The Metabolic Effect of Walnuts in Healthy Subjects (WALDI)

The Metabolic Effect of Walnut Consumption in Healthy Men and Healthy Postmenopausal Women Substituting Walnuts for Different Food Components

The objectives of the proposed study are to assess whether the metabolic effects of walnut consumption depends on which food components the walnuts substitute (i.e. carbohydrates; saturated fatty acids) and whether it is important to consume walnuts as snacks or with meals.

Study Overview

• Status: Completed
• Conditions: Lipid Metabolism Disorders
• Intervention / Treatment: Other: walnuts

Detailed Description

The objectives of the proposed study are to assess whether the metabolic effects of walnut consumption depends on which food components the walnuts substitute (i.e. carbohydrates; saturated fatty acids) and whether it is important to consume walnuts as snacks or with meals.

The metabolic effects of walnut consumption may not only relate to the ingested walnuts but also to what is not eaten when walnuts are consumed. We want to evaluate whether the metabolic changes are more pronounced if study participants are instructed to reduce carbohydrates or saturated fatty acids to remain on an isocaloric diet. In a third group we will test what food is omitted if no specific instructions are given. Furthermore half of the subjects in each group will be instructed to eat walnuts with meals and half as snacks.

• Study Type: Interventional
• Enrollment (Actual): 180
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Germany
  • Munich, Germany, 81377
    • Medical Department 2, University Munich

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 50 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Postmenopausal healthy women and healthy men
• Age >50 yrs
• Written informed consent prior to study participation

Exclusion Criteria:

• Known allergy to nuts
• Evidence of alcohol (women >70g/week, men >140g/week), tabacco or drug abuse
• Obesity ≥35 kg/m2
• Diabetes mellitus
• Hypertension >140/90 mmHg or history of hypertension
• LDL-cholesterol >190 mg/dl, Triglycerides > 350 mg/dl
• History of atherosclerotic disease
• Liver disease of any etiology
• Kidney disease of any etiology (GFR < 60 ml/min/1.73)
• Uncontrolled thyroid disease or other endocrine diseases
• Acute or chronic inflammatory diseases
• Active malignancy
• Current or previous (within 3 months) treatment with antidiabetic drugs, hypolipidemic drugs, antihypertensive drugs, anti-inflammatory drugs, vitamin E, hormonal replacement therapy
• major surgical intervention within 3 months (or planned)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: walnut-CH; Western type diet including walnuts (43g/day); Walnuts substitute carbohydrates	Other: walnuts; consumption of 43 g walnuts per day
Experimental: Walnut-SFA; Western type diet including walnuts (43g/day); Walnuts substitute saturated fatty acids	Other: walnuts; consumption of 43 g walnuts per day
Experimental: Walnut-LIB; Western type diet including walnuts (43g/day); no specific recommendation	Other: walnuts; consumption of 43 g walnuts per day
No Intervention: Control; Isocaloric western type diet w/o nuts, nut butters or nut oils of any kind

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Non-HDL-cholesterol	8 weeks

Secondary Outcome Measures

Outcome Measure	Time Frame
LDL-cholesterol	8 weeks
total-cholesterol	8 weeks
apoB	8 weeks
triglycerides	8 weeks
fasting glucose	8 weeks
HOMA index	8 weeks
caloric intake	8 weeks
ratio CH:fat:protein	8 weeks
ratio SFA:MUFA:PUFA	8 weeks

Collaborators and Investigators

• Sponsor: Ludwig-Maximilians - University of Munich
• Investigators: Principal Investigator: Klaus G Parhofer, MD, Ludwig-Maximilians - University of Munich

Study record dates

Study Major Dates

• Study Start: December 1, 2014
• Primary Completion (Actual): July 1, 2016
• Study Completion (Actual): July 1, 2017

Study Registration Dates

• First Submitted: December 29, 2014
• First Submitted That Met QC Criteria: December 29, 2014
• First Posted (Estimate): December 31, 2014

Study Record Updates

• Last Update Posted (Actual): August 29, 2017
• Last Update Submitted That Met QC Criteria: August 28, 2017
• Last Verified: August 1, 2017

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Metabolic Diseases; Lipid Metabolism Disorders
• Other Study ID Numbers: WALNUT-2