Bananaman

While you may remember the cartoon, Bananaman started off as a British comic book.
Titular Characters
The main character is Eric Wimp. He is a schoolboy who lives in Nuttytown. When he eats a banana, Eric transforms into the adult superhero Bananaman, who has the basic Superman powers. However, Bananaman is accident prone and moronic often defeating the villains by mistake. He can eat bananas for extra powers (although how this works varies from story to story). He has a weakness for moldy bananas. He has a Fortress of Solitude-like headquarters in the North Pole and a sidekick Crow (a talking version of his namesake).
Overview
Bananaman was a parody of Superman, Captain Marvel and various Silver Age superheroes. The comic was characterized by eccentric British humour and slapstick. The main character was given two origin stories:

• Eric was an alien from the moon that was sent to Earth. The explanation for his powers is that because bananas look like crescent moons.
• As a baby, he accidentally ate a banana that had "saturnium" hidden in it by Doctor Gloom.

Bananaman's villains tend to either parodies of pre-existing villains (such as the Scarlet Witch parody Witchy Woman, the Doctor Doom stand-in Doctor Gloom and the Catwoman homage Shunk Woman) or food-related (such as Appleman, Captain Cream, Kiwi Fruit Girl and Bubblegum Bert). Bananaman was aided by an Irish policeman Chief O'Reilly (who calls up Bananaman when something need him). However, O'Reilly never learns Eric and Bananaman are the same person.
References:
http://en.wikipedia.org/wiki/Bananaman
http://www.comicvine.com/bananaman/4005-45871/