2 Supported by grant NO2035 from the Food Standard Agency and funding from the Scottish Government (Rural and Environment Research and Analysis Directorate; to GD and SD). Oat cakes were kindly provided by Paterson Arran Ltd, Livingston, United Kingdom.

3 Address reprint requests and correspondence to F Thies, Medical School, University of Aberdeen, Polwarth Building, Foresterhill, Aberdeen AB252ZD, United Kingdom. E-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it .

Background: Three daily portions of whole-grain foods could lower cardiovascular disease risk, but a comprehensive intervention trial was needed to confirm this recommendation.

Objectives: We aimed to assess the effects of consumption of 3 daily portions of whole-grain foods (provided as only wheat or a mixture of wheat and oats) on markers of cardiovascular disease risk in relatively high-risk individuals.

Design: This was a randomized controlled dietary trial in middle-aged healthy individuals. After a 4-wk run-in period on a refined diet, we randomly allocated volunteers to a control (refined diet), wheat, or wheat + oats group for 12 wk. The primary outcome was a reduction of cardiovascular disease risk factors by dietary intervention with whole grains, which included lipid and inflammatory marker concentrations, insulin sensitivity, and blood pressure.

Results: We recruited a total of 233 volunteers; 24 volunteers withdrew and 3 volunteers were excluded. Systolic blood pressure and pulse pressure were significantly reduced by 6 and 3 mm Hg, respectively, in the whole-grain foods groups compared with the control group. Systemic markers of cardiovascular disease risk remained unchanged apart from cholesterol concentrations, which decreased slightly but significantly in the refined group.

Conclusions: Daily consumption of 3 portions of whole-grain foods can significantly reduce cardiovascular disease risk in middle-aged people mainly through blood pressure–lowering mechanisms. The observed decrease in systolic blood pressure could decrease the incidence of coronary artery disease and stroke by ge 15% and 25%, respectively. This trial was registered at clinicaltrials.gov as ISRCTN27657880.