The New York City Department of Health and Mental Hygiene has asked the city's restaurateurs and food suppliers to voluntarily make an oil change by eliminating partially hydrogenated vegetable oils from the kitchen.

Partially hydrogenated vegetable oils have been chemically modified and contain relatively high levels of trans fat, which significantly increases risk of heart disease, the city's top cause of death, the department said. Commercial vegetable oils used by restaurants for cooking, frying, and baking often contain trans fat, as do many margarines, shortening, and pre-fried foods, baked goods and snack foods.

DOHMH is announcing this new educational initiative following recently released federal dietary guidelines, which recommend that consumers keep their trans fat intake as low as possible. While many nutrition labels already indicate trans fat content, the federal Food and Drug Administration is requiring that trans fat content be listed on all nutrition labels starting 1 January 2006.

"New York City's restaurants are the best in the world but they can be even healthier" said DOHMH Dr Thomas R Frieden. "Trans fat is artificially added to the foods we eat and is easily removed. To help combat heart disease, the number one killer in New York City, we are asking restaurants to voluntarily make an oil change and remove artificial trans fat from their kitchens. We are also urging food suppliers to provide products that are trans fat free."

"Heart disease is the leading cause of death and disability in the nation," said Robert Eckel MD president of the American Heart Association. "Trans fat increases the risk of heart disease risk because it raises total cholesterol and bad cholesterol (LDL), and lowers good (HDL) cholesterol. Similar to saturated fat which we get from meat and dairy fat, eating high levels of trans fats can increase the risk of developing heart disease, and this initiative, combined with efforts to reduce saturated fat, are essential ingredients for good heart health."

"New York City is world renowned for our culinary diversity," said E Charles Hunt, executive vice president of the New York State Restaurant Association. "Working together to reduce trans fat from our kitchens will be one more way to ensure an enjoyable and healthy experience for the City's 8 million residents and the millions more who visit every year."

Preliminary results from a sample of New York City restaurants found that 30% of restaurants used oils or fats known to contain partially hydrogenated vegetable oil for cooking or frying, or in spreads, such as margarine. As part of its educational push beginning this month, the Health Department is sending out letters and an information bulletin to more than 20,000 restaurants and 14,000 supermarkets and food suppliers to alert them to the dangers of trans fat, how to identify it, and how to replace trans fat with healthier options in the kitchen.

"Because many commercial products are not required to indicate trans fat content on the label, many restaurateurs and food suppliers may not know they are using oils with trans fat," said Sonia Angell MD MPH, director of DOHMH's Cardiovascular Disease Prevention and Control programme. "Restaurant owners should look for the words 'partially hydrogenated' in the ingredients list to know what ingredients are going into their food."