Walnut Ingestion in Adults at Risk for Diabetes: Effects on Body Composition, Diet Quality, and Cardiac Risk Measures

NCT02330848 | Completed

• 1 other identifier: 2011-16
• Study Type: interventional
• Target: 112
• Locations: 1 country
• Sites: 1

Brief Summary

Proposed is a randomized, controlled, modified Latin square parallel design study with two treatment arms to examine walnut consumption effects on diet quality, body composition, and markers of cardiovascular risk in adults at risk for diabetes over a 6-month period. A modified crossover design (Latin square)27-29 will allow for both paired and unpaired analyses.

Conditions

Diabetes

Keywords

Obesity; Walnuts; Endothelial Function; Adults at risk

Outcome Measures

Primary Outcomes (1)

• Diet Quality assessed using the Alternative Healthy Eating Index (AHEI)

  To help the study team track any variation in dietary pattern over the course of the study, all participants will be asked at five different time points to provide information on the foods and beverages that they consumed. A 3-day food diary record will be collected along with a one 24-hour recall using a web-based Automated Self-Administered 24-Hour Recall (ASA24) (available from the National Cancer Institute at http://riskfactor.cancer.gov/tools/instruments/asa24/) which will guide them through the process of completing the recall data. Diet quality will be assessed using the Alternative Healthy Eating Index (AHEI).

  6 months

Secondary Outcomes (7)

• Body Composition measured using bioelectrical impedance analysis and SC-240 Body Composition Analyzer

  6 months

• Endothelial Function (EF) Assessment using the brachial artery reactivity studies (BARS) methodology

  6 months

• Anthropometric Measures

  6 months

• Lipid Profile

  6 months

• Fasting Blood Glucose

  6 months

Study Arms (2)

Walnut Ad libitum diet

ACTIVE COMPARATOR

Participants will be provided 392 grams of walnuts per week (56g or 2 oz/day) to include in their diet. Their calorie intake will not be subsequently monitored or regulated, and thus will be allowed to float ad libitum.

Dietary Supplement: Walnut Ad libitum diet

Walnut Calorie Controlled

ACTIVE COMPARATOR

The intervention group participants will meet with a registered dietitian and receive instructions and recipes for inclusion of 392 grams of walnuts per week (56g or 2 oz/day) in their meal plan. Participants will receive on-going instruction to preserve an isocaloric condition after the addition of walnuts. The study dietitian will customize dietary adjustments to make room for walnuts in the diet, while accommodating the priorities of each study participant. The general approach will emphasize general reduction in portion sizes; participants will also receive advice, based on baseline dietary intake analysis, of food eliminations that they might want to consider.

Dietary Supplement: Walnut Calorie controlled

Interventions

Walnut Ad libitum diet DIETARY_SUPPLEMENT

Participants will be provided 392 grams of walnuts per week (56g or 2 oz/day) to include in their diet. Their calorie intake will not be subsequently monitored or regulated, and thus will be allowed to float ad libitum

Walnut Ad libitum diet

Walnut Calorie controlled DIETARY_SUPPLEMENT

The intervention group participants will meet with a registered dietitian and receive instructions and recipes for inclusion of 392 grams of walnuts per week (56g or 2 oz/day) in their meal plan for 6 months.

Walnut Calorie Controlled

Eligibility Criteria

• Age: 25 Years - 75 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Male and female age 25-75 years;
• Non-smoker;
• High risk for diabetes, defined as meeting at least one of the criteria listed below:
• a. Overweight with increased waist circumference; b.Pre-diabetes: fasting blood glucose \>100mg/dL and \<126mg/dL or HbA1C 5.7-6.4 % c. Metabolic syndrome, i.e. meet three out of five of the following criteria: i.Blood pressure \>130/85 mmHg or currently taking antihypertensive medication; ii. Fasting plasma glucose (FPG) \>100 mg/dL (6.1 mmol/L); iii.Serum triglycerides level (TG)\>150 mg/dL (1.69 mmol/L); iv. High-density lipoprotein (HDL) cholesterol \< 40 mg/dL (1.04 mmol/L) in men, and \< 50 mg/dL (1.29 mmol/L) in women; v. Overweight (BMI ≥25kg/m²) with waist circumference of more than 40 inches (102 cm) for men and more than 35 inches (88 cm) for women.

