The demonisation of trans fats could turn people off perfectly healthy products, a leading nutrition expert warned this week.

Trans fats have earned a notorious reputation because of their link with heart disease - and many major retailers and manufacturers have pledged to remove them from products as soon as possible.

But Dr Adam Lock, assistant professor at the University of Vermont USA, said branding all trans fats as unhealthy was a mistake.

The man-made hydrogenated vegetable fats used in cakes, biscuits and confectionery, and blamed for increasing cholesterol levels and blocking arteries, were totally different to the natural trans fats found in animal products, which offered health benefits, he said.

The EU is considering mandatory labelling of products with trans fats - but current proposals do not distinguish between man-made trans fats and naturally occurring ones.

Tarring all trans fats with the same brush might convince consumers to eschew products containing natural trans fats, said Lock.

"Seeking to limit trans fats does not take into account that there are real differences between industrial and natural sources of trans fats, which are found in meat and dairy products such as milk and cheese.

"There is a growing body of scientific evidence that some of the fatty acids uniquely present in milk fat may help disease prevention.

"Whole milk contains a number of positive components, including levels of natural trans fats known as CLAs, which reduce the risk of breast cancer.

"If the EU continues to push forward with sweeping generalisation it will end up discouraging people from products that have potential benefits in terms of disease prevention."

Lock called for the public to be educated about the differences between types of trans fat, and for any legislation over labelling on food products to clearly identify what was man-made and what was naturally occurring fatty acids.

The Food Standards Agency has recommended that people cut their intake of foods containing trans fats - and has urged food companies take steps to remove them from their products.