© Photos.comA bacon in a day keeps the doctor away
Bacon grease - or lard - was once a mainstay in old-fashioned, country kitchens. While there are those purists out there who insist on using it to bake their biscuits or cook their beans, many who are looking to clean up their diet have been switching to vegetable fats. In fact, it's long been believed that replacing these animal fats is a heart healthier option. The American Heart Association (AHA), for example, favors replacing these saturated fats with vegetable fats of the omega-6, polyunsaturated variety.

New analysis of these beliefs, however, has found that these recommendations may have been "misguided."

In reconsidering these claims, researchers studied the cases of 458 men who had experienced a coronary event, such as a heart attack. Of these men, 16 percent who had replaced animal fats with omega-6 polyunsaturated fats found in corn, sunflower and safflower oil died from heart disease. In contrast, only 10 percent of those who did not substitute their fats died as a result of a coronary event.

Dietitians have been recommending people replace their saturated fat with oils rich in polyunsaturated fatty acids for half a century. Health authorities around the world have even suggested increasing the amount of omega-6 polyunsaturated fats in order to stave off heart disease and avoid coronary events.

Yet, there were those that disagreed with this thinking as there had not been enough solid evidence to prove that these vegetable fats reduce the risk of heart disease. Now, new analysis on this matter is the most in-depth study into the effects of these fats on those with heart disease.

This study is only now possible because randomized data gathered over a 7-year span by the Sydney Heart Study has recently been recovered.

Researchers from Australia and the US have taken a deeper look at this data, using modern statistical methods to compare the death rates from cardiac and coronary diseases.

In order to prove these results, the research team conducted a study on those 458 men, all aged between 30 and 59 years old. These men were then separated into 2 groups - those who had been told to switch from saturated fats to polyunsaturated fats and those who had not been given any dietary advice. Those who had been instructed to switch their fats had a higher death rate than those who had not been instructed to change their diet.

With this study completed, the researchers are now questioning the validity of switching from animal fat to vegetable oils.

According to the team of international researchers, finding this missing data "filled a critical gap in the published literature archive." They've also said their new research "could have important implications for worldwide dietary advice to substitute omega-6 linoleic acid (or polyunsaturated fatty acids in general) for saturated fatty acids."

Writing in an accompanying editorial, Professor Philip Calder from the University of Southampton agrees with the researchers, saying this new data "provides important information about the impact of high intakes of omega 6 PUFAs, in particular linoleic acid, on cardiovascular mortality at a time when there is considerable debate on this question."

In addition to releasing their results, the research team is also releasing the missing data they uncovered as a part of their "open data" campaign as well as asking other researchers to submit any other data which may have previously been missing.