The new research was a secondary analysis of data collected for a 2011 study on the effect of the "portfolio diet" on cholesterol. The diet includes foods that are scientifically-proven to lower cholesterol including mixed nuts, soy protein, plant sterols (found in vegetable oils and leafy vegetables) and viscous fibre (found in oats, barley and eggplant).
"This is an important secondary finding to the original study, adding to the literature connecting diet with health," said Dr David Jenkins, study's lead author from St. Michael's Hospital and professor at the University of Toronto.
"We can now say the dietary portfolio is ideal for reducing overall risk of cardiovascular disease," he added.
The comparison method, a dietary approach to stopping hypertension or DASH (Dietary Approaches to Stop Hypertension) diet emphasizes fruit, vegetables and whole grains, reduced meat and dairy intake and eliminating snack food.
The modest, two percent reduction in blood pressure on the "portfolio diet" is in addition to the five to 10 mm blood pressure improvement associated with a DASH-type diet. Although DASH diet had higher compliance rates, the "portfolio diet" was more effective in reducing blood pressure.
High blood pressure and cholesterol are major risk factors for cardiovascular disease and stroke, historically treated with medications.
"Dietary approaches were found to be as effective as the starting dose of the average single blood pressure medication," Dr Jenkins added.
Overall, research has shown that plant-based diets emphasizing foods higher in protein, oil and fibre reduce the risk of cardiovascular disease and stroke.
The research appeared in the journal Nutrition, Metabolism and Cardiovascular Disease.