Eigetsu from Saiunkoku Monogatari turns into Yougetsu when he drinks sake. At first it seems he's just a Crouching Moron, Hidden Badass with a side-order of Drunken Master, but it eventually becomes clear that Yougetsu, in addition to badass Kung-Fu skills, has inhuman strength, reflexes, stamina, and rapid regeneration. At one point, Eigetsu reverts into Yougetsu after having spent weeks being starved and tortured to the point where he can't stand unsupported, and in addition to being strong enough to sprint on the spot, when he's seen a brief while later, all his wounds are healed... It's eventually revealed that Yougetsu is one of eight immortal sages, specifically the Sage of White; he possessed Eigetsu to save his life. Sake brings him out because he really likes sake.
Kataoka Yuuki of Saki fame might apply, as eating enough tacos appears to be a prerequisite for her to maintain her mahjong-limited probability manipulation powers.
Devil Fruits in general, eating one gives you a super power but takes your ability to swim. Also, eating more than one will cause you to explode.
Luffy can recover from just about any injury so long as he's eaten enough meat. At one point this is even Lampshaded by Nami collecting as much meat and booze as she can to help Luffy and Zoro recover from injuries faster.
Brook is a living skeleton, so he drinks milk to heal himself, because everybody knows milk is good for bones. It doesn't actually work.
Franky's cyborg abilities are literally powered by cola.
Apparently Sanji has learned how to make "Attack Cuisine" over the timeskip, though we haven't seen exactly what it does yet.
Rock Lee from Naruto turns into a (drunken) berserker from just one sip of alcohol.
Quent Yaden from Wolf's Rain gains ability to see through the wolves' illusions after consuming some alcohol, making him pretty much the only regular human who can.
It's implied that this is a result of either him being in a constant drunken stupor (and thus immune to telepathic control), or because he has blurry vision (other characters are shown to catch glimpses of the wolves in their true forms via electronics or the lenses in the helmets worn by the soldiers hunting the wolves, or when "punch drunk").
An elderly couple is also able to easily tell that the wolves are wolves, suggesting that perhaps visual impairment may, indeed play a roll in seeing through their disguise.
This seems to be a common trait with Saiyans, their game improves on a full stomach.
Inverted during the World Martial Arts Tournament just before Majin Buu comes in to the story Vegeta reckons he could defeat Goku by punching him in the stomach when he is full and possibly make Goku throw up.
The Senzu beans also count. They can bring you from near death to full health in seconds and leave you with a full stomach that lasts 10 days (unless you're a Saiyan.)
Dragon Slayers in Fairy Tail are powerful fighters on their own, but they gain a massive temporary boost when they eat something of their respective elements, some of which can be very common things. Although, if you see fire in a grocery store it's probably not for sale.
Kinnikuman gets his strength from garlic early in the series. He mostly uses this to grow big and fight giant monsters. This possibly because the Japanese word for garlic is ninniku.
Ranma ½ has the legendary Super Strength Soba noodles, which confer herculean strength to whoever eats them. After Akane mistakenly ate Happosai's, she was able to lift, toss, juggle, and split in half multi-ton, two-stories-tall iron bells. Unfortunately, they had the side-effect of sprouting whiskers on her face until she took the antidote.
A virtual staple of Toriko. If Toriko eats a food that his Gourmet Cells crave, it'll lead to an immense power-up for him.
In Kare wa Diablo!, Meiko activates her Super Strength when she eats an anpan.
Bleach gives us Kirio Hikifune, a Supreme Chef who charges the meals she makes with her own reiatsu to power-up the people who consume them. It's also kind of a subversion: she can do this with any meal she cooks.
Tom Strong gets his longevity and physical prowess by ingesting goloka, a root native to the island of Attabar Teru. Other natives of the island also use goloka for similar benefits.
Tom Strange, the Terra Obscura version of Tom Strong, gets his powers from a concoction of his own devising called Alosun.
