Food fried in olive or sunflower oil is not linked to heart disease or premature death, a Spanish study has claimed.

However, research published in the British Medical Journal warns food cooked in solid or re-used oils may not be quite as harmless.

When food is fried it becomes more calorific because the food absorbs the fat of the oils, which can lead to high blood pressure, high cholesterol and obesity.

Researchers, led by Professor Pilar Guallar-Castillón from the Autonomous University of Madrid, surveyed the cooking methods of 40,757 adults aged 29 to 69 over an 11-year period. 

The participants’ diet was divided into ranges of fried food consumption.

None of the participants were believed to have heart disease when the study began, but by the end there were 606 events linked to heart disease and 1,134 deaths.

Researchers analysed the heart disease events “in detail” but found no evidence of a link with fried food.

“In a Mediterranean country where olive and sunflower oils are the most commonly used fats for frying, and where large amounts of fried foods are consumed both at and away from home, no association was observed between fried food consumption and the risk of coronary heart disease or death,” they said. 

Professor Michael Leitzmann from the University of Regensburg in Germany, said the study “explodes the myth that frying food is generally bad for the heart”.

He, however, stressed this does not mean that frequent meals of fish and chips will have “no health consequences”.