While fast food will likely never be mistaken as healthy eats, most fast food chains, including McDonald’s, Burger King, KFC, and most recently Long John Silver’s, have realized that using oils containing trans fats, which increase your bad cholesterol and lower your good cholesterol, is probably a bad idea. But not every major chain is stepping out of the fast food stone age.

According to the Center for Science in the Public Interest — who may be nice folks but who some of us would never open our cupboards to — Church’s Chicken is now the largest fast food chain that still fries uses trans fat-containing partially hydrogenated oil to cook up their food.

The chain, which has around 1,200 locations in the U.S., does use trans-fat-free oil in California and New York and other locales where trans fats have been regulated or banned, and it also claims that it is trans-fat-free in company-owned stores. So even though it has the ability to cook its product in a less-unhealthy oil, Church’s stores around the country continue to use the seriously unhealthy stuff.

The American Heart Association says your maximum daily intake of trans fat should be around 2 grams, but CSPI says the typical meal at Church’s runs anyhere from 5 grams to 15 grams of trans fat — and that’s based on the company’s own nutritional info. As the organization’s tests of Long John Silver’s food showed, the reality can sometimes be much worse.

CSPI says that Church’s promised in 2007 to transition away from trans fat by 2008, but has only done so at company-owned locations. Considering that only around 1-in-5 Church’s locations are company-owned and that the average consumer has no idea which stores are corporate and which ones are franchised, there’s no easy way for the customer to know which oil his chicken is fried in.

“Church’s reckless marketing of foods with trans fat shows contempt for, and needlessly endangers, its customers wherever trans fat is not limited by law,” CSPI executive director Michael F. Jacobson wrote in a letter to Jim Hyatt, CEO of Cajun Operating Company, Church’s corporate parent.

On the subject of fried chicken chains, it should be noted that Popeyes uses in a combination of beef tallow, partially hydrogenated beef tallow, and partially hydrogenated soybean oil. This results in a lower trans fat level than what you’d find at Church’s, but a higher saturated fat count.

We tried to reach out to Church’s to get comment on CSPI’s claims and criticism, but received no response from the chain.

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