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Walnuts to Achieve Lasting NUTrition to Prevent Diabetes

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT03334175
Recruitment Status : Completed
First Posted : November 7, 2017
Last Update Posted : October 2, 2019
Information provided by (Responsible Party):
University of California, San Francisco

Tracking Information
First Submitted Date  ICMJE October 30, 2017
First Posted Date  ICMJE November 7, 2017
Last Update Posted Date October 2, 2019
Actual Study Start Date  ICMJE May 21, 2018
Actual Primary Completion Date August 5, 2019   (Final data collection date for primary outcome measure)
Current Primary Outcome Measures  ICMJE
 (submitted: April 11, 2018)
  • Number of participants recruited and retained [ Time Frame: 12 weeks ]
    Number of participants recruited and retained
  • Adherence to the intervention [ Time Frame: 12 weeks ]
    Adherence through food diaries, palatability through a visual analog scale
Original Primary Outcome Measures  ICMJE
 (submitted: November 2, 2017)
  • Feasibility [ Time Frame: 12 weeks ]
    Number of participants recruited and retained
  • Acceptability [ Time Frame: 12 weeks ]
    adherence through food diaries
Change History
Current Secondary Outcome Measures  ICMJE
 (submitted: November 2, 2017)
  • Diet quality [ Time Frame: 0 weeks and 12 weeks ]
    Healthy Eating Index-2010 Score (0 - 100)
  • Fasting glucose [ Time Frame: 0 weeks and 12 weeks ]
    Serum fasting glucose
  • A1c [ Time Frame: 0 weeks and 12 weeks ]
  • Lipids [ Time Frame: 0 weeks and 12 weeks ]
    Serum lipid levels
Original Secondary Outcome Measures  ICMJE Same as current
Current Other Pre-specified Outcome Measures
 (submitted: November 2, 2017)
Metabolomics [ Time Frame: 0 wees and 12 weeks ]
Serum Amino Acid Levels
Original Other Pre-specified Outcome Measures Same as current
Descriptive Information
Brief Title  ICMJE Walnuts to Achieve Lasting NUTrition to Prevent Diabetes
Official Title  ICMJE Walnuts to Achieve Lasting NUTrition to Prevent Diabetes (WALNUT-Diabetes)
Brief Summary Prediabetes is a precursor of type 2 diabetes and an independent risk factor for cardiovascular disease, and currently affects one-quarter of the population of the United States. Individuals of overweight or obese BMI are at particular high risk for incident diabetes. A major modifiable risk factor for type 2 diabetes is poor dietary quality, and improvement of dietary quality can effectively delay and even prevent type 2 diabetes. Interventions to improve dietary quality thus far, however, rely on short-term intensive clinically designed meals replacing the entire diet which have poor sustainability. Persistent improvements to daily dietary patterns are often difficult without directed guidance, and overall dietary quality in the United States remains poor. The identification of a practical, daily dietary intervention to improve dietary quality and prevent diabetes in those at high risk remains unknown. The investigators propose to enroll 40 individuals with diagnosed prediabetes into a randomized controlled pilot study and provide a daily walnut supplementation intervention to determine feasibility and acceptability of the supplement. The investigators will then determine preliminary efficacy on metabolic markers and will investigate associations between dietary quality and circulating levels of branched-chain amino acids. The goal is to implement a whole-food supplement to improve dietary quality in patients with prediabetes as a tool for future type 2 diabetes prevention.
Detailed Description Not Provided
Study Type  ICMJE Interventional
Study Phase  ICMJE Phase 1
Phase 2
Study Design  ICMJE Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Prevention
Condition  ICMJE
  • PreDiabetes
  • Overweight and Obesity
Intervention  ICMJE Drug: Walnuts
1 ounce of individually wrapped, raw walnuts to be consumed daily replacing a high-refined carbohydrate food.
Study Arms  ICMJE
  • Experimental: Walnuts Now
    Will receive and be instructed to consume 1-oz individually wrapped daily walnut supplement packages for 12 weeks during intervention.
    Intervention: Drug: Walnuts
  • No Intervention: Walnuts Later
    Will receive diet and exercise guidance at beginning of study. At end of study, will receive 12 weeks of a walnut supply to be consumed at their discretion after the study is complete.
Publications * Not Provided

*   Includes publications given by the data provider as well as publications identified by Identifier (NCT Number) in Medline.
Recruitment Information
Recruitment Status  ICMJE Completed
Actual Enrollment  ICMJE
 (submitted: March 15, 2019)
Original Estimated Enrollment  ICMJE
 (submitted: November 2, 2017)
Actual Study Completion Date  ICMJE August 5, 2019
Actual Primary Completion Date August 5, 2019   (Final data collection date for primary outcome measure)
Eligibility Criteria  ICMJE

Inclusion Criteria:

  1. Male or female between 18-65 years of age at baseline living in the San Francisco Bay area.
  2. BMI>25 m/kg2 (or >23 m/kg2 for individuals of Asian or South Asian ethnicity)
  3. Documentation of prediabetes diagnosis as evidenced by the following criteria:

    1. A fasting glucose 100-125 mg/dL, or a HbA1c measurement of 5.7-6.4%, OR a diagnosis of "prediabetes" or "impaired fasting glucose" in the past 6 months, identified through an electronic medical record query from patients at UCSF and through outside recruitment in the surrounding community
    2. We will confirm eligibility of potential participants by repeating fasting capillary blood glucose measurements at the baseline visit to ensure that they have prediabetes
  4. Written informed consent and ability for subject to comply with the requirements of the study.

Exclusion Criteria:

  1. Pregnant or breastfeeding women at enrollment.
  2. Presence of a condition or abnormality that in the opinion of the Investigator would compromise the safety of the patient or the quality of the data, such as diverticulosis or diverticulitis.
  3. Tree or peanut allergies
  4. Unwilling to consume a daily walnut supplement.
  5. Diagnosis of diabetes
  6. On glucose lowering medications
  7. Dietician-managed dietary intake, or personal or medical dietary restrictions that do not allow consumption of walnuts
  8. Malabsorptive conditions including intestinal bypass surgery, pancreatitis, inflammatory bowel disease
Sex/Gender  ICMJE
Sexes Eligible for Study: All
Ages  ICMJE 18 Years to 65 Years   (Adult, Older Adult)
Accepts Healthy Volunteers  ICMJE No
Contacts  ICMJE Contact information is only displayed when the study is recruiting subjects
Listed Location Countries  ICMJE United States
Removed Location Countries  
Administrative Information
NCT Number  ICMJE NCT03334175
Other Study ID Numbers  ICMJE 4000-128070-125731P-44
Has Data Monitoring Committee No
U.S. FDA-regulated Product
Studies a U.S. FDA-regulated Drug Product: Yes
Studies a U.S. FDA-regulated Device Product: No
Product Manufactured in and Exported from the U.S.: No
IPD Sharing Statement  ICMJE Not Provided
Responsible Party University of California, San Francisco
Study Sponsor  ICMJE University of California, San Francisco
Collaborators  ICMJE Not Provided
Investigators  ICMJE
Principal Investigator: Meghana Gadgil, MD University of California, San Francisco
PRS Account University of California, San Francisco
Verification Date September 2019

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP