In Britain, but not the U.S. Of course, BK denied, repeatedly, that it had sold burgers with horse meat at all, including the U.K. There's nothing dangerous about horse meat, but as the piece points out, it leads to this larger point:

Let's make clear: The horse meat does not pose a health threat to consumers. But it does raise the question of what other fillers are in our food that we don't know about - listed or unlisted.

Among the worst is flame retardant in fish and turkey. And how about butane in your chicken (yes, the same stuff that's in your lighter) or castoreum from a beaver's behind used to make fake raspberry flavoring in Jell-O?

There's estrogen in your milk and wood pulp in fake vanilla flavor in yogurts and candy.

The nonprofit U.S. Pharmacopeial Convention has found a bunch of fake ingredients, from spices like paprika and saffron with food colorings to tea with lawn grass and fern leaves. (You can read more intheir database.)

The FDA found honey adulterated with corn or cane sugar. There's watered-down milk and pomegranate juice diluted by grape juice. Not to mention all the meat products diluted by water.

No wonder some people prefer to go all natural.