Eating food fried in olive or sunflower oil is not linked to heart disease or premature death, a study has found. Here is the BMJ's editorial on the findings:

In the early 1970s, accumulating evidence showed remarkably low rates of coronary heart disease in various Mediterranean countries, where fat consumption was fairly high but olive oil was the dominant source of dietary fat.

The consumption of fried foods was not associated with the risk of coronary heart disease during the 12 year follow-up. After adjustment for a large number of potential confounding factors, the hazard ratio of coronary heart disease for frequent versus infrequent intake of fried food was 1.08 (95% confidence interval 0.82 to 1.43).

Existing data about the association between consumption of fried food and the risk of coronary heart disease are sparse and the findings inconsistent. A case-control study from Costa Rica comprising 485 cases and 508 controls also reported that frequent intake of fried foods was unrelated to myocardial infarction (odds ratio 1.06, 0.59 to 1.91)

However, the intake of fried foods can also have beneficial effects on cardiovascular risk factors. For example, a study from Italy reported that—compared with the simple addition of raw extra virgin olive oil to a mixed meal—frying food in extra virgin olive oil improved post-prandial insulin and C peptide responses in obese insulin resistant women.

http://www.telegraph.co.uk/health/healthnews/9037870/Commentary-fried-food-may-not-be-all-bad.html