Carrots!

The carrot is not a vegetable, but a herb. Carrots used to be purple in colour, until someone decided that the orange ones tasted better (a fact that anyone who has eaten Opal Fruits/Starburst knows to be 100% true). Carrots do not improve your night vision - that's propaganda spread by the British government during WWII to 'explain' why their pilots were able to fly at night. In actual fact, it was down to the invention of radar, something the govmint and the RAF wanted to keep secret.