title: Effects of lutein-enriched egg yolk in buttermilk or skimmed milk on serum lipids & lipoproteins of mildly hypercholesterolemic subjects.
abstract: OBJECTIVE
  Earlier studies in our group suggested that traditionally prepared buttermilk influences cholesterol metabolism. We therefore designed a study to evaluate whether traditionally prepared buttermilk lowers serum low-density lipoprotein cholesterol (LDL-C) and/or prevents the LDL-C raising effect of egg yolks.
  
  
  RESULTS
  Mildly hypercholesterolemic subjects were randomly allocated to one of four diet groups consuming daily at lunch 80 ml skimmed milk with (n = 23) or without (n = 25) lutein-enriched egg yolk (28 g from 1.5 eggs providing 323 mg cholesterol) or traditionally prepared buttermilk with (n = 23) or without (n = 21) lutein-enriched egg yolk during a 12 week period. Fasting blood samples were taken to measure concentrations of serum lipids, (apo)lipoproteins, liver and kidney function markers, and plasma lutein, zeaxanthin and high-sensitive C-reactive protein (hsCRP). Egg yolk consumption significantly increased serum total cholesterol (total-C) (p = 0.035) and LDL-C concentrations (p = 0.022). Buttermilk did not change the effects of egg yolk on serum lipids and (apo)lipoproteins. There was a trend towards significant lower total-C (p = 0.077), but not LDL-C (p = 0.204) concentrations in the buttermilk groups. Plasma lutein and zeaxanthin concentrations increased significantly (p < 0.001) in the egg yolk groups.
  
  
  CONCLUSIONS
  In mildly hypercholesterolemic subjects, daily consumption of traditionally prepared buttermilk for 12 weeks did not lower serum total-C or LDL-C concentrations, nor did it prevent the serum total-C and LDL-C raising effect of daily egg yolk consumption.
  
  
  BACKGROUND
  This study is registered at www.clinicaltrials.gov as NCT01566305.
authors.affiliation: NUTRIM School for Nutrition, Toxicology and Metabolism, Department of Human Biology, Maastricht University, The Netherlands.
authors.forename: N
authors.initials: N
authors.lastname: Severins
authors.affiliation: NUTRIM School for Nutrition, Toxicology and Metabolism, Department of Human Biology, Maastricht University, The Netherlands.
authors.forename: R P
authors.initials: RP
authors.lastname: Mensink
authors.affiliation: NUTRIM School for Nutrition, Toxicology and Metabolism, Department of Human Biology, Maastricht University, The Netherlands. Electronic address: j.plat@maastrichtuniversity.nl.
authors.forename: J
authors.initials: J
authors.lastname: Plat
mesh_terms: D000368:Aged; D000818:Animals; D015415:Biomarkers / Q000097:blood; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000378:metabolism; D002784:Cholesterol / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D043302:Cultured Milk Products / Q000737:chemistry*; D004040:Dietary Carbohydrates / Q000008:administration & dosage; D004041:Dietary Fats / Q000008:administration & dosage; D004530:Egg Yolk / Q000737:chemistry*; D005215:Fasting; D005227:Fatty Acids / Q000008:administration & dosage; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D006937:Hypercholesterolemia / Q000097:blood*; D014975:Lutein / Q000008:administration & dosage* / Q000097:blood; D008297:Male; D008875:Middle Aged; D065146:Zeaxanthins / Q000097:blood
chemical_list: D015415:Biomarkers; D008078:Cholesterol, LDL; D004040:Dietary Carbohydrates; D004041:Dietary Fats; D005227:Fatty Acids; D065146:Zeaxanthins; D002097:C-Reactive Protein; D002784:Cholesterol; D014975:Lutein
keywords: Buttermilk; Cholesterol; Egg yolk; Lutein; Milk polar lipids; Serum lipids; Zeaxanthin