But researchers have now put a figure on it. They reckon trans fats triple your chances of heart disease.
The new study, from the Harvard School of Public Health, is the first to measure the risk from blood samples. Earlier studies based their findings on food diaries, which participants completed when they had time. Diaries are notoriously inaccurate, because people don't always like to reveal their bad eating habits, even in an anonymous study.
As the researchers explain, trans fats not only increase the levels of 'bad' LDL cholesterol levels, they also decrease the levels of HDL, or 'good', cholesterol.
The message is not lost on the fast food restaurant chains, such as MacDonalds, which are busy changing their cooking oils to a healthier mix.
(Source: Circulation, published online, March 26, 2007).
E-news broadcast 5 April 2007 No.348 [Subscribe]