If you don’t know by now that fast food—delicious, artery-clogging fast food—is a plague upon society, decimating the health of entire communities while rocketing whole nations to the top of the obesity charts, you’re just being, well, thick.

But it's getting worse: In addition to the whole litany of abuses greasy fare can inflict on the human body—increased risk of high cholesterol, high blood pressure, obesity, increased risk of heart disease and stroke—you can probably add the big C to the list.

That's because even fast food wrappers are probably really bad for you, according to research recently published in Environmental Science & Technology Letters. Of course, no sane person actually eats fast food packaging (though we’ve seen a few over-zealous diners lick the melted cheese off a wrapper or two). But around 30% of the packaging tested in the study contained fluorinated chemicals, which have been shown in previous studies to leech into food—and, in turn, into our bodies.

The compounds, also called PFASs, are used because they help repel grease or cheese from sticking to the packaging, but they have also been linked to changes in hormones, kidney and testicular cancer, and high cholesterol. Out of all the different kinds of packaging—food contact paperboard (boxes), food contact paper (wrappers), non-contact paper (bags), paper cups, beverage containers and lids—the wrappers were the worst offenders, with 46% of samples testing for fluorine. Paperboard followed up with 20% and drink containers at 16%.

Unfortunately, the researchers gave no chain or brand identifiers, so when you pick up your next grease bomb—wait. It doesn’t matter which fast food joints use cancer paper, because you should eliminate all fast food from your diet if you want to live a long and healthy life.

Okay, FINE: So maybe you want some Chick-fil-A or Wendy’s fries every now and then. Just ask the folks behind the counter to put your food in a regular paper bag, or simply get your food out of the wrapper as quickly as you can. Or, again, you can just remove fast food from your diet. Problem solved.

For a diet that will keep you satisfied and healthy, and not craving artery-clogging crap, take a look at our clean eating guide or educate yourself on the merits of adopting the Mediterranan diet. Eat those ways and you’ll stay slim, live longer, and not get cancer from a piece of fluorine-coated paper.