title: Effects of long-term selenium supplementation on the incidence of type 2 diabetes: a randomized trial.
abstract: BACKGROUND
  Findings from animal models suggest that selenium supplementation improves glucose metabolism.
  
  
  OBJECTIVE
  To examine the effect of long-term selenium supplementation on the incidence of type 2 diabetes.
  
  
  METHODS
  Secondary analysis of a randomized, double-blind, placebo-controlled trial.
  
  
  METHODS
  Areas of low selenium consumption of the eastern United States.
  
  
  METHODS
  1202 persons seen in dermatology clinics who did not have type 2 diabetes at baseline.
  
  
  METHODS
  Oral administration of selenium, 200 microg/d, or placebo.
  
  
  METHODS
  Incidence of type 2 diabetes.
  
  
  RESULTS
  During an average follow-up of 7.7 years (SD, 2.7), type 2 diabetes developed in 58 selenium recipients and 39 placebo recipients (incidence, 12.6 cases per 1000 person-years vs. 8.4 cases per 1000 person-years, respectively; hazard ratio, 1.55 [95% CI, 1.03 to 2.33]). The lack of benefit of selenium supplementation on the incidence of type 2 diabetes persisted in analyses stratified by age, sex, body mass index, and smoking status. An exposure-response gradient was found across tertiles of baseline plasma selenium level, with a statistically significantly increased risk for type 2 diabetes in the highest tertile of baseline plasma selenium level (hazard ratio, 2.70 [CI, 1.30 to 5.61]).
  
  
  CONCLUSIONS
  Diabetes was a secondary outcome in the parent trial. Diagnoses of diabetes were self-reported but were validated in most participants. The sample was mostly older and white.
  
  
  CONCLUSIONS
  Selenium supplementation does not seem to prevent type 2 diabetes, and it may increase risk for the disease. Click here for related information on selenium.
authors.affiliation: State University of New York at Buffalo and Cancer Prevention and Population Sciences, Roswell Park Cancer Institute, Buffalo, New York, USA. s.stranges@warwick.ac.uk
authors.forename: Saverio
authors.initials: S
authors.lastname: Stranges
authors.forename: James R
authors.initials: JR
authors.lastname: Marshall
authors.forename: Raj
authors.initials: R
authors.lastname: Natarajan
authors.forename: Richard P
authors.initials: RP
authors.lastname: Donahue
authors.forename: Maurizio
authors.initials: M
authors.lastname: Trevisan
authors.forename: Gerald F
authors.initials: GF
authors.lastname: Combs
authors.forename: Francesco P
authors.initials: FP
authors.lastname: Cappuccio
authors.forename: Antonio
authors.initials: A
authors.lastname: Ceriello
authors.forename: Mary E
authors.initials: ME
authors.lastname: Reid
mesh_terms: D000368:Aged; D000975:Antioxidants / Q000008:administration & dosage* / Q000009:adverse effects / Q000378:metabolism; D001786:Blood Glucose / Q000378:metabolism; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000453:epidemiology / Q000517:prevention & control*; D019587:Dietary Supplements / Q000009:adverse effects; D004311:Double-Blind Method; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012643:Selenium / Q000008:administration & dosage* / Q000009:adverse effects / Q000097:blood; D013997:Time Factors; D014481:United States
chemical_list: D000975:Antioxidants; D001786:Blood Glucose; D012643:Selenium