Golden egg
At the beginning of the game, if you leave a hen alone in Pueblo they should lay at least one golden egg (which fully restores health when used). Go to the weapon/health screen and select the egg. It should allow you to equip the egg. At the screen, Leon will throw the egg up and down, looking smug. Additionally, the golden egg is the best healing item, as it fully heals you and only takes one space in your case.