You may not qualify if:

• Allergy to walnuts or any other nuts;
• Anticipated inability to complete study protocol for any reason;
• Current eating disorder;
• Restricted diets by choice (i.e., vegetarian, vegan);
• Receiving pharmacotherapy for obesity, including appetite suppressant
• Unstable use of lipid-lowering, antihypertensive medications or aspirin (i.e. dose has changed in the three months prior to enrollment) or unwilling to refrain from taking medication for 12 hours prior to endothelial function scanning;
• Regular use of high doses of vitamin E (\>400IU/day) or vitamin C (\>500mg/day); fish oil, flaxseed oil, omega-3 fatty acid and fiber supplement unless welling to discontinue supplementation for the study duration.
• Use of insulin, glucose-sensitizing medication, vasoactive medication (including glucocorticoids, antineoplastic agents, psychoactive agents, or bronchodilators);
• Diagnosed diabetes;
• Diagnosed sleep apnea;
• Established cardiovascular disease (including symptomatic coronary artery disease (CAD), myocardial infarction, peripheral vascular disease, congestive heart failure, carotid stenosis);
• Coagulopathy, known bleeding diathesis, or history of clinically significant hemorrhage; current use of warfarin;
• Regular exercise defined as participation in moderate-intensity exercise \> 150 minutes/week.
• Substance abuse (chronic alcoholism, other chemical dependency)
• Any unstable medical condition that would limit the ability of a subject to participate fully in the trial (e.g., cancer, AIDS, tuberculosis, psychotic disorder)

Sponsors & Collaborators

• Griffin Hospital: lead

Study Sites (1)

Yale-Griffin Prevention Research Center

Derby, Connecticut, 06418, United States

Location

Related Publications (3)

• Njike VY, Costales VC, Petraro P, Annam R, Yarandi N, Katz DL. The Resulting Variation in Nutrient Intake With the Inclusion of Walnuts in the Diets of Adults at Risk for Type 2 Diabetes: A Randomized, Controlled, Crossover Trial. Am J Health Promot. 2019 Mar;33(3):430-438. doi: 10.1177/0890117118791120. Epub 2018 Aug 1.

  PMID: 30068215 DERIVED

• Njike VY, Yarandi N, Petraro P, Ayettey RG, Treu JA, Katz DL. Inclusion of walnut in the diets of adults at risk for type 2 diabetes and their dietary pattern changes: a randomized, controlled, cross-over trial. BMJ Open Diabetes Res Care. 2016 Oct 19;4(1):e000293. doi: 10.1136/bmjdrc-2016-000293. eCollection 2016.

  PMID: 27843557 DERIVED

• Njike VY, Ayettey R, Petraro P, Treu JA, Katz DL. Walnut ingestion in adults at risk for diabetes: effects on body composition, diet quality, and cardiac risk measures. BMJ Open Diabetes Res Care. 2015 Oct 19;3(1):e000115. doi: 10.1136/bmjdrc-2015-000115. eCollection 2015.

  PMID: 26688734 DERIVED

MeSH Terms

Conditions

Diabetes Mellitus; Obesity

Condition Hierarchy (Ancestors)

Glucose Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases; Endocrine System Diseases; Overweight; Overnutrition; Nutrition Disorders; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Officials

• David L. Katz, MD, MPH

  Yale-Griffin Prevention Research Center

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: INVESTIGATOR
• Purpose: PREVENTION
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: April 2, 2014
• First Posted: January 5, 2015
• Study Start: February 1, 2012
• Primary Completion: September 1, 2013
• Study Completion: April 1, 2014
• Last Updated: March 26, 2020

Record last verified: 2020-03

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)