The Glu298Asp polymorphism has been linked to increased risk of cardiovascular events, proposed to be due to reduced nitric oxide production by eNOS reported in some but not all studies. We hypothesise that beetroot-enriched bread interacts with the Glu298Asp polymorphism of the eNOS gene to lower blood pressure and increase plasma nitrate/nitrite, particularly in carriers of the T allele, which have been associated with lower eNOS activity and increased risk of hypertension.