When you party your vacation away McDonald's and other fast food joints is a necessary and well used food pit-stop. But

think again before  you order those fries as well.

This is probably a bonus/special clip from Morgan Spurlock's documentary movie about his special McDiet where he only ate food from McDonald's for several months. The result was of course disastrous for his health.

The frying oil?
Why won't McDonald's fries break down? Is it some kind of special super-nasty frying oil they use?