Sodium nitrite, a preservative found in many processed foods, can be deadly. A diet high in sodium nitrite can lead to a health condition known as methemoglobinemia, which is the inability of red blood cells to transport oxygen throughout the body. The condition can cause many respiratory issues and even be fatal. This isn't to scare you, just to create awareness. To avoid any unwanted side effects, simply check your food labels before buying.
How to cure pancetta. I'm going to do this just as soon as I can track down some "pink salt". I bought the pork belly today, which came in an unmarked ziplock bag from the freezer case of an Asian grocery store. I'm glad I asked, or I never would have found it!