for people ages 18-65 (full criteria)
at San Diego, California
study started
estimated completion
Principal Investigator
by Ryan Bradley, ND, MPH
Photo of Ryan Bradley
Ryan Bradley



The purpose of this research study is to find out whether certain plant-based foods may be beneficial for individuals with type 2 diabetes. To meet the goal, study participants will be fed known amounts of foods and nutrients. Before and after participants have eaten the food, they will self-measure height, weight, and waist circumference and study staff will administer questionnaires. Blood samples will be taken at a local lab to measure blood sugar and blood lipids.All study appointments will be conducted online.

Official Title

Effects of the "Glutathione Support for Health (GSH)" Plan on Glutathione Status in Type 2 Diabetes


This research study is a randomized, controlled trial that will evaluate whether diet and nutrition education on, and short-term partial feeding of, specific plant foods high in the antioxidant glutathione will impact total glutathione status, gamma-glutamyltransferase (GGT) activity, glucose control or insulin sensitivity in people with type 2 diabetes. Dietary education will include information on plant sources of glutathione, as well as, cooking methods to reduce glycation and lipid peroxidation during cooking, which may indirectly alter glutathione status by reduce demand for elimination of these compounds. Participants will be randomized to one of two groups: the educational intervention plus partial feeding of two small meals per day vs. a wait list control group that will receive standard advice on nutrition for diabetes. After 12 weeks, the intervention group will no longer receive foods, but will be followed for 12 additional weeks to determine if lasting effects are achieved. After 12 weeks, the control group will receive access to the educational materials, but will not receive study foods, to see if the educational intervention alone impacts food/nutrition choices. Both groups will have lab measures (as described above) again after this additional 12 weeks, for a total duration of 24 weeks in the trial.


Type 2 Diabetes Glutathione Nutrition Diabetes Mellitus Diabetes Mellitus, Type 2 GSH Foods Nutrition education about glutathione sources in the diet


You can join if…

Open to people ages 18-65

  • Men and women
  • Ages 18 to 65
  • Type 2 diabetes
  • Free of self-reported acute and confounding chronic diseases (e.g., heart failure, kidney disease, liver disease, gastrointestinal disorder) based on a standardized medical history questionnaire
  • Free of alcoholism, smoking and major cardiovascular event with the past 6 months
  • Not on insulin to help manage diabetes
  • Planning on staying in the San Diego area for the next 6 months
  • Willing to select plant-based foods from a "menu" and eat the selected foods provided by the study team
  • Have access to the internet and a computer
  • Willing to view 4 weekly educational classes online, followed by periodic telephone and email contacts
  • Agree to schedule and complete periodic questionnaires and measurements during up to four total online appointments

You CAN'T join if...

  • Alcoholism, smoking and recent cardiovascular events
  • Individuals will be excluded if they report any dietary restrictions, allergies or preferences
  • Unsuitability based on screening visit


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

Lead Scientist at UCSD

  • Ryan Bradley, ND, MPH
    Dr. Bradley received his Doctor of Naturopathy degree from Bastyr University and his Master of Public Health degree from the University of Washington. At UCSD, Dr. Bradley is a member of the Center of Excellence on Research and Training in Integrative Health Research Committee, the Krupp Endowment Research Committee, and is a faculty and mentor for the Arterial Research T32 program.


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