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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

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.

Condition or disease Intervention/treatment Phase
PreDiabetes Overweight and Obesity Drug: Walnuts Phase 1 Phase 2

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Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 18 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Prevention
Official Title: Walnuts to Achieve Lasting NUTrition to Prevent Diabetes (WALNUT-Diabetes)
Actual Study Start Date : May 21, 2018
Actual Primary Completion Date : August 5, 2019
Actual Study Completion Date : August 5, 2019

Arm Intervention/treatment
Experimental: Walnuts Now
Will receive and be instructed to consume 1-oz individually wrapped daily walnut supplement packages for 12 weeks during intervention.
Drug: Walnuts
1 ounce of individually wrapped, raw walnuts to be consumed daily replacing a high-refined carbohydrate food.

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.

Primary Outcome Measures :
  1. Number of participants recruited and retained [ Time Frame: 12 weeks ]
    Number of participants recruited and retained

  2. Adherence to the intervention [ Time Frame: 12 weeks ]
    Adherence through food diaries, palatability through a visual analog scale

Secondary Outcome Measures :
  1. Diet quality [ Time Frame: 0 weeks and 12 weeks ]
    Healthy Eating Index-2010 Score (0 - 100)

  2. Fasting glucose [ Time Frame: 0 weeks and 12 weeks ]
    Serum fasting glucose

  3. A1c [ Time Frame: 0 weeks and 12 weeks ]

  4. Lipids [ Time Frame: 0 weeks and 12 weeks ]
    Serum lipid levels

Other Outcome Measures:
  1. Metabolomics [ Time Frame: 0 wees and 12 weeks ]
    Serum Amino Acid Levels

Information from the National Library of Medicine

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, Learn About Clinical Studies.

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Ages Eligible for Study:   18 Years to 65 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

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

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT03334175

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United States, California
University of California, San Francisco
San Francisco, California, United States, 94143
Sponsors and Collaborators
University of California, San Francisco
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Principal Investigator: Meghana Gadgil, MD University of California, San Francisco
  Study Documents (Full-Text)

Documents provided by University of California, San Francisco:
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Responsible Party: University of California, San Francisco Identifier: NCT03334175    
Other Study ID Numbers: 4000-128070-125731P-44
First Posted: November 7, 2017    Key Record Dates
Last Update Posted: October 2, 2019
Last Verified: September 2019

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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
Additional relevant MeSH terms:
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Prediabetic State
Body Weight
Signs and Symptoms
Diabetes Mellitus
Glucose Metabolism Disorders
Metabolic Diseases
Endocrine System Diseases