A reason to duck the foie gras?

If you've ever felt bad for the ducks and geese that go into your foie gras, you possibly, just possibly, might want to save some of that sympathy for yourself.

Duck livers — especially the fattened ones — are rich in amyloid fibrils, proteins that are normally found as single units in healthy cells but clump together into long chains in several types of diseased cells. Now pathologists at the University of Tennessee Graduate School of Medicine say that the fibrils from foie gras, when eaten, can accelerate the formation of harmful protein in the bodies of — well, just certain mice, so far.

But, the scientists add, the same thing might hold true for people.

The research, published online today in the Proceedings of the National Academy of Sciences, studied how these amyloid proteins cause other proteins in cells to mis-fold and form brand new amyloid deposits that contribute to diseases such as arthritis, Alzheimer's, Parkinson's and mad cow disease.

The researchers wanted to see if amyloid naturally present in foie gras — when fed to mice — could induce the buildup of another type of amyloid (one associated with rheumatoid arthritis) in the spleen, liver and kidneys.

Their finding: 62% of mice who were fed fibrils from foie gras had deposits in all these organs after 8 weeks, compared with none of the controls. The scientists suggest it might be possible that if people eat lots of amyloid protein some of the fibers might enter the bloodstream, move to tissues and form amyloid, contributing to disease.

So far, mad cow and related diseases are the only ones that have been shown to be transmitted by eating food. But researchers have seen amyloid induction before when stuff is injected — such as in 2005, when a group of Swedes injected dissolved silk fibers, amyloids derived from yeast and a bacterial protein called "curli" into mice, and amyloid was later found in their organs.

But you're less likely to order a big plate of "curli" the next time you're out at a swanky restaurant, right?

— Chelsea Martinez