title: Effects of soy isoflavones and phytate on homocysteine, C-reactive protein, and iron status in postmenopausal women.
abstract: BACKGROUND
  Soy protein or its components may protect against the atherosclerotic cardiovascular disease (CVD) risk factors total homocysteine (tHcy), C-reactive protein (CRP), and excess body iron, which generally increase with menopause.
  
  
  OBJECTIVE
  The primary objective of this study was to determine the independent effect of the soy protein components isoflavones and phytate on CVD risk factors in postmenopausal women. The secondary objective was to identify factors [blood lipids, oxidative stress indexes, serum ferritin, plasma folate, plasma vitamin B-12, and body mass index (BMI)] contributing to tHcy and CRP concentrations.
  
  
  METHODS
  In a double-blind, 6-wk study, 55 postmenopausal women aged 47-72 y were randomly assigned to 1 of 4 soy protein (40 g/d) isolate treatments: native phytate and native isoflavone (n = 14), native phytate and low isoflavone (n = 13), low phytate and native isoflavone (n = 14), or low phytate and low isoflavone (n = 14). We measured iron indexes, tHcy, CRP, and BMI.
  
  
  RESULTS
  Soy protein with native phytate significantly reduced tHcy (P = 0.017), transferrin saturation (P = 0.027), and ferritin (P = 0.029), whereas soy protein with native isoflavones had no effect on any variables. At baseline, BMI was highly correlated with tHcy (r = 0.39, P = 0.003) and CRP (r = 0.55, P < 0.0001), whereas HDL cholesterol was correlated with CRP (r = -0.30, P = 0.02). Multiple regression analysis showed that LDL cholesterol and BMI contributed significantly (R2= 19.9%, P = 0.003) to the overall variance in tHcy.
  
  
  CONCLUSIONS
  Consuming phytate-rich foods and maintaining a healthy weight may reduce atherosclerotic CVD risk factors in postmenopausal women.
authors.affiliation: Department of Food Science and Human Nutrition, Iowa State University, Ames, IA 50011, USA.
authors.forename: Laura N
authors.initials: LN
authors.lastname: Hanson
authors.forename: Heather M
authors.initials: HM
authors.lastname: Engelman
authors.forename: D Lee
authors.initials: DL
authors.lastname: Alekel
authors.forename: Kevin L
authors.initials: KL
authors.lastname: Schalinske
authors.forename: Marian L
authors.initials: ML
authors.lastname: Kohut
authors.forename: Manju B
authors.initials: MB
authors.lastname: Reddy
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000378:metabolism*; D003324:Coronary Artery Disease / Q000097:blood* / Q000209:etiology / Q000517:prevention & control; D004311:Double-Blind Method; D005260:Female; D005293:Ferritins / Q000097:blood; D005492:Folic Acid / Q000097:blood; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D007501:Iron / Q000378:metabolism*; D007529:Isoflavones / Q000494:pharmacology*; D008055:Lipids / Q000097:blood; D008875:Middle Aged; D018384:Oxidative Stress; D010833:Phytic Acid / Q000494:pharmacology*; D014674:Plant Proteins, Dietary / Q000494:pharmacology; D017698:Postmenopause / Q000097:blood*; D012044:Regression Analysis; D012307:Risk Factors; D030262:Soybean Proteins / Q000494:pharmacology*; D014168:Transferrin / Q000378:metabolism; D014805:Vitamin B 12 / Q000097:blood
chemical_list: D015415:Biomarkers; D007529:Isoflavones; D008055:Lipids; D014674:Plant Proteins, Dietary; D030262:Soybean Proteins; D014168:Transferrin; D006710:Homocysteine; D010833:Phytic Acid; D002097:C-Reactive Protein; D005293:Ferritins; D005492:Folic Acid; D007501:Iron; D014805:Vitamin B 12