TY - JOUR
T1 - Effects of riboflavin and folic acid supplementation on plasma homocysteine levels in healthy subjects
AU - Cherng, Zee Chuang
AU - Boyles, Adrienne
AU - Legardeur, Barbara
AU - Su, Joseph
AU - Japa, Shanker
AU - Lopez-S, Alfredo
PY - 2006/2
Y1 - 2006/2
N2 - Background: Observational studies have shown an inverse relationship between vitamin B2 status and total homocysteine levels, a risk factor for cardiovascular disease. We hypothesize that intervention with riboflavin will lower total homocysteine levels. The total homocysteine lowering by the three genotypes (CC, CT, TT) of methylenetetrahydrofolate reductase polymorphism (677C→T) was also studied. Methods: The decrease in total homocysteine levels after supplementation with riboflavin (10 mg/d) or folic acid (1 mg/d) for 3 weeks was compared in two groups of healthy subjects (17 per group, matched by age and gender) (Phase 1). Then, both groups received supplementation with folic acid and riboflavin for an additional 3 weeks (Phase 2). Results: During Phase 1, total homocysteine levels were lowered by 2% or 4% after supplementation with riboflavin or fatty acid, respectively, although neither decrease was statistically significant (P = 0.50 and 0.19). Compared to subjects of CC genotype, total homocysteine lowering in subjects of CT genotype was approaching significance (P = 0.059) for the folic acid group, but not for the riboflavin group. After Phase 2, total homocysteine levels were not lowered significantly in either the folic acid (1%) or the riboflavin (2%) group. However, in the folic acid-riboflavin combined group, total homocysteine lowering in subjects of TT type was larger when compared to subjects of CC and CT types (P = 0.007). Conclusions: Riboflavin supplementation did not lower total homocysteine levels in healthy subjects with CC type of C677T polymorphism. However, supplementation with folic acid or with both folic acid and riboflavin may be important for CT and TT subjects in optimizing their homocysteine metabolism. These findings are relevant in characterizing the factors controlling the high total homocysteine levels for subjects of CT and TT genotypes.
AB - Background: Observational studies have shown an inverse relationship between vitamin B2 status and total homocysteine levels, a risk factor for cardiovascular disease. We hypothesize that intervention with riboflavin will lower total homocysteine levels. The total homocysteine lowering by the three genotypes (CC, CT, TT) of methylenetetrahydrofolate reductase polymorphism (677C→T) was also studied. Methods: The decrease in total homocysteine levels after supplementation with riboflavin (10 mg/d) or folic acid (1 mg/d) for 3 weeks was compared in two groups of healthy subjects (17 per group, matched by age and gender) (Phase 1). Then, both groups received supplementation with folic acid and riboflavin for an additional 3 weeks (Phase 2). Results: During Phase 1, total homocysteine levels were lowered by 2% or 4% after supplementation with riboflavin or fatty acid, respectively, although neither decrease was statistically significant (P = 0.50 and 0.19). Compared to subjects of CC genotype, total homocysteine lowering in subjects of CT genotype was approaching significance (P = 0.059) for the folic acid group, but not for the riboflavin group. After Phase 2, total homocysteine levels were not lowered significantly in either the folic acid (1%) or the riboflavin (2%) group. However, in the folic acid-riboflavin combined group, total homocysteine lowering in subjects of TT type was larger when compared to subjects of CC and CT types (P = 0.007). Conclusions: Riboflavin supplementation did not lower total homocysteine levels in healthy subjects with CC type of C677T polymorphism. However, supplementation with folic acid or with both folic acid and riboflavin may be important for CT and TT subjects in optimizing their homocysteine metabolism. These findings are relevant in characterizing the factors controlling the high total homocysteine levels for subjects of CT and TT genotypes.
KW - Folic acid
KW - Homocysteine
KW - Intervention
KW - Methylenetetrahydrofolate reductase
KW - Riboflavin
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U2 - 10.1097/00000441-200602000-00011
DO - 10.1097/00000441-200602000-00011
M3 - Article
C2 - 16479177
AN - SCOPUS:33646100519
SN - 0002-9629
VL - 331
SP - 65
EP - 71
JO - American Journal of the Medical Sciences
JF - American Journal of the Medical Sciences
IS - 2
ER -