Table 4.

Interaction between MTHFR C677T genotype, histology, and intervention to determine plasma 5MeTHF

Intervention*CT and TT
CC
Normal
Polyp
Normal
Polyp
MeanSEnMeanSEnMeanSEnMeanSEn
Placebo48.99.71137.79.41133.812.2757.011.19
Low folate79.29.91065.57.81688.410.01093.69.511
Low folate + riboflavin§75.48.71387.67.21987.99.21377.713.06
High folate89.99.611127.6**8.814130.0**10.013110.18.814
  • * Plasma 5MeTHF increased in the low folate groups, irrespective of genotype or histology (P < 0.001).

  • CC, CT, and TT are genotypes for the MTHFR C677T polymorphism.

  • 400 μg of folic acid daily.

  • § 400 μg of folic acid plus 5 mg of riboflavin.

  • This group showed a significant increase in plasma 5MeTHF compared with the low folic acid, no riboflavin group (P = 0.018).

  • 1,200 μg of folic acid daily.

  • ** These groups showed a significant increase in plasma 5MeTHF compared with the low-dose folic acid group (P < 0.01).