title: Cumulative consumption of branched-chain amino acids and incidence of type 2 diabetes.
abstract: Plasma branched-chain amino acids (BCAAs, including leucine, isoleucine and valine) were recently related to risk of type 2 diabetes (T2D). Dietary intake is the only source of BCAAs; however, little is known about whether habitual dietary intake of BCAAs affects risk of T2D.
  
  
  
  We assessed associations between cumulative consumption of BCAAs and risk of T2D among participants from three prospective cohorts: the Nurses' Health Study (NHS; followed from 1980 to 2012); NHS II (followed from 1991 to 2011); and the Health Professionals Follow-up Study (HPFS; followed from 1986 to 2010).
  
  
  
  We documented 16 097 incident T2D events during up to 32 years of follow-up. After adjustment for demographics and traditional risk factors, higher total BCAA intake was associated with an increased risk of T2D in men and women. In the meta-analysis of all cohorts, comparing participants in the highest quintile with those in the lowest quintile of intake, hazard ratios (95%confidence intervals) were for leucine 1.13 (1.07-1.19), for isoleucine 1.13 (1.07-1.19) and for valine 1.11 (1.05-1.17) (all P for trend < 0.001). In a healthy subsample, higher dietary BCAAs were significantly associated with higher plasma levels of these amino acids (P for trend = 0.01).
  
  
  
  Our data suggest that high consumption of BCAAs is associated with an increased risk of T2D.
authors.affiliation: Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
authors.forename: Yan
authors.initials: Y
authors.lastname: Zheng
authors.affiliation: Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
authors.forename: Yanping
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Epidemiology & Population Health, Albert Einstein College of Medicine, Bronx, NY, USA.
authors.forename: Qibin
authors.initials: Q
authors.lastname: Qi
authors.affiliation: Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
authors.forename: Adela
authors.initials: A
authors.lastname: Hruby
authors.affiliation: Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.|Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA.|Division of Preventive Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, MA, USA.
authors.forename: JoAnn E
authors.initials: JE
authors.lastname: Manson
authors.affiliation: Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA, USA.|Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.|Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
authors.forename: Walter C
authors.initials: WC
authors.lastname: Willett
authors.affiliation: Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA, USA.
authors.forename: Brian M
authors.initials: BM
authors.lastname: Wolpin
authors.affiliation: Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA, USA.|Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.|Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
authors.forename: Frank B
authors.initials: FB
authors.lastname: Hu
authors.affiliation: Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA, USA lqi1@tulane.edu.|Department of Epidemiology, School of Public Health and Tropical Medicine, Tulane University, New Orleans, LA, USA.
authors.forename: Lu
authors.initials: L
authors.lastname: Qi
mesh_terms: D000328:Adult; D000368:Aged; D000597:Amino Acids, Branched-Chain / Q000008:administration & dosage*; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology*; D004032:Diet; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011446:Prospective Studies; D012307:Risk Factors; D014481:United States
chemical_list: D000597:Amino Acids, Branched-Chain
keywords: Diet; branched-chain amino acids; cohort study; type 2 diabetes