Effects of Walnuts on Central Blood Pressure, Arterial Stiffness Indices, Lipoproteins, and Other CVD Risk Factors

NCT02210767 | Completed

• 1 other identifier: PKE ALA
• Study Type: interventional
• Target: 46
• Locations: 1 country
• Sites: 1

Brief Summary

This study will evaluate the effects of walnut-derived ALA and bioactives on multiple CVD risk factors, including central blood pressure, arterial stiffness indices, inflammatory markers, urinary isoprostanes, vascular adhesion markers, and changes in lipids and lipoproteins. Gut microbiome changes due to walnut consumption will also be assessed using the 16S rRNA gene.

Conditions

Cardiovascular Disease

Outcome Measures

Primary Outcomes (1)

• Change from baseline in central blood pressure at the end of diet period 1 (week 6), end of diet period 2 (week 14), and end of diet period 3 (week 22)

  End of diet period 1 (week 6), end of diet period 2 (week 14), end of diet period 3 (week 22)

Secondary Outcomes (12)

• Change in 24-hour ambulatory blood pressure

  Week 0, end of diet period 1 (week 6), end of diet period 2 (week 14), end of diet period 3 (week 22)

• Change in indices of arterial stiffness (pulse wave velocity)

  Week 0, end of diet period 1 (week 6), end of diet period 2 (week 14), end of diet period 3 (week 22)

• Change in lipoprotein particle size

  Week 0, end of diet period 1 (week 6), end of diet period 2 (week 14), end of diet period 3 (week 22)

• Change in inflammatory cytokines (tumor necrosis factor-alpha and interleukin-6)

  Week 0, end of diet period 1 (week 6), end of diet period 2 (week 14), end of diet period 3 (week 22)

• Change in the composition of the gut microbiome

  Week 0, end of diet period 1 (week 6), end of diet period 2 (week 14), end of diet period 3 (week 22)

Study Arms (3)

Walnut Diet

EXPERIMENTAL

Provides \~2 oz. walnuts/day (2-3% of total calories from alpha-linolenic acid \[ALA\])

Other: Walnut Diet

Walnut Control Diet

ACTIVE COMPARATOR

Provides same fatty acid profile (\<7% SFA, 9% MUFA, 14-15% PUFA, 2-3% ALA) as Walnut Diet, but is devoid of walnuts and their bioactives

Other: Walnut Control Diet

Low ALA Diet

PLACEBO COMPARATOR

Provides similar macronutrient and linoleic acid profile but replaces ALA with oleic acid (\<7% SFA, 12% MUFA, 12% PUFA, 0.5% ALA)

Other: Low ALA Diet

Interventions

Walnut Diet OTHER

2 oz. walnuts/day (2-3% of total calories from ALA)

Walnut Diet

Walnut Control Diet OTHER

2-3% ALA but no walnuts provided

Walnut Control Diet

Low ALA Diet OTHER

ALA replaced by oleic acid

Low ALA Diet

Eligibility Criteria

• Age: 30 Years - 65 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Aged 30-65 years
• BMI greater than 25 and less than or equal to 40 kg/m2
• Non-smokers
• TG \< 350 mg/dL
• LDL-C between the 25-95th percentile from NHANES:
• Males: 105-194 mg/dL
• Females: 98-190 mg/dL
• Stage I hypertension:
• SBP \> 120 mmHg and/or DBP \> 80 mmHg
• SBP \< 160 mmHg and DBP \< 100 mmHg
• Free of established CVD, stroke, diabetes, liver, kidney or autoimmune disease.

You may not qualify if:

• Elevated BP (SBP ≥160 mmHg OR DBP ≥ 100 mmHg)
• A history of myocardial infarction, stroke, diabetes mellitus, liver disease, inflammatory disease, kidney disease, and/or thyroid disease (unless controlled on medication).
• Blood pressure or cholesterol-lowering medication use
• Refusal to discontinue intake of putative cholesterol-lowering supplements (psyllium, fish oil capsules, soy lecithin, niacin, fiber, flax, and phytoestrogens).
• Vegetarianism or other dietary practices that are inconsistent with the test diets
• Nut allergies (Other food allergies will be reviewed on a case-by-case basis)
• Refusal to discontinue nutritional supplements, herbs, vitamins or NSAID's
• Latex allergy
• Pregnant or lactating females

Sponsors & Collaborators

• Penn State University: lead
• California Walnut Commission: collaborator

Study Sites (1)

Penn State University

University Park, Pennsylvania, 16802, United States

Location

Related Publications (10)

• McGuire S. U.S. Department of Agriculture and U.S. Department of Health and Human Services, Dietary Guidelines for Americans, 2010. 7th Edition, Washington, DC: U.S. Government Printing Office, January 2011. Adv Nutr. 2011 May;2(3):293-4. doi: 10.3945/an.111.000430. Epub 2011 Apr 30. No abstract available.

