Black Walnuts and Health

Not Applicable

Completed

• Conditions: Healthy
• Interventions: Other: Black walnut; Other: Control; Other: English walnut

• Registration Number: NCT04849949
• Lead Sponsor: University of Georgia

Brief Summary

Walnuts are a nutrient dense food, but most health research is on English walnuts (EW). Black walnuts (BW) contain a different antioxidant and fatty acid profile, and more protein, compared to EW. The purpose of the study was to compare postprandial responses following the consumption of 3 breakfast meals containing either butter (control), BW, or EW.

Detailed Description

This study was a randomized, double-blind control trial consisting of 3 study visits for 3 different treatments. The treatments were high-fat breakfast muffins containing either butter (control), black walnuts, or English walnuts. The investigators recruited healthy, normal-weight adults between the ages of 15 and 45y. Study visits were completed in a random order with at least 72 hours between each visit. Anthropometrics, questionnaires, and fasting and postprandial blood samples were collected at each visit.

Hypothesis: The walnut-containing meals would mitigate post-meal increases in glucose, insulin, triglycerides (TG), and lipid peroxidation while improving all measures of subjective appetite and TAC compared to the traditional meal without nuts.

Study Timeline

• Study Start: 2017-08-10
• Primary Completion: 2018-02-27
• Study Completion: 2018-02-27
• Status Verified: 2021-04
• Study First Submitted: 2021-04-07
• Study First Submitted QC: 2021-04-13
• Last Update Submitted: 2021-04-13
• Study First Posted: 2021-04-20
• Last Update Posted: 2021-04-20

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 34

Inclusion Criteria

• Healthy adult men and women
• Normal-weight (body mass index = 18-24.9kg/m2)

Exclusion Criteria

• Allergies to test meal ingredients (gluten, eggs, or nuts)
• Medication/supplement usage
• Chronic disease
• Pregnancy or plans to become pregnant
• Special diets
• Tobacco use

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Black walnut	Black walnut	Participants in this group received a muffin in which part of the butter was substituted out for black walnuts.
Control	Control	Participants in this group received a traditional muffin with butter as the predominant source of fat.
English Walnut	English walnut	Participants in this group received a muffin in which part of the butter was substituted out for English walnuts.

Primary Outcome Measures

Name	Time	Method
Change in triglycerides (TG) and glucose responses	Change from baseline to 3 hours postprandially	TG (mg/dL) and glucose (mg/dL)
Change in total antioxidant capacity	Change from baseline to 3 hours postprandially	Total antioxidant capacity (uM trolox equivalents) measured via Oxygen Radical Absorbance Capacity (ORAC) assay.
Change in lipid peroxidation	Change from baseline to 3 hours postprandially	Malondialdehyde (MDA) (uM) measured via Thiobarbituric acid reactive substances (TBARS) assay
Change in insulin	Change from baseline to 3 hours postprandially	Insulin (uU/mL)

Secondary Outcome Measures

Name	Time	Method
Change in angiopoietin-like proteins-3 (ANGPTL3) and -4 (ANGPTL4) responses	Change from baseline to 3 hours postprandially	ANGPTL3 (pg/mL) and ANGPTL4 (pg/mL)
Change in hunger and satiety responses	Change from baseline to 3 hours postprandially	Hunger, fullness, prospective consumption, and desire to eat measured via a Visual Analog Scale (VAS) (mm). The range of scores on the continuous VAS is 0-100 mm. Zero represents no hunger, fullness, prospective consumption, and desire to eat, while 100 represents the greatest feeling of these outcomes.

Trial Locations

Locations (1)

University of Georgia - Department of Foods and Nutrition & Department of Food Science and Technology; 🇺🇸 Athens, Georgia, United States