3. Olestra (or Olean)
Source: Quartz
Found in: Fat-free potato chips, corn chips, and French fries.
Why it’s dangerous: Created by Procter & Gamble as a substitute for cooking oil, Olestra robs your body of its ability to absorb vitamins. Fun side effects include cramps and leaky bowels.
Where it’s banned: The U.K. and Canada.