Donut eat them (Image: Roy Ooms/Getty)

Here’s something to chew over. Eating more trans fats is linked to coronary heart disease, while eating saturated fats is not. That’s according to an analysis of 123 studies of dietary fat and cardiovascular health.

Most dietary advice recommends limiting the consumption of saturated fats, which are found in butter, milk, meat and egg, due to the risk of developing heart disease. But Russell de Souza of McMaster University in Ontario, Canada, and his team were unable to find a clear association between these fats and the chances of heart or cardiovascular disease.

This wasn’t the case with industrial trans fats, which are made by hydrogenating plant oils and are found in margarine and some processed foods like cake. The analysis suggests that eating more trans fat is associated with a 21 per cent rise in the likelihood of developing heart disease, and a 28 per cent rise in the risk of dying of this condition, confirming a number of other reviews that have linked trans fats to heart disease.


Earlier this year, the US Food and Drug Administration banned the use of trans fats in food, giving manufacturers three years to comply.

“The results of this review support existing guidance to avoid industrially produced trans fats,” said Victoria Taylor, a dietician for the British Heart Foundation charity. “In the UK, industry action to remove these fats from manufactured foods means that our intakes are already below the recommended maximum of 2 per cent of food energy.”

The UK also advises that saturated fat makes up no more than 11 per cent of a person’s daily energy intake.

But de Souza’s results don’t necessarily mean it’s time to scrap this recommendation just yet. Although they were unable to find a link in their analysis, it is still possible that there might be one. Furthermore, sources of saturated fat may pose other health risks, says de Souza.

“There are many factors which cause coronary heart disease and no single food or nutrient is solely responsible for this,” said Taylor. “We will continue to recommend switching saturated fat for unsaturated fat, consistent with a traditional Mediterranean-style diet.”

Journal reference: BMJ, DOI: 10.1136/bmj.h3978.