Many chips, sausages and cereals contain butylated hydroxyanisole and butylated hydroxytoluene in their ingredient lists. The waxy substances act as preservatives, keeping foods from becoming rancid. While BHA and BHT have been "generally recognized as safe" by the U.S. FDA, they remain controversial. Both substances may have some disease-fighting properties, but they've also been shown to raise cancer risks in animal tests, according to the U.S. National Toxicology Program. Both BHA and BHT are banned from foods in Australia, Canada, New Zealand, Japan and throughout Europe.

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