Americans fuzzy on trans fat sources: survey

NEW YORK (Reuters Health) - Most Americans know they should limit artery-clogging trans fats in their diets, but fewer know which specific foods to avoid, a new survey suggests.

Researchers found that of 1,000 U.S. adults surveyed in 2007, 92 percent said they had heard of trans fats -- up from 84 percent the year before. Among the trans-fat-aware, nearly three-quarters knew that the fats may raise the risk of heart disease.

Yet, when asked to name three food sources of trans fats, only 21 percent could do so -- though that was better than the figure for 2006, when only 17 percent could list three trans-fat culprits.

The findings suggest that health campaigns and media stories have boosted consumers' trans fat knowledge, but there is still more to be done, according to the researchers, led by Dr. Robert H. Eckel of the University of Colorado Denver.

They report the findings in the Journal of the American Dietetic Association.

Trans fats have become notorious because they not only raise "bad" LDL cholesterol -- like the saturated fats in meat and butter do -- but also lower levels of heart-healthy HDL cholesterol.

Trans fats are formed during food processing when hydrogen is added to vegetable oil to make it solidify; foods that list so-called partially hydrogenated vegetable oil on the label contain trans fat. Traditionally, that has included most commercially prepared baked and fried foods -- including cookies, crackers, chips, breads and french fries -- but manufacturers and restaurants have been increasingly removing trans fats from their products.

Still, consumers need to be aware of which foods may contain the fats -- and be savvy label readers in general, according to Eckel and his colleagues.

It's important, they say, for people to read the "Nutrition Facts" panel on all products, even those labeled "trans-fat-free." Such products may still contain significant amounts of saturated fat, the researchers point out.

In particular, they note, some manufacturers are using tropical oils -- coconut oil, palm oil and palm kernel oil -- to replace trans fats, and those oils are high in saturated fat.

In the survey, only 43 percent of adults had heard of tropical oils, and few said that they look for the oils on product labels.

SOURCE: Journal of the American Dietetic Association, February 2009.