Pre-crisis Superman Comics guest star Captain Strong, who is a humanized Popeye, eats alien seaweed Sauncha to get super-strong.
1940's publisher Standard Comics hero Super Mouse (the big cheese) gained strength by eating "super cheese", which was made of milk from, what else?...a super cow!
In Tintin, Captain Haddock could be re-energized by alcohol. Tintin even carries around a spare bottle for emergencies.
The Swedish comic Bamse features a bear who gets super strength when he eats dunderhonung, a special kind of honey mixture made by his grandmother. Anyone else eating it gets three days of horrible stomach cramps, though his older daughter gets super-ursine strength and a tummyache — and his younger daughter, to everyone's surprise, gets neither.
Ralph Dibny, the Elongated Man, used a tropical fruit called "gingo" (and a commercially available soda made from it called "Gingold") to acquire his superhuman stretchiness. He's since died, but what're you gonna do.
Ralph's Crowning Moment of Awesome occurs in the Crisis Crossover series 52. He spends most of the series playing the role of the washed-up, super-powerless has-been, despondent over the loss of his wife, constantly swigging from a hip flask as he plays detective, searching for the person who pulled him into a phony resurrection scam. When he finally confronts the person responsible, it turns out that the flask was, in fact, full of Gingold.
Bananaman from The Dandy is a parody of superheroes who is usually a weedy schoolboy called Eric Wimp, until he eats a banana and transforms, a la Billy Batson to Captain Marvel, into Bananaman. Eating a second banana while in this form makes him even stronger.
Souperboy from The Topper involved a boy who gained superpowers after eating soup.
Some Disney comics have Goofy gaining Flying Brick powers (and a costume consisting of a red union suit and blue cape) when eating peanuts.
That Man From Rio - Adrian has pursued his girlfriend's kidnappers to a bar in a floating village deep in the Amazon. He sees them departing as he's stuck in a full-scale bar brawl. After repeated failed attempts to get to the door, he grabs a big glass of liquor and downs it, perks up, and fights his way through the melee like a booze-driven Popeye.
The Drunken Master becomes unstoppable once he has just the right amount of alcohol in his system.
Though she didn't see them as being beneficial, the shrinking potion and growth-inducing cake from Alice in Wonderland would qualify.
In modern revisions of the story, such as the Tim Burton movie or the giantess comic "Evil Alice in Wonderland", Alice grows Genre Savvy enough to use this to her advantage.
Similarly, the mushroom that makes Alice grow or shrink, depending on which side is eaten.
Though he was hypnotized into thinking he was Captain Underpants, Mr. Krupp only got his Flying Brick powers after drinking "Extra Strength Super Power Juice"... that was stored in an alien milk carton.
Live Action TV
One episode of Gilligan's Island had the castaways gaining superpowers after eating a shipment of radioactive vegetables.
The "sports candy" in LazyTown, particularly if eaten by Sportacus, but sometimes with other characters as well.
Dark Cloud had these in the forms of "favorite foods" for each character that would raise their defense. Also Gourds that increased the thirst meter and Fruits of Eden that increased the health meter. (Given the origin of the term "Fruit of Eden" and associated backstory, one would expect there to be some kind of negative consequence at some point, but there never is.)
The Fruits of Eden are carried over into Dark Cloud 2, along with the "favorite foods." Max's is Potato Pie, which make sense, as one of his most cherished memories is the potato pies that his mother used to make. Monica's is the Witch Parfait. It's never explained.
Pac-Man's power pellets allow him to temporarily eat ghosts. Super Pac-Man adds Super Power Pellets, which temporarily makes Pac-Man larger, faster, invulnerable, and able to smash locked doors.
The mushrooms in the various Super Mario Bros. games. The most common one makes him larger and resistant to damage, but other mushrooms (except for the Poison Mushroom which is an inversion) will turn him into a landscape-smashing giant, make him super-small, give him bee powers, turn him into a ghost, or give an extra life.