  PMID: 22332062 BACKGROUND

• Sabate J, Fraser GE, Burke K, Knutsen SF, Bennett H, Lindsted KD. Effects of walnuts on serum lipid levels and blood pressure in normal men. N Engl J Med. 1993 Mar 4;328(9):603-7. doi: 10.1056/NEJM199303043280902.

  PMID: 8357360 BACKGROUND

• Zhao G, Etherton TD, Martin KR, West SG, Gillies PJ, Kris-Etherton PM. Dietary alpha-linolenic acid reduces inflammatory and lipid cardiovascular risk factors in hypercholesterolemic men and women. J Nutr. 2004 Nov;134(11):2991-7. doi: 10.1093/jn/134.11.2991.

  PMID: 15514264 BACKGROUND

• Banel DK, Hu FB. Effects of walnut consumption on blood lipids and other cardiovascular risk factors: a meta-analysis and systematic review. Am J Clin Nutr. 2009 Jul;90(1):56-63. doi: 10.3945/ajcn.2009.27457. Epub 2009 May 20.

  PMID: 19458020 BACKGROUND

• West SG, Krick AL, Klein LC, Zhao G, Wojtowicz TF, McGuiness M, Bagshaw DM, Wagner P, Ceballos RM, Holub BJ, Kris-Etherton PM. Effects of diets high in walnuts and flax oil on hemodynamic responses to stress and vascular endothelial function. J Am Coll Nutr. 2010 Dec;29(6):595-603. doi: 10.1080/07315724.2010.10719898.

  PMID: 21677123 BACKGROUND

• Estruch R, Ros E, Salas-Salvadó J, Covas MI, Corella D, Arós F, Gómez-Gracia E, Ruiz-Gutiérrez V, Fiol M, Lapetra J, Lamuela-Raventos RM, Serra-Majem L,Pintó X, Basora J, Muñoz MA, Sorlí JV, Martínez JA, Martínez-González MA; PREDIMED Study Investigators. Primary prevention of cardiovascular disease with a Mediterranean diet. N Engl J Med. 2013;368:1279-1290.

  BACKGROUND

• Zhang J, Grieger JA, Kris-Etherton PM, Thompson JT, Gillies PJ, Fleming JA, Vanden Heuvel JP. Walnut oil increases cholesterol efflux through inhibition of stearoyl CoA desaturase 1 in THP-1 macrophage-derived foam cells. Nutr Metab (Lond). 2011 Aug 26;8:61. doi: 10.1186/1743-7075-8-61.

  PMID: 21871057 BACKGROUND

• Petersen KS, Chandra M, Chen See JR, Leister J, Jafari F, Tindall A, Kris-Etherton PM, Lamendella R. Walnut consumption and gut microbial metabolism: Results of an exploratory analysis from a randomized, crossover, controlled-feeding study. Clin Nutr. 2023 Nov;42(11):2258-2269. doi: 10.1016/j.clnu.2023.09.023. Epub 2023 Sep 28.

  PMID: 37826992 DERIVED

• Tindall AM, McLimans CJ, Petersen KS, Kris-Etherton PM, Lamendella R. Walnuts and Vegetable Oils Containing Oleic Acid Differentially Affect the Gut Microbiota and Associations with Cardiovascular Risk Factors: Follow-up of a Randomized, Controlled, Feeding Trial in Adults at Risk for Cardiovascular Disease. J Nutr. 2020 Apr 1;150(4):806-817. doi: 10.1093/jn/nxz289.

  PMID: 31848609 DERIVED

• Tindall AM, Petersen KS, Skulas-Ray AC, Richter CK, Proctor DN, Kris-Etherton PM. Replacing Saturated Fat With Walnuts or Vegetable Oils Improves Central Blood Pressure and Serum Lipids in Adults at Risk for Cardiovascular Disease: A Randomized Controlled-Feeding Trial. J Am Heart Assoc. 2019 May 7;8(9):e011512. doi: 10.1161/JAHA.118.011512.

  PMID: 31039663 DERIVED

MeSH Terms

Conditions

Cardiovascular Diseases

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: OTHER
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: July 17, 2014
• First Posted: August 7, 2014
• Study Start: August 1, 2014
• Primary Completion: April 1, 2018
• Study Completion: April 1, 2018
• Last Updated: August 21, 2023

Record last verified: 2023-08

Locations

US (1)