Mounting evidence suggests that TFAs raise LDL (bad) cholesterol levels, causing the arteries to become more rigid and clogged. An increase in LDL cholesterol levels can lead to heart disease.
A trans fatty acid is an unsaturated fatty acid molecule that contains a trans double bond.
The industrial food process of partial hydrogenation changes the molecular configuration and properties of oils used for baking, frying, shelf-life, and other purposes, creating trans fatty acids (TFAs) in the oil.
As a result, food makers are under increasing pressure to find alternative processes and ingredients to cut the TFAs from their food products.
While trans fatty acid consumption has been associated with an increased risk of cardiovascular disease, the relationship may only be partially explained by the adverse effect these fats have on lipid profiles, say scientists.
Researchers at the Harvard Medical School in the US found strong evidence that trans fatty acids adversely affect endothelial function, which might partially explain why the positive relation between trans fat and cardiovascular risk is greater than one would predict based solely on its adverse effects on lipids.
They reached their findings after examining whether trans fatty acid intake could also affect biomarkers of inflammation and endothelial dysfunction.
In order to assess the dietary impact of trans fatty acids the team conducted a cross sectional study of 730 apparently healthy women from the Nurses' Health Study, aged between 43 and 69 years, and that had filled in food frequency questionnaires in 1986 and 1990.
Biomarkers found to be higher in the quintile of subjects with the highest consumption of trans fatty acids compared to those in the lowest quintile were: C-reactive protein (CRP) 73 per cent ; interleukin-6 (IL-6) 17 per cent; soluble tumour necrosis factor receptor 2 (sTNFR-2) 5 per cent; E-selectin 20 per cent; and soluble cell adhesion molecules (sICAM-1 and sVCAM-1) both 10 per cent.
These latest findings are published in the March 2005 issue of the Journal of Nutrition 135:562-566.
Eyeing market opportunities, a host of ingredients firms have already launched a raft of speciality oils to target 'trans-free' requests.
Last month Germany's Bayer CropScience and US firm Cargill announced a link-up of technologies on seed development to create a new oil, for launch by 2007.
"Bayer CropScience will provide its InVigor line of hybrid rapeseed high-yielding seed and Cargill, the 'desirable oil traits' for producing high oleic rapeseed oil," a spokesperson at Bayer CropScience explained to FoodNavigator.com.
Cargill and Bayer CropScience will join other oil giants in the battle for market share.
Last year US firms Dow AgroSciences, Bunge and DuPont all launched their various brands of zero or low trans fat oil. They join Archer Daniels Midland that previously developed the NovaLipid line of free and low trans fat products, produced using an enzymatic inter-esterification technology.
New legislation is also pushing demand for alternative processes and ingredients. Incoming rules in the US mean that by 1 January 2006 all trans fats in food products will have to be labelled on the nutritional panel.
Europe has yet to introduce a similar rule, but consumer organisations are pressing for such transparency and food makers are feeling market pressure to slice TFAs from their products.
In 2003 Denmark became the first country in the world to introduce restrictions on the use of industrially produced trans fatty acids. Oils and fats are now forbidden on the Danish market if they contain trans fatty acids exceeding 2 per cent.