Impact of Cashew Nuts in the Human Diet: Measured Energy Value and Effects on Cardiovascular Disease Risk Factors

This study evaluates the effect of cashew nut consumption on traditional and emerging markers of cardiovascular disease (CVD) risk and determines the usable energy content of a serving of cashew nuts for accurate food labelling.

Study Overview

• Status: Completed
• Conditions: Healthy Volunteers
• Intervention / Treatment: Other: Base Diet; Other: Base Diet with Cashew Nuts

Detailed Description

The cardioprotective effects of nuts have been well documented in the scientific literature; however, most of the research has been done with almonds, walnuts, and pistachios, while studies with cashew nuts are lacking. In addition to the cardiovascular literature, our recent studies measuring the metabolizable energy of nuts have demonstrated that the measured energy value of almonds, pistachios, and walnuts is lower than that predicted using the Atwater factors. However, the measured energy value of cashew nuts is unknown. There are two distinct aims of this study - determining the effects of cashew nut consumption on risk factors of CVD, and determining the energy value of cashew nuts in the human diet. The cardiovascular effects of cashew nuts will be determined by measuring both traditional and emerging risk factors. The metabolizable energy value of cashew nuts will be calculated based on the chemical composition and energy content of the consumed diet and excreta. This will provide a better estimate of the energy value than simply calculating energy value based on Atwater factors.

• Study Type: Interventional
• Enrollment (Actual): 42
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Maryland
    • Beltsville, Maryland, United States, 20705
      • USDA Beltsville Human Nutrition Research Center

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 25 years to 75 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• BMI between 20 and 38 kg/m2
• Fasting glucose ≤ 126 mg/dL
• Blood pressure ≤ 160/100 mm Hg

Exclusion Criteria:

• Presence of kidney disease, liver disease, gout, hyperthyroidism, untreated or unstable hypothyroidism, certain cancers, gastrointestinal disease, pancreatic disease, other metabolic diseases, or malabsorption syndromes
• Use of cholesterol lowering medication
• Use of medication to treat hypertension for less than 6 months
• Active cardiovascular disease (such as a heart attack or procedure within the past six months or participation in a cardiac rehabilitation program within the last six months, stroke, or history/treatment for transient ischemic attacks in the past six months, or documented history of pulmonary embolus in the past six months)
• 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
• Use of prescription or over-the-counter antiobesity medications or supplements (e.g., phenylpropanolamine, ephedrine, caffeine, during and for at least 6 months prior to the start of the study) or history of a surgical intervention for obesity
• Smokers or other tobacco users (during 6 months prior to the start of the study)
• 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)
• Known (self-reported) allergy or adverse reaction to cashew nuts or other nuts
• Unable or unwilling to give informed consent or communicate with study staff
• Self-report of alcohol or substance abuse within the past 12 months and/or current acute treatment or rehabilitation program for these problems (long-term participation in Alcoholics Anonymous is not an exclusion)
• 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

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: Control; Participants will receive a controlled diet (base diet), typical of an American diet, with 0 g/day of cashew nuts (control).	Other: Base Diet; Participants will receive a controlled diet with 0 g/d of cashew nuts. Meals will be prepared using traditional American foods with a macronutrient composition representative of a typical American diet.
Active Comparator: Cashew; Participants will receive a controlled diet, typical of an American diet, with 42 g/day of cashew nuts (base diet with cashew nuts).	Other: Base Diet with Cashew Nuts; Participants will receive a controlled diet with 42 g/d of cashew nuts. Meals will be prepared using traditional American foods with a macronutrient composition representative of a typical American diet.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in lipid/lipoprotein profile will be measured in blood	The following will be measured in the blood on 2 consecutive days at the beginning and end of each 4-week diet period: lipids and lipoproteins, apolipoproteins, lipoprotein particle number/size, and proprotein convertase subtilisin/kexin type 9 (PCSK9).	Week 0, end of diet period 1 (week 4), beginning of diet period 2 (week 6), end of diet period 2 (week 10)
Metabolizable energy will be measured based on energy content of the consumed diet and excreta	The measured metabolizable energy value of cashew nuts will be calculated based on the energy content of the consumed diet and excreta.	Second week of diet period 1 (week 2)
Metabolizable energy will be measured based on energy content of the consumed diet and excreta	The measured metabolizable energy value of cashew nuts will be calculated based on the energy content of the consumed diet and excreta.	Second week of diet period 2 (week 8)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Pulse Wave will be measured using Sphygmocor EXCEL	Pulse wave analysis and pulse wave velocity will be conducted.	Week 0, end of diet period 1 (week 4), beginning of diet period 2 (week 6), end of diet period 2 (week 10)
Markers of vascular health will be measured in blood	Adhesion molecules and endothelin-1 will be measured in the blood.	Week 0, end of diet period 1 (week 4), beginning of diet period 2 (week 6), end of diet period 2 (week 10)
Digestibility (%) will be calculated as (intake - excreted)/intake	Fat, protein, and fiber digestibility will be calculated (%) and the effect of cashew nuts on nutrient digestibility (%) will be assessed.	Second week of diet period 1 (week 2), second week of diet period 2 (week 8)
Change in systemic inflammation will be measured in blood	Markers of systemic inflammation will be measured, such as IL-6, TNF-alpha, serum amyloid A, and CRP.	Week 0, end of diet period 1 (week 4), beginning of diet period 2 (week 6), end of diet period 2 (week 10)
Change in hemostasis will be measured in blood	Fibrinogen and factor VII will be measured in the blood.	Week 0, end of diet period 1 (week 4), beginning of diet period 2 (week 6), end of diet period 2 (week 10)

Collaborators and Investigators

• Sponsor: USDA Beltsville Human Nutrition Research Center

Publications and helpful links

General Publications

• Baer DJ, Novotny JA. Consumption of cashew nuts does not influence blood lipids or other markers of cardiovascular disease in humans: a randomized controlled trial. Am J Clin Nutr. 2019 Feb 1;109(2):269-275. doi: 10.1093/ajcn/nqy242.

Study record dates

Study Major Dates

• Study Start: October 1, 2015
• Primary Completion (Actual): March 1, 2016
• Study Completion (Actual): March 1, 2016

Study Registration Dates

• First Submitted: October 14, 2015
• First Submitted That Met QC Criteria: December 8, 2015
• First Posted (Estimate): December 11, 2015

Study Record Updates

• Last Update Posted (Estimate): May 12, 2016
• Last Update Submitted That Met QC Criteria: May 10, 2016
• Last Verified: May 1, 2016

More Information

Terms related to this study

• Other Study ID Numbers: HS52

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No