If the health department has its way, slap chips and doughnuts may soon be much healthier and less fattening than in the past.

It has started a process of "consulting with stakeholders" to develop legislation aimed at reducing trans-fatty acids in food.

"The department of health is in the process of consulting with stakeholders with the intention to develop legislation aimed at the reduction of certain trans-fats," health spokesperson Fidel Hadebe said in a statement.

It would focus on "trans-fatty acids deriving from the process of partial hydrogenation of vegetable oil, present in certain processed and prepared foods currently for sale in South Africa".

Hydrogenation is the chemical process by which liquid vegetable oil is turned into solid fat. Partially hydrogenated oils contain trans fatty acids, which are believed to raise bad cholesterol levels and lower good cholesterol levels.

Any food cooked in partially hydrogenated oils, such as French fries or doughnuts, or containing this oil, is affected.

"All manufactured and pre-packaged foodstuffs, as well as foods prepared by restaurants and fast food outlets, currently sold in South Africa, which generally contain partially hydrogenated vegetable oil (IP-TFAs) as an ingredient, or where such oil is used for deep frying purposes, will be affected by the proposed legislation," said Hadebe.

The aim of the proposed legislation is to reduce chronic diseases associated with the "presence of trans fatty acids in the diet of South Africans".

This is in line with the World Health Organisation's (WHO) Global Strategy on Diet, Physical Activity and Health, which was adopted in May 2004, at the 57th World Health Assembly.

The department was committed to implementing regulations to reduce the intake of man-made trans fatty acids.

"Man-made trans-fats, also referred to as Industrially Processed-Trans Fatty Acids (IP-TFAs)... [are] one of the major factors contributing to the global pandemic of chronic diseases of lifestyle such as coronary heart disease, diabetes, certain cancers, and obesity," said Hadebe.

"Natural occurring trans fatty acids in animal fats e.g. in dairy products and meat, may have health benefits and are therefore excluded from the proposed new legislation."

Manufacturers can use alternative technologies for the processing of vegetable oil or use "more appropriate types" of fats and oils in their products.

Similar pieces of legislation have been introduced in Denmark, Canada and New York, said Hadebe.

"The introduction of the legislation was accomplished without noticeable effects on the availability, price or quality of foods previously containing high amounts of industrially processed trans fatty acids."

The department will kick off the process with a workshop on the issue on 22 October.