title: Walnut-enriched diet reduces fasting non-HDL-cholesterol and apolipoprotein B in healthy Caucasian subjects: a randomized controlled cross-over clinical trial.
abstract: BACKGROUND
  Walnut consumption is associated with reduced risk of coronary heart disease (CHD).
  
  
  OBJECTIVE
  We assessed the effect of walnuts on lipid and glucose metabolism, adipokines, inflammation and endothelial function in healthy Caucasian men and postmenopausal women ≥50years old.
  
  
  METHODS
  Forty subjects (mean±SEM: age 60±1years, BMI 24.9±0.6kg/m(2); 30 females) were included in a controlled, cross-over study and randomized to receive first a walnut-enriched (43g/d) and then a Western-type (control) diet or vice-versa, with each lasting 8weeks and separated by a 2-week wash-out. At the beginning and end of each diet phase, measurements of fasting values, a mixed meal test and an assessment of postprandial endothelial function (determination of microcirculation by peripheral artery tonometry) were conducted. Area under the curve (AUC), incremental AUC (iAUC) and treatment×time interaction (shape of the curve) were evaluated for postprandial triglycerides, VLDL-triglycerides, chylomicron-triglycerides, glucose and insulin.
  
  
  RESULTS
  Compared with the control diet, the walnut diet significantly reduced non-HDL-cholesterol (walnut vs. control: -10±3 vs. -3±2mg/dL; p=0.025) and apolipoprotein-B (-5.0±1.3 vs. -0.2±1.1mg/dL; p=0.009) after adjusting for age, gender, BMI and diet sequence. Total cholesterol showed a trend toward reduction (p=0.073). Fasting VLDL-cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides and glucose, insulin, HOMA-IR, and HbA1c did not change significantly. Similarly, fasting adipokines, C-reactive protein, biomarkers of endothelial dysfunction, postprandial lipid and glucose metabolism and endothelial function were unaffected.
  
  
  CONCLUSIONS
  Daily consumption of 43g of walnuts for 8weeks significantly reduced non-HDL-cholesterol and apolipoprotein-B, which may explain in part the epidemiological observation that regular walnut consumption decreases CHD risk.
authors.affiliation: Division of Endocrinology and Metabolism at Medical Department 2, University of Munich Medical Center, Munich, Germany.
authors.forename: Liya
authors.initials: L
authors.lastname: Wu
authors.affiliation: Division of Endocrinology and Metabolism at Medical Department 2, University of Munich Medical Center, Munich, Germany.
authors.forename: Katja
authors.initials: K
authors.lastname: Piotrowski
authors.affiliation: Division of Endocrinology and Metabolism at Medical Department 2, University of Munich Medical Center, Munich, Germany.
authors.forename: Tiina
authors.initials: T
authors.lastname: Rau
authors.affiliation: Division of Endocrinology and Metabolism at Medical Department 2, University of Munich Medical Center, Munich, Germany.
authors.forename: Elisa
authors.initials: E
authors.lastname: Waldmann
authors.affiliation: Division of Endocrinology and Metabolism at Medical Department 2, University of Munich Medical Center, Munich, Germany.
authors.forename: Uli C
authors.initials: UC
authors.lastname: Broedl
authors.affiliation: Division of Metabolic and Nutritional Medicine at Dr. von Hauner Children's Hospital, University of Munich Medical Center, Munich, Germany.
authors.forename: Hans
authors.initials: H
authors.lastname: Demmelmair
authors.affiliation: Division of Metabolic and Nutritional Medicine at Dr. von Hauner Children's Hospital, University of Munich Medical Center, Munich, Germany.
authors.forename: Berthold
authors.initials: B
authors.lastname: Koletzko
authors.affiliation: Helmholtz Zentrum Muenchen, Institute for Health Economics and Healthcare Management, Neuherberg, Germany.
authors.forename: Renee G
authors.initials: RG
authors.lastname: Stark
authors.affiliation: Division of Endocrinology and Metabolism at Medical Department 2, University of Munich Medical Center, Munich, Germany.
authors.forename: Jutta M
authors.initials: JM
authors.lastname: Nagel
authors.affiliation: Division of Endocrinology, Diabetes, and Metabolism at Beth Israel Deaconess Medical Center, Boston, MA, USA.
authors.forename: Christos S
authors.initials: CS
authors.lastname: Mantzoros
authors.affiliation: Division of Endocrinology and Metabolism at Medical Department 2, University of Munich Medical Center, Munich, Germany. Electronic address: klaus.parhofer@med.uni-muenchen.de.
authors.forename: Klaus G
authors.initials: KG
authors.lastname: Parhofer
mesh_terms: D054392:Adipokines / Q000097:blood; D001055:Apolipoproteins B / Q000097:blood*; D002097:C-Reactive Protein / Q000378:metabolism; D008076:Cholesterol, HDL / Q000097:blood*; D008078:Cholesterol, LDL / Q000097:blood*; D015243:Cholesterol, VLDL / Q000097:blood*; D002914:Chylomicrons / Q000378:metabolism; D018592:Cross-Over Studies; D004032:Diet / Q000379:methods; D004727:Endothelium / Q000378:metabolism; D005215:Fasting; D005260:Female; D005947:Glucose / Q000378:metabolism; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007249:Inflammation / Q000097:blood / Q000378:metabolism; D007328:Insulin / Q000097:blood; D031324:Juglans; D050356:Lipid Metabolism / Q000502:physiology*; D008079:Lipoproteins, VLDL / Q000097:blood; D008297:Male; D008875:Middle Aged; D019518:Postprandial Period / Q000502:physiology; D011446:Prospective Studies; D014280:Triglycerides / Q000097:blood*; D044465:White People
chemical_list: D054392:Adipokines; D001055:Apolipoproteins B; D002097:C-Reactive Protein; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D015243:Cholesterol, VLDL; D002914:Chylomicrons; D005947:Glucose; D006442:Glycated Hemoglobin; D007328:Insulin; D008079:Lipoproteins, VLDL; D014280:Triglycerides; C517652:hemoglobin A1c protein, human; C030106:very low density lipoprotein triglyceride
keywords: Endothelial function; Glucose; Lipids; Nuts; Peripheral artery tonometry