A study out
of the Harvard School of Public Health in
"Our research follows several studies that have all come up with similar results," says Alberto Ascherio, M.D., Dr.P.H., lead investigator of the study. "The bottom line: trans-fatty acids do increase the risk of heart attack."
One of the toughest things about trans-fatties is figuring out just how much you're eating.
"The biggest offenders are definitely margarine and shortening," says Lisa Litin, R.D., research dietitian at Harvard School of Public Health, "but it's hard for consumers to know what foods to avoid because trans-fatty acids are never explicitly identified on the labels."
There are clues, however. Look closely at the ingredients section on a product you eat often. If you see the words hydrogenized or partially hydrogenized vegetable oil, you can be sure there's some trans-fatty acids in that food.
Since hydrogenation involves making an oil into a solid, the more solid the foodstuff, the more hydrogenation the food has undergone, and, generally, the higher the trans-fatty acid content.
"Soft margarines, like the ones sold in tubs, have substantially lower levels of trans-fatty acids than the harder margarines sold as sticks," says Litin. Whipped vegetable shortening, like Crisco, is also very high in trans-fatties.
In a fast-food situation, the tip-off could be "made with 100% vegetable shortening"--sounds harmless, but it usually signals the use of partially hydrogenated vegetable oils.