names:
  • Gluthathione peroxidases
  • GSH

Detailed Description:

This is a randomized double-blind, placebo-controlled study in which the treatment allocations will be kept sealed until the final statistical evaluation. The design will include the recruitment of 60 healthy subjects (30-79 yr of age) randomized into 3 groups. A total of 48 subjects, 16 per group will be required based upon power calculations and results from a previous clinical trial with selenium. An additional 4 subjects per group will be placed on trial to account for possible attrition or non-compliance. Blood, urine and exfoliated buccal mucosal samples will be obtained from all subjects at baseline. Questionnaire data on usual dietary intake will also be obtained at baseline. Eligible subjects will be required to have not have taken any high dose antioxidant supplements for at least 1 month prior to the study. Subjects will then begin supplementation according to the following schedule:

Group A, GSH (500 mg, 2 times daily); Group B, GSH (125 mg, 2 times daily); Group C, placebo (2 times daily). Eligible participants who sign the informed consent will be randomly assigned to either placebo or high or low dose Glutathione groups. Participants will be asked not to consume any other high-dose vitamin, multi-vitamin, or mineral supplements containing glutathione throughout the study in order to prevent variation in dose of supplemental GSH between subjects. Supplementation will continue for 6 months with biological samples collected at 1, 3 and 6 months after baseline. At 6 months, supplementation will be discontinued. A final collection of biological samples will occur 1 month afterwards. Compliance will be monitored by pill count.

Levels of glutathione will be measured in plasma, lymphocytes, and red blood cells as well as in exfoliated buccal mucosal cells. Biomarkers of oxidative stress will include blood levels of glutathionylated proteins and 8-isoprostanes and urine levels of 8-hydroxydeoxyguanosine. Glutamylcystine ligase and GST activities, and C-reactive protein will be determined in blood. Immune function biomarkers will be analyzed including t-natural killer cell cytotoxicity, lymphoproliferation, neutrophils phagocytosis, neutrophil respiratory burst assays.


Ages Eligible for Study:   30 Years to 79 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Healthy male and females between the ages of 30 and 79 years of age
  • Not taking glutathione as a dietary supplement
  • Not taking high dose antioxidant supplement prior to 1 month
  • Baseline blood glutathione level of < 1 mmol/L

Exclusion Criteria:

  • History or evidence of disease including cancer, diabetes, heart disease
  • Subjects who smoke
  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: NCT01044277

United States, Pennsylvania
Penn State Milton S. Hershey Medical Center
Hershey, Pennsylvania, United States, 17033
Sponsors and Collaborators
Milton S. Hershey Medical Center
Principal Investigator: John P. Richie, Ph.D. Milton S. Hershey Medical Center
  More Information

Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: John P. Richie, Professor of Public Health Sciences and Pharmacology, Milton S. Hershey Medical Center
ClinicalTrials.gov Identifier: NCT01044277     History of Changes
Other Study ID Numbers: PSHCI 09-059 
Study First Received: January 6, 2010
Last Updated: September 15, 2014
Health Authority: United States: Institutional Review Board

Keywords provided by Milton S. Hershey Medical Center:
gluthathione peroxidases

ClinicalTrials.gov processed this record on May 26, 2016