Though it's never specified what Mario does with them, the various flowers (fire, ice) may also qualify.
Rare Candies are another example. When a Pokémon eats one, it levels up.
And there are things (called "Vitamins") like Carbos, Proteins, and Calcium which raise certain stats, as well as drinks like Fresh Water, Soda Pop, Berry Juice, Moo Moo Milk, and Lemonade, all of which restore health.
Pokemon Black And White (as well as Black 2 and White 2) has Casteliacones, which act like Full Heals when fed to a Pokémon, removing status effects like poison or paralysis.
Lava Cookies (from Ruby and Sapphire) and Old Gateau (from Diamond and Pearl) work the same.
The Kirby video games grant temporary invincibility after the player gets a lollipop.
The original Kirby's Dreamland game also had "Spicy Food," which lets him spit fireballs.
Many, many years later, it came back as Superspicy Curry in Super Smash Bros. Brawl with the same effect.
The first game also featured the Mint Leaf (or Sweet Potato in the Japanese version) that let Kirby continuously spit air pellets for its duration. It was referenced in the anime, but there it was more of a Poison Mushroom: it made Kirby hiccup, interrupting him from inhaling to copy abilities.
In the Exidy arcade game Mouse Trap, the player can eat bones that turn his mouse into a dog, in order to catch the cats chasing him.
World of Warcraft has many food items that grant a temporary buff when consumed. Most give a 15, 30 or 60-minute buff that increases stamina and another stat depending on the food, but a few have other effects, like allowing you to burp fire or shoot lightning at nearby enemies or harmless critters), detect other players on the minimap (useful for PvP) or change in size (a solely cosmetic effect).
Power-Up Food is essential for near-endgame and endgame gameplay; there's a reason why most guilds have a dedicated Chef.
The Mists of Pandaria expansion introduced the Pandaran playable race who, as a racial trait are epicurean gourmands who get double the normal stat-bonuses provided by power-up food, they also have a skill point bonus to cooking.
In Soulbringer, herbs and mushrooms usually grant various beneficial (or sometimes debilitating) effects.
Ramen noodles in EarthBound bring characters back from the dead.
Also, eating a Skip Sandwich makes not only the eater, but all characters in the party walk faster for a while.
At the start of the game, you are asked to name your favorite food, which some NPCs will make for you (and fully restore you)
In Rune Factory: A Fantasy Harvest Moon, some foods provide stat changes, such as eating cheesecake to boost your intelligence.
The Scout in Team Fortress 2 has the Bonk! Atomic Punch energy drink that lets him dodge bullets or the Crit-a-Cola that lets him dish out mini-crits (but also take more damage). The Heavy has a Dalokohs Bar, a piece of chocolate that temporarily boosts his max HP, and the Sandvich, which restores the Heavy's HP up to max.
A more recent update introduced the Buffalo Steak Sandvich, another Power Up Food for the Heavy which, when eaten, gives him a speed boost and (like Crit-a-Cola) turns all damage he gives and receives into mini-crits. However, the user is restricted to using melee weapons for the duration of the powerup.
Wario and Garlic. In the Wario Ware games it causes him to become a Super Hero, and in the Wario Land ones, it causes health restoration... except in the first game, where it apparently causes him to become stronger and gain a viking hat for some reason.
In some of the Wario Land games, eating too much turns Wario into "Fat Wario," who can defeat any enemy by touching it and break through hard blocks.
In Breath of Fire II, biscuits (a fairly easy item to make) will permanently boost one character's stats by +1 per biscuit. If one doesn't mind grinding to get the proper ingredients, you can max out your party's stats, regardless of level, by the game's halfway point.
The Game Boy Color game "Looney Tunes: Carrot Crazy" let Bugs and Lola Bunny eat different types of carrots to get assorted powers, including flight and invincibility.
