|“||The healing god food used in emergencies, when demigods are seriously hurt. Ambrosia will cure almost any injury, although too much can make a demigod feverish and kills mortals. At Camp Half-Blood ambrosia comes in squares in sealed bags. On Mount Olympus you can buy it on a stick.||”|
–Excerpt from The Ultimate Guide, explaining ambrosia
In Greek mythology, Ambrosia was the food eaten by the gods, usually presented in small cubes. It gave immortality to whoever ate it (although not in the Percy Jackson universe). It is closely related to Nectar. Ambrosia was fed to wounded demigods to heal their injuries.
Ambrosia is used as healing food to be used when someone gets injured in battle. Demigods can consume it, but if they have too much it can make them feverish and mortals cannot eat it at all without it, "turning their blood to fire and bones to sand". It takes the taste of the user's favorite foods.
Piper McLean eats part of an ambrosia square when she broke her foot after falling from Festus, saying that it tastes like black bean soup her dad, Tristan McLean, used to make for her when she was ill.
When Annabeth Chase injured her leg from falling, she eats some of her ambrosia. It was said to taste like the popcorn she and her dad, Frederick Chase, ate during movie night. She says the memories helps her heal and it comforts her.
Annabeth Chase fed Sadie Kane some ambrosia to recover. Sadie says that it taste like her Grandma's Scones. The ambrosia was also given as a gift because Sadie gave Annabeth some of her healing potion that was brewed by Jaz.
Ambrosia is the food of the gods and is usually reserved for their meals. However, demigods normally have some with them, as it has a healing effect on them. Demigods are the only type of mortals that are able to eat Ambrosia, as if a human ate some, they would literally burn away as the food is too powerful for them, although, as revealed by The Staff of Serapis, magicians can eat it and live. Monsters as well are unable to eat the food without perishing. However, eating too much ambrosia at one time can cause a demigod to become feverish, as if they are burning up from the inside out. In small doses, ambrosia is able to heal a demigod of small injuries, like cuts, bruises, and fatigue. More severe injuries, like a broken ankle for example, need more time and could take up to a day to fully heal. When eaten, ambrosia normally tastes like a pleasant food enjoyed by the consumer. For Percy, it was warm chocolate chip cookies, while for Piper it was the black bean soup her father used to make her. For Jason, it tasted like the brownies from one of New Rome's bakeries, but it tasted more bitter than he remembered because he was 'not quite Roman anymore'.
- Egyptian Magicians can eat Ambrosia as well.
- In Greek Mythology, ambrosia was capable of giving immortality to mortals.