Trans fats u2014 used in margarine, snack foods and packaged baked goods u2014 may increase a person’s risk for heart disease and mortality, new research has claimed.
Saturated fats are not associated with an increased risk of death, heart disease, stroke, or type 2 diabetes, researchers found.
However, the findings show that trans fats are associated with greater risk of death and coronary heart disease, they said.
The study by researchers at several Canadian institutions including McMaster University in Ontario, confirms previous suggestions that industrially produced trans fats might increase the risk of coronary heart disease and calls for a careful review of dietary guidelines for these nutrients.
Guidelines currently recommend that saturated fats are limited to less than 10 per cent, and trans fats to less than one per cent of energy to reduce risk of heart disease and stroke.
Saturated fats come mainly from animal products, such as butter, cows’ milk, meat, salmon and egg yolks, and some plant products such as chocolate and palm oils.
Trans unsaturated fats (trans fats) are mainly produced industrially from plant oils (a process known as hydrogenation) for use in margarine, snack foods and packaged baked goods.
Contrary to prevailing dietary advice, a recent evidence review found no excess cardiovascular risk associated with intake of saturated fat.
In contrast, research suggests that industrial trans fats may increase the risk of coronary heart disease.
To help clarify these controversies, researchers in Canada analysed the results of observational studies assessing the association between saturated and/or trans fats and health outcomes in adults.
The team found no clear association between higher intake of saturated fats and all cause mortality, coronary heart disease (CHD), cardiovascular disease (CVD), ischemic stroke or type 2 diabetes, but could not, with confidence, rule out increased risk for CHD death.
However, consumption of industrial trans fats was associated with a 34 per cent increase in all cause mortality, a 28 per cent increased risk of CHD mortality, and a 21 per cent increase in the risk of CHD.
Inconsistencies in the included studies meant that the researchers could not confirm an association between trans fats and type 2 diabetes. And they found no clear association between trans fats and ischemic stroke.
The study was published in The BMJ.