Final Fantasy XI's food is powerful enough that it can equal the effect of several expensive pieces of equipment. For instance, many melee characters use equipment that boosts strength and attack, but leave most of the accuracy buffs to sushi.
EverQuest offers this through the baking and brewing tradeskills - smoked Wood Elf, anyone? The stat boosts are usually very minor, however, and the best food tends to be an utter pain in the ass to produce, due to the rarity of the ingredients and the zillion subcombines required to make the final product. Want to make a baker cry? Ask them about the Misty Thicket Picnic (24 unique ingredients; and the recipe requires several of each to make up the 23 subcombines).
In Trog, eating a pineapple causes your dino to temporarily transform into a fully grown T-rex who can eat all those cavemen. There is also hot tamale powerup which allows your dinos to spit outfireballs.
In Jazz Jackrabbit 2, eating enough food gives you a sugar high; you cannot be defeated for thirty seconds, and every villain dies the instant you touch them.
Valvatorez:SARDINE! You want to know the secret to my power? It's the sardines. Eat them, and you will grow stronger as well.
Food cooked out of combat in Muramasa: The Demon Blade tends to have some sort of beneficial effect, but it varies from dish to dish - food effects include strength and vitality increases as well as bonuses to EXP and money drops. They all restore health and bestow Spirit, a resource needed to forge blades, though. Well, either that or you get to save it for later.
In Persona 2, you can visit restaurants for temporary stat buffs. There's no telling what a menu item will boost until you try it, with no real correspondence between cost and effectiveness - a super-cheap item might provide a huge bonus. The buff wears off after running around a dungeon for a while, then you can eat again. Characters have specific requests when they get hungry, such as fast food for Lisa or coffee for Yukino, and there's usually something of that type which gives a large boost to that character's favored stat (such as a burger that gives +8 Agility to anyone who eats it, which is Lisa's favored stat). Luck is the only stat that no food raises.
The various Teenage Mutant Ninja Turtles beat-em-ups have pizza, generally acting as a health boost but also occasionally enabling the use of special powers.
Fruits seem to work this way in the Axe Cop universe, although it isn't consistent: when Dinosaur Soldier eats an avocado, he becomes "Avocado Soldier" and transforms into a giant avocado that can shoot explosive avocados; Axe Cop eats a lemon and turns into "Axe Cop With Lemon" - basically himself with a lemon wedge on his axe and the power to throw lemon grenades; and when Telescope Gun Cop and Uni-Baby eat apples, their hands turn into apples that can shoot apples. Yeah.
Narrator: This episode was brought to you by... Karate Duo: "LUCKY CANDY!!!!!" Karate Duo #1: We are Karate Duo Numba 1! Karate Duo #2: Numba 1! Karate Duo #1: And when we need awesome powah, we eat Lucky Candy! Karate Duo #2: Lucky Candy! (Karate Duo #1 flies around.) Karate Duo #1: Lucky Candy make you fly like bird! (Karate Duo #2 also flies around.) Karate Duo #2: No, like glorious eagle! (Karate Duo #1 turns into Ryu.) Karate Duo #1: It make you strong! Karate Duo #2: How strong? Karate Duo #1: So strong! (Ryu!Karate Duo #1 does an uppercut.) Karate Duo #2: OOOOOH?! (Cut to Iggy.) Iggy: Lucky Candy make you have supah powah! (In the background, Karate Duo #1 is practicing with a katana.) Iggy: Lucky Candy make you have Hattori Hanzo's steel. Mama Duck: It hurt my mouth! Iggy: Your mouth is weak! (Iggy spits fire at the Mama Duck and does a dance of victory. There is a brief cutaway gag where Peach is running away from the Karate Duo. Cut back to Karate Duo #1) Karate Duo #1: So when you're in need of a pickup! Eat Lucky Candy! Karate Duo #2: Lucky Candy or DIE!!! Karate Duo #1: KEEYAAAH! Karate Duo #2: EEEYAAAH! Karate Duo #1: AAAAAAAH! Karate Duo #2: EEEYAAAH! Karate Duo #1: LUCKY CANDY TASTE THE GLORY!
