Sorbitol (the fake sugar used in diet sodas and sugar-free candy) can also cause unwanted bloating, diarrhea and those smelly farts you hate so much. This is because “sorbitol is metabolized very slowly by your body and known to display laxative properties and can cause bloating from gas-producing bacteria in your intestines.” If you are addicted to diet soda or you’re a big fan of sugar-free chewing gum, you might want to nix those items from your daily diet and see how your digestive system is impacted.