It turns out that when you "taste the rainbow" by eating Skittles, you might just be tasting something else you probably didn't bargain for. Titanium dioxide is an additive that many countries are skeptical of, but that is still ever-present in the United States.

Despite the E.U.'s concerns, Skittles aren't banned in Sweden and Norway because of the titanium dioxide additive inside the candy. Instead, the countries are more concerned about allergic reactions and hyperactivity in children caused by the product's food coloring dyes, yellow 5 and yellow 6.

Elsewhere in the E.U., if you get your hands on a packet of Skittles, they will probably taste a little different because they are colored naturally using spices, veggies, and fruits. Though the E.U. hasn't banned yellow 5 and yellow 6 dyes, it requires that any food containing the colorings be packaged with a warning.