The Spanish government's health research agency initiated and paid for the study, and foods were supplied by olive oil and nut producers in Spain and the California Walnut Commission. Many of the authors have extensive financial ties to food, wine and other industry groups but said the sponsors had no role in designing the study or analyzing and reporting its results.
Rachel Johnson, a University of Vermont professor who heads the American Heart Association's nutrition committee, said the study is very strong because of the lab tests to verify oil and nut consumption and because researchers tracked actual heart attacks, strokes and deaths — not just changes in risk factors such as high cholesterol.
"At the end of the day, what we care about is whether or not disease develops," she said. "It's an important study."
