title: Amino Acid Intakes Are Inversely Associated with Arterial Stiffness and Central Blood Pressure in Women.
abstract: BACKGROUND
  Although data suggest that intakes of total protein and specific amino acids (AAs) reduce blood pressure, data on other cardiovascular disease risk factors are limited.
  
  
  OBJECTIVE
  We examined associations between intakes of AAs with known mechanistic links to cardiovascular health and direct measures of arterial stiffness, central blood pressure, and atherosclerosis.
  
  
  METHODS
  In a cross-sectional study of 1898 female twins aged 18-75 y from the TwinsUK registry, intakes of 7 cardioprotective AAs (arginine, cysteine, glutamic acid, glycine, histidine, leucine, and tyrosine) were calculated from food-frequency questionnaires. Direct measures of arterial stiffness and atherosclerosis included central systolic blood pressure (cSBP), mean arterial pressure (MAP), augmentation index (AI), pulse wave velocity (PWV), and intima-media thickness (IMT). ANCOVA was used to assess the associations between endpoints of arterial stiffness and intake (per quintile), adjusting for potential confounders.
  
  
  RESULTS
  In multivariable analyses, higher intakes of total protein and 7 potentially cardioprotective AAs were associated with lower cSBP, MAP, and PWV. Higher intakes of glutamic acid, leucine, and tyrosine were most strongly associated with PWV, with respective differences of -0.4 ± 0.2 m/s (P-trend = 0.02), -0.4 ± 0.2 m/s (P-trend = 0.03), and -0.4 ± 0.2 m/s (P-trend = 0.03), comparing extreme quintiles. There was a significant interaction between AA intakes and protein source, and higher intakes of AAs from vegetable sources were associated with lower central blood pressure and AI. Higher intakes of glutamic acid, leucine, and tyrosine from animal sources were associated with lower PWV.
  
  
  CONCLUSIONS
  These data provide evidence to suggest that intakes of several AAs are associated with cardiovascular benefits beyond blood pressure reduction in healthy women. The magnitude of the observed associations was similar to those previously reported for other lifestyle factors. Increasing intakes of these AAs could be an important and readily achievable way to reduce cardiovascular disease risk.
authors.affiliation: Department of Nutrition, Norwich Medical School, University of East Anglia, Norwich, United Kingdom; and.
authors.forename: Amy
authors.initials: A
authors.lastname: Jennings
authors.affiliation: Department of Nutrition, Norwich Medical School, University of East Anglia, Norwich, United Kingdom; and.
authors.forename: Alex
authors.initials: A
authors.lastname: MacGregor
authors.affiliation: Department of Nutrition, Norwich Medical School, University of East Anglia, Norwich, United Kingdom; and.
authors.forename: Ailsa
authors.initials: A
authors.lastname: Welch
authors.affiliation: Department of Twin Research and Genetic Epidemiology, King's College London, London, United Kingdom.
authors.forename: Phil
authors.initials: P
authors.lastname: Chowienczyk
authors.affiliation: Department of Twin Research and Genetic Epidemiology, King's College London, London, United Kingdom.
authors.forename: Tim
authors.initials: T
authors.lastname: Spector
authors.affiliation: Department of Nutrition, Norwich Medical School, University of East Anglia, Norwich, United Kingdom; and a.cassidy@uea.ac.uk.
authors.forename: Aedín
authors.initials: A
authors.lastname: Cassidy
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000596:Amino Acids / Q000008:administration & dosage*; D050197:Atherosclerosis / Q000453:epidemiology; D001794:Blood Pressure; D059168:Carotid Intima-Media Thickness; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008875:Middle Aged; D015999:Multivariate Analysis; D063177:Pulse Wave Analysis; D012307:Risk Factors; D006113:United Kingdom; D059289:Vascular Stiffness; D055815:Young Adult
chemical_list: D000596:Amino Acids
keywords: amino acids; arterial stiffness; blood pressure; cardiovascular; protein