The spinach from Popeye is probably the first andmost well-known example. Most of the time, Popeye himself is the beneficiary, but several cartoons have shown other characters eating spinach and powering up as well, such as two hilarious episodes where Popeye and Bluto are trying to get injured so that Nurse Olive can take care of them, culminating in Popeye force feeding Bluto Spinach.
Parodied in an episode of The Simpsons with Homer and a can of beer.
Parodied again at the end of the episode where Bart is put on Focusyn. He even sings a parody of the Popeye theme when he's put back on Ritalin;
When I start fiddlin'
I take ma Ritalin,
I'm poppin' and sailin' man!
Parodied in South Park with Towelie and weed. It doesn't work for him.
In the 1980 live-action movie, Popeye hates spinach. Only in the climax does he learn about it as a power-up food.
In the cartoon "Greek Mirthology", Popeye's ancestor Hercules got his strength from sniffing garlic and later found that spinach made him ten times stronger.
Lampshaded in two Warner Bros. cartoons, "Porky's Garden" (a baby chick eats some and turns into a tiny yellow Popeye—"I'll lays 'im among the sweet peas!") and "The Major Lied Till Dawn" (a bombast eats a can of spinach—or so he says—to battle a herd of wild jungle animals: "If it's good enough for that sailor man, it's good enough for me!").
Goofy temporarily transforms into Super Goof by eating a Super Goober. Other characters have consumed Super Goobers and become temporarily super as well.
Super Chicken's super sauce falls under this trope, especially since he typically drinks it from a martini glass. Although since the recipe varies with each episode, it's most likely just a Magic Feather for his own powers.
As expected, the Hanna-BarberaPac-Man cartoon showed Pac-Man and Ms. Pac-Man eating power pellets to fight Mezmaron's ghosts. The power pellets are grown in a forest.
One episode also had special power pellets that gave the characters superpowers.
In the Christmas episode, power pellets help Santa recover from crashing his sleigh, and give his reindeer the ability to fly fast enough to save Christmas at literally the last minute.
The Bugs Bunny cartoon "Super-Rabbit" has Bugs (temporarily) gaining Superman-likepowers by eating experimental "super carrots". When Bugs loses his carrots, the villain (a Captain Ersatz of Lyndon Johnson, a US Representative at the time) eats them and gets super powers as well.
For another Disney example: Gummi Berry juice. For Gummis it makes them bouncy; for humans, it makes them super-strong.
Technically, it was a meatball sub... and it didn't make him stronger... he just got fatter and caused the ropes to break.
In Mighty Mouse's first appearance (when he was called Super Mouse) he gained his powers after going into a Supermarket and eating various Super-named foods. It was a one-time thing though - the Power Up was permanant.
The Adventures Of Teddy Ruxpin has VitaminZ, which makes most species slightly stronger, but is addictive. If an illiper eats it, however, they become an armored giant with super strength and go into a berserker rage until they come in contact with enough water.
Taz Mania: In "We'll Always Have Taz-Mania", Hugh gets a Popeye-style burst of strength from orange juice, allowing him to swim up a 2000 foot waterfall pushing a boat.
Comfort food. From a simple family recipe to some type of treasured treat, it's often said that food can reduce stress. However, trying to "eat yourself happy" can also cause obesity.
Eating healthy can contribute as much or more to one's ability to perform a task as exercise and practice.
Coffee helps you stay awake, stay warm and naturally raises your heart rate. However, it can also make you jittery and increase your blood pressure.
Chicken soup if you've got a case of the sniffles.
Spicy food has been said to boost one's metabolism. If you're sick, it might unclog your nose.
It's generally recommended that you eat a snack before hitting the gym to give you the energy you need to put in a full workout.
Large quantities of protein can help with post-workout recovery and can improve your memory.