Pecan Snacking and Blood Sugar in Prediabetes

Is this trial a fit for you?

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This is a 16-week randomized controlled trial comparing two snack patterns in adults with prediabetes. Participants will be assigned to either replace their snacks with 1.5 ounces of pecans daily or continue their usual diet. The study will measure blood sugar, heart health markers, and dietary intake at study start and end. Testing occurs at baseline and after 16 weeks to see if pecan snacking affects cardiometabolic outcomes.

Why it matters

Who can join: the full rules

Inclusion Criteria:

* Age 25-65 years
* Prediabetes assessed by an HbA1c of 5.7-6.4% at screening
* BMI 25-40 kg/m2 at screening
* Low habitual nut consumption (\<3.5 oz-eq/week) assessed at the telephone screening
* Regularly eats snacks higher in saturated fat and/or added sugars assessed at the telephone screening

Exclusion Criteria:

* LDL-C ≥190 mg/dL at screening
* Hemoglobin \<13.2 g/dL at screening
* Fasting triglycerides \>350 mg/dL at screening
* ≥10% change in body weight within the 6 months prior to enrollment
* Blood pressure \>140/90 mmHg at screening
* Type 1 or type 2 diabetes
* Prescription of anti-hypertensive, lipid-lowering, or glucose-lowering drugs
* Intake of supplements or over-the-counter medications that affect the outcomes of interest (i.e., lipid, blood pressure, or glucose lowering; vitamin C or multi-vitamins containing vitamin C) and are unwilling to cease during the study period.
* History of liver, kidney, or autoimmune disease
* Prior cardiovascular event (e.g., stroke, heart attack)
* Current pregnancy or intention of pregnancy within the next 12 months
* Lactation within the prior 6 months
* Pecan allergy/intolerance/sensitivity/dislike
* Unwilling/unable to eat 1.5 oz of pecans every day as a snack during the duration of the study
* Antibiotic use within the prior 4 weeks
* Oral steroid use within the prior 4 weeks
* Use of tobacco or nicotine-containing products within the past 6 months
* History of cancer at any site within the past 10 years (eligible if ≥10 years without recurrence) or non-melanoma skin cancer within the past 5 years (eligible if ≥5 years without recurrence)
* Participation in another clinical trial within 60 days of baseline
* Unwilling to contact study staff before enrolling in other health-related research and avoid participating in any research that may interfere with this study.
* Currently following a restricted or weight-loss diet
* Prior bariatric surgery
* Intake of \>14 alcoholic drinks/week and/or not willing to avoid alcohol consumption for 48 hours prior to test visits
* Principal Investigator discretion related to the potential participant's ability to adhere to the study requirements, including being able to come to attend visits
* Does not speak and/or understand English
* Unwilling to refrain from donating blood or plasma during the study
* Weight \<110 lb
* If a potential participant takes thyroid medicine, abnormal thyroid stimulated hormone (TSH) concentration (TSH outside of normal range), or change in dose of thyroid medication within the last 6 months

Where it's running

• The Pennsylvania State University
  University Park, Pennsylvania, United States Recruiting

Study contacts

• Study coordinator: Kristina Petersen, PhD
• Email: kup63@psu.edu
• Phone: 814-865-7206

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How to take part

1. Review the eligibility criteria above with your treating physician.
2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.