Vegetables, nuts, Med diet good for heart

HAMILTON, Ontario, April 14 (UPI) -- Vegetables, nuts and a Mediterranean diet are linked to lower heart risk, but trans-fats and high glycemic foods may be harmful, Canadian researchers said.

Andrew Mente of the Population Health Research Institute at McMaster University in Hamilton and colleagues conducted a systematic search for articles published from 1950 to June 2007investigating dietary factors in relation to heart disease.

A total of 146 studies that looked back on the habits and 43 randomized controlled trials -- participants randomly assigned to a dietary intervention or a control group -- were identified and included in the review.

The review, published in the Archives of Internal Medicine, identified strong evidence of a causal relationship for protective factors for those who ate vegetables, nuts, monounsaturated fatty acids and a Mediterranean diet. Harmful factors include: intake of trans-fatty acids and foods with a high glycemic index -- carbohydrates that break down rapidly during digestion releasing glucose rapidly into the bloodstream -- or a western dietary pattern.

"Taken together, these findings support a causal relationship between only a few dietary exposures and coronary heart disease, whereas the evidence for most individual nutrients or foods is too modest to be conclusive," the study authors said in a statement.