Dietary and supplementary betaine: effects on betaine and homocysteine concentrations in males.
OBJECTIVE
Betaine is an osmolyte that when catabolised decreases plasma total homocysteine. A betaine-rich meal has acute effects similar to a supplement, but the effects of a longer-term increase in dietary betaine intake need clarification. We compared the effects of two weeks of dietary and supplementary betaine on plasma betaine and homocysteine concentrations both fasting and after a methionine load.


RESULTS
In a randomized crossover study, 8 healthy males (22-36 y) consumed either a betaine-rich diet ( approximately 800 mg/day) or a betaine supplement (0.5 g twice daily) for 14 days. Fasting blood samples were collected on day -5, -1 (pre-treatment) 0, 2, 6, 9, 13 (treatment), 14 and 18 (post-treatment). Post-methionine load blood samples were collected on day -5, 0, 6 and 13, while 24h urine samples were collected on day -5, 0, 6, 13 and 14. Plasma betaine, dimethylglycine, homocysteine and urine betaine, dimethylglycine and creatinine concentrations were measured. Plasma betaine concentrations significantly increased for both treatments compared to pre-treatment values (P<0.001). Fasting homocysteine levels were minimally affected. Both treatments reduced post-methionine load homocysteine and this effect tended to be greater following a betaine-rich diet (P=0.108). Small increases in urinary betaine excretion were observed following both treatments ( approximately 1.5% of supplement; approximately 1.3% of dietary betaine). Most was attributable to increased excretion of betaine as dimethylglycine.


CONCLUSIONS
Supplemental or dietary betaine similarly increase circulating betaine concentrations and attenuate the post-methionine load rise in homocysteine concentrations.
Clinical Biochemistry Unit, Canterbury Health Laboratories, P.O. Box 151, Christchurch Mail Centre, Christchurch, New Zealand.
W
W
Atkinson
S
S
Slow
J
J
Elmslie
M
M
Lever
S T
ST
Chambers
P M
PM
George
D000328:Adult; D001622:Betaine / Q000008:administration & dosage* / Q000097:blood / Q000652:urine; D015415:Biomarkers / Q000097:blood / Q000652:urine; D002794:Choline / Q000008:administration & dosage; D003404:Creatinine / Q000652:urine; D018592:Cross-Over Studies; D004032:Diet; D019587:Dietary Supplements; D005492:Folic Acid / Q000008:administration & dosage; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D008055:Lipids / Q000097:blood; D008297:Male; D012521:Sarcosine / Q000031:analogs & derivatives / Q000097:blood / Q000652:urine; D013997:Time Factors; D014805:Vitamin B 12 / Q000008:administration & dosage; D055815:Young Adult
D015415:Biomarkers; D008055:Lipids; D006710:Homocysteine; D001622:Betaine; C025138:dimethylglycine; D005492:Folic Acid; D003404:Creatinine; D002794:Choline; D014805:Vitamin B 12; D012521:Sarcosine