Laboratory tests released today by the Center for Science in the Public Interest show that Long John Silver’s Big Catch meal, when comprised of fried fish, Hushpuppies, and Onion Rings, has an astonishing 33 grams of trans fat—the most powerful promoter of heart disease in the food supply. On top of that, the meal has another 19 grams of saturated fat, which also promotes heart disease, and nearly 3,700 milligrams of sodium, which promotes high blood pressure and stroke. It’s easy to find fast-food meals with more calories—the Big Catch has “only” 1,320—but when it comes to clogging arteries, CSPI says the Big Catch is by far the “Worst Restaurant Meal in America.”

What most startled CSPI researchers was the 33 grams of trans fat in the Big Catch meal, all of which comes from industrially produced partially hydrogenated frying oil. The American Heart Association recommends that people limit themselves to about two grams of trans fat per day—or about as much as one might consume from naturally occurring trans fat in milk and meat. In other words, Long John Silver’s Big Catch meal with onion rings has 16 times as much trans fat as the heart association recommends—more than two weeks’ worth.