Betaine and folate status as cooperative determinants of plasma homocysteine in humans

Holm PI, Ueland PM, Vollset SE, et al. · Arteriosclerosis, Thrombosis, and Vascular Biology

Why betaine and folate are not interchangeable: plasma betaine was the strongest determinant of the homocysteine rise after a methionine load, folate the stronger determinant of fasting homocysteine, and betaine's effect was most pronounced in people with low folate status.

Population

Healthy men and women aged 34-69, fasting and 6 hours after a standard methionine load

Intervention

Plasma betaine, folate, vitamin B6 and related metabolites measured; no supplement given

Comparator

Across the range of folate status

Limitations

Observational cross-sectional design with a metabolic challenge; describes determinants of a biomarker, not the effect of supplementing anything.