The Measured Energy Value of Walnuts in the Human Diet

NCT01832909 | Completed

• 1 other identifier: HS43
• Study Type: interventional
• Target: 18
• Locations: 1 country
• Sites: 1

Brief Summary

The objective of this study is to measure the energy value of walnuts in the human diet and study molecular mechanisms that may help explain the beneficial health effects of walnuts. The hypothesis is that there will be less metabolizable energy in walnuts due to decreased fat digestibility.

Conditions

Metabolizable Energy of Walnuts

Keywords

metabolizable energy; walnuts; Atwater factors; energy value

Outcome Measures

Primary Outcomes (1)

• Metabolizable Energy

  Metabolizable energy content will be calculated according to the methods of Novotny et al. (2012). Fat, protein, and fiber digestibility will be calculated and the effect of walnuts on nutrient digestibility will be assessed.

  Each three weeks, up to 6 weeks

Secondary Outcomes (3)

• Gene expression

  At the end of each 3-week intervention period

• Biomarkers of oxidative stress/inflammation

  End of each 3-week intervention period

• Measure of walnut nutrients and metabolites

  End of each 3-week intervention period

Study Arms (2)

Walnut Diet first, then Control Diet

EXPERIMENTAL

Controlled diet with 1.5 oz/d of walnuts, followed by controlled diet without walnuts.

Other: Walnut Diet; Other: Control Diet

Control Diet first, then Walnut Diet

EXPERIMENTAL

Controlled diet without almonds first (control), then controlled diet with 1.5 oz/d of almonds.

Other: Walnut Diet; Other: Control Diet

Interventions

Walnut Diet OTHER

Controlled diet with 1.5 oz/d of walnuts.

Control Diet first, then Walnut Diet; Walnut Diet first, then Control Diet

Control Diet OTHER

Controlled diet without walnuts.

Control Diet first, then Walnut Diet; Walnut Diet first, then Control Diet

Eligibility Criteria

• Age: 25 Years - 65 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age 25 to 65 years at beginning of study
• Body mass index between 20 and 38 kg/m2
• Fasting glucose \< 126 mg/dl
• Blood pressure \< 160/100 (controlled with certain medications)
• Fasting total blood cholesterol \< 280 mg/dl
• Fasting triglycerides \< 300 mg/dl

You may not qualify if:

• Presence of kidney disease, liver disease, gout, hyperthyroidism, untreated or unstable hypothyroidism, certain cancers, gastrointestinal disease, pancreatic disease, other metabolic diseases, or malabsorption syndromes
• Women who have given birth during the previous 12 months
• Pregnant women or women who plan to become pregnant or become pregnant during the study
• Lactating women
• Type 2 diabetes requiring the use of oral antidiabetic agents or insulin
• History of bariatric or certain other surgeries related to weight control
• Smokers or other tobacco users (during 6 months prior to the start of the study)
• Antibiotic use during the intervention or for 3 weeks prior to any intervention period
• History of eating disorders or other dietary patterns which are not consistent with the dietary intervention (e.g., vegetarians, very low fat diets, high protein diets)
• Volunteers who have lost 10% of body weight within the last 12 months
• Known (self-reported) allergy or adverse reaction to walnuts or other nuts
• Unable or unwilling to give informed consent or communicate with study staff
• Other medical, psychiatric, or behavioral factors that in the judgment of the Principal Investigator may interfere with study participation or the ability to follow the intervention protocol

Sponsors & Collaborators

• USDA Beltsville Human Nutrition Research Center: lead
• California Walnut Board: collaborator

Study Sites (1)

USDA Beltsville Human Nutrition Research Center

Beltsville, Maryland, 20705, United States

Location

Related Publications (3)

• Novotny JA, Gebauer SK, Baer DJ. Discrepancy between the Atwater factor predicted and empirically measured energy values of almonds in human diets. Am J Clin Nutr. 2012 Aug;96(2):296-301. doi: 10.3945/ajcn.112.035782. Epub 2012 Jul 3.

  PMID: 22760558 BACKGROUND

• Holscher HD, Guetterman HM, Swanson KS, An R, Matthan NR, Lichtenstein AH, Novotny JA, Baer DJ. Walnut Consumption Alters the Gastrointestinal Microbiota, Microbially Derived Secondary Bile Acids, and Health Markers in Healthy Adults: A Randomized Controlled Trial. J Nutr. 2018 Jun 1;148(6):861-867. doi: 10.1093/jn/nxy004.

  PMID: 29726951 DERIVED

• Baer DJ, Gebauer SK, Novotny JA. Walnuts Consumed by Healthy Adults Provide Less Available Energy than Predicted by the Atwater Factors. J Nutr. 2016 Jan;146(1):9-13. doi: 10.3945/jn.115.217372. Epub 2015 Nov 18.

  PMID: 26581681 DERIVED

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Intervention Model: CROSSOVER
• Sponsor Type: FED
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Research Physiologist

Study Record Dates

• First Submitted: April 8, 2013
• First Posted: April 16, 2013
• Study Start: April 1, 2013
• Primary Completion: June 1, 2013
• Study Completion: June 1, 2013
• Last Updated: September 17, 2013

Record last verified: 2013-09

Locations

US (1)