Just moderately reducing consumption of 'trans fats' may cut coronary heart disease by a quarter, but many food retailers are failing to help address the problem, according to a report by Health Which?.

Hydrogenated fats are formed by bubbling hydrogen through vegetable oil and are used to extend the shelf life of the oil. The process creates trans fats, which many experts, including the UK's Food Standards Agency (FSA), now link to coronary heart disease and believe could be even worse than saturated fats.

The investigation by the Consumers' Association's Health Which? magazine found that hydrogenated fats and therefore trans fats are found in a range of food products, such as Kellogg's Nutri-Grain morning bars, Linda McCartney vegetarian sausages and flame grilled burgers, as well as a wide variety of biscuits, cakes, crackers, packet soups and pies.

The Zutphen Elderly study led by Professor Daan Kromhout, published in the Lancet in 2001, concluded that reducing consumption of trans fats by 2.4% of total calorie intake can cut deaths from coronary heart disease by a quarter, the magazine said.

Despite moves by a few manufacturers of well-known brands to reduce the levels of trans fats in their products, the Consumers' Association said key supermarket retailers are failing to take the problem seriously enough.

Health Which? contacted three leading supermarket chains to seek their views on their use of hydrogenated fats found in their own-brand products.

While stating that Safeway policy is to limit the use of hydrogenated fats where possible, Health Which? found that Safeway's own-brand custard creams, labelled 'Healthy Choice', contained hydrogenated fats. The company said that it had not found a suitable alternative. The supermarket did point out that hydrogenated oil is always listed in ingredients lists. However, it is not included in nutrition labelling and Safeway stated that its research shows consumers are more interested in other information.

Waitrose said that it is guided by government advice and may take steps to limit hydrogenated fats in its own-brand products, should government guidelines change or technology provide suitable alternatives. Waitrose includes hydrogenated oil in ingredients lists.

Sainsbury's said that products in its 'health food selection' must not contain hydrogenated fats. However, they are used in some own-brand products and are always included in ingredients lists. Sainsbury's has no plans to review its policy as it told us there is no customer demand or government requirement.

"Our research suggests that the food industry isn't taking the issue seriously enough. Labelling must be improved to provide consumers with more information about trans fats. But it is also important that the food industry makes greater efforts to reduce the levels found in foods, particularly as they have no known nutritional benefits whatsoever," Sue Freeman, acting editor of Health Which? said.