title: Soy food consumption does not lower LDL cholesterol in either equol or nonequol producers.
abstract: BACKGROUND
  Health claims link soy protein (SP) consumption, through plasma cholesterol reduction, to a decreased risk of heart disease. Soy isoflavones (ISOs), particularly in individuals who produce equol, might also contribute to lipid lowering and thus reduce SP requirements.
  
  
  OBJECTIVE
  The objective was to examine the contributions of SP, ISOs, and equol to the hypocholesterolemic effects of soy foods.
  
  
  METHODS
  Nonsoy consumers (33 men, 58 women) with a plasma total cholesterol (TChol) concentration >5.5 mmol/L participated in a double-blind, placebo-controlled, crossover intervention trial. The subjects consumed 3 diets for 6 wk each in random order, which consisted of foods providing a daily dose of 1) 24 g SP and 70-80 mg ISOs (diet S); 2) 12 g SP, 12 g dairy protein (DP), and 70-80 mg ISOs (diet SD); and 3) 24 g DP without ISOs (diet D). Fasting plasma TChol, LDL cholesterol, HDL cholesterol, and triglycerides (TGs) were measured after each diet.
  
  
  RESULTS
  TChol was 3% lower with the S diet (-0.17 +/- 0.06 mmol/L; P < 0.05) than with the D diet, and TGs were 4% lower with both the S (-0.14 +/- 0.05 mmol/L; P < 0.05) and SD (-0.12 +/- 0.05 mmol/L; P < 0.05) diets. There were no significant effects on LDL cholesterol, HDL cholesterol, or the TChol:HDL cholesterol ratio. On the basis of urinary ISOs, 30 subjects were equol producers. Lipids were not affected significantly by equol production.
  
  
  CONCLUSIONS
  Regular consumption of foods providing 24 g SP/d from ISOs had no significant effect on plasma LDL cholesterol in mildly hypercholesterolemic subjects, regardless of equol-producing status.
authors.affiliation: Australian Technology Network Centre for Metabolic Fitness and Nutritional Physiology Research Centre, University of South Australia, South Australia, Australia.
authors.forename: Alicia A
authors.initials: AA
authors.lastname: Thorp
authors.forename: Peter R C
authors.initials: PR
authors.lastname: Howe
authors.forename: Trevor A
authors.initials: TA
authors.lastname: Mori
authors.forename: Alison M
authors.initials: AM
authors.lastname: Coates
authors.forename: Jonathan D
authors.initials: JD
authors.lastname: Buckley
authors.forename: Jonathan
authors.initials: J
authors.lastname: Hodgson
authors.forename: Jackie
authors.initials: J
authors.lastname: Mansour
authors.forename: Barbara J
authors.initials: BJ
authors.lastname: Meyer
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood / Q000378:metabolism / Q000652:urine; D002784:Cholesterol / Q000097:blood*; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood*; D018592:Cross-Over Studies; D004311:Double-Blind Method; D060754:Equol; D005260:Female; D006801:Humans; D006937:Hypercholesterolemia / Q000097:blood / Q000178:diet therapy* / Q000378:metabolism; D007529:Isoflavones / Q000008:administration & dosage* / Q000378:metabolism / Q000652:urine; D008297:Male; D008875:Middle Aged; D045730:Soy Foods / Q000032:analysis; D030262:Soybean Proteins / Q000008:administration & dosage* / Q000378:metabolism; D014280:Triglycerides / Q000097:blood
chemical_list: C007610:4',7-dihydroxy-3,4-dihydroisoflavone; D015415:Biomarkers; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D007529:Isoflavones; D030262:Soybean Proteins; D014280:Triglycerides; D060754:Equol; D002784:Cholesterol