A Pepper is a type of spicy fruit that can either be green, red, or blue. They are the most hated food of Bandit in Super Bandit Bros. 2. Bandit. If he picks one up, he will lose his health.
In Super Mario: The Mystery of HeartGold and SoulSilver, the peppers are briefly mentioned when Cream's Chao, Cheese, was about to vomit.