Background & Aims: At least 500 mug of folic acid are required daily to treat hyperhomocysteinemia. To reach this amount by dietary changes alone may be difficult because food has a low folic acid content and bioavailability. No studies have compared the effects of similar amounts of additional folate derived from a combination of folate-rich and fortified foods or folic acid from supplements on plasma total homocysteine (tHcy) concentrations, which was the aim of this study. Methods: Twenty male patients with hyperhomocysteinemia and coronary artery disease were included in a randomized, crossover intervention trial. Patients were treated daily with a combination of foods containing approximately 500 mug of folate or with one 500 mug capsule of synthetic folic acid over two five-week periods separated by a five-week wash-out period. Results: Plasma folate increased markedly (p<0.001) and plasma tHcy decreased (p<0.001) with both therapies. Folate-rich foods decreased tHcy by 8.6% (95% CI: -15.9 to -1.2) and synthetic folic acid capsules by 8% (95% CI: -13.3 to -2.7). Conclusions: This study shows, for the first time in the literature, that a folate-rich diet is as effective as folic acid capsules in decreasing plasma tHcy concentrations and adds further support to the recommendation of those diets to prevent cardiovascular disease.