Hypertension is a leading risk factor for cardiovascular disease (CVD) and stroke. A common polymorphism in the gene encoding the enzyme methylenetetrahydrofolate reductase (MTHFR), previously identified as the main genetic determinant of elevated homocysteine concentration and also recognized as a risk factor for CVD, appears to be independently associated with hypertension. The B-vitamin riboflavin is required as a cofactor by MTHFR and recent evidence suggests it may have a role in modulating blood pressure, specifically in those with the homozygous mutant MTHFR 677 TT genotype. If studies confirm that this genetic predisposition to hypertension is correctable by low-dose riboflavin, the findings could have important implications for the management of hypertension given that the frequency of this polymorphism ranges from 3 to 32 % worldwide.