title: Plasma and urine betaine and dimethylglycine variation in healthy young male subjects.
abstract: OBJECTIVE
  We aimed to compare the individuality (within subject consistency) of plasma and urine betaine and N,N-dimethylglycine.
  
  
  METHODS
  In two separate groups of 8 males (ages 19 to 40), plasma (10) and urine (6) samples were collected either over a single day or over an 8 week period. The individuality of the betaine and N,N-dimethylglycine plasma concentrations and excretions were estimated by one-way repeated measures analysis of variance. The reliability coefficients and indices of individuality were calculated. The between-subject variation in the study population was compared with that in a normal population (n=192 for plasma, 205 for urine).
  
  
  RESULTS
  Plasma betaine concentrations were significantly different between subjects over 24 h and 8 weeks (p<0.00001). Plasma dimethylglycine concentrations were different over 24 h. Urine betaine and dimethylglycine excretions were different in both (p<0.0001). Betaine was more individual than dimethylglycine in both plasma and urine. Compared with a normal healthy population, the between-subject variation in plasma betaine was less (p<0.001) in the study group, but similar for dimethylglycine and for urine betaine.
  
  
  CONCLUSIONS
  Plasma betaine and urinary betaine excretions are more individual than dimethylglycine. Plasma and urine betaine are highly individual in the general population.
authors.affiliation: Biochemistry Unit, Canterbury Health Laboratories, Christchurch, New Zealand. michael.lever@chmeds.ac.nz
authors.forename: Michael
authors.initials: M
authors.lastname: Lever
authors.forename: Wendy
authors.initials: W
authors.lastname: Atkinson
authors.forename: Sandy
authors.initials: S
authors.lastname: Slow
authors.forename: Stephen T
authors.initials: ST
authors.lastname: Chambers
authors.forename: Peter M
authors.initials: PM
authors.lastname: George
mesh_terms: D000328:Adult; D001622:Betaine / Q000008:administration & dosage / Q000097:blood* / Q000652:urine*; D002851:Chromatography, High Pressure Liquid; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D008297:Male; D012521:Sarcosine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000097:blood / Q000652:urine; D013997:Time Factors; D055815:Young Adult
chemical_list: D001622:Betaine; C025138:dimethylglycine; D012521:Sarcosine