Hunger Hyperbole

Oftentimes in life, when people are really hungry, they'd make a statement that they are so hungry that they could eat a horse. Sometimes, this may often overlap with Hold Your Hippogriffs.

Examples of Hunger Hyperbole include:

Anime and Manga

From Digimon Adventure:

Tai: I'm so hungry I could eat a horse!

Izzy: I'd settle for a small cow.

I distinctly remember Ash from "Pokémon" saying at one point, "I'm so hungry I could eat a Horsea!"

Comic Strip

One Mad strip. Four teenagers in a diner.

Teen #1: "I'm so hungry I could eat a horse!"

Teen #2: "I'm so hungry I could eat a rhino!"

Teen #3: "I'm so hungry I could eat an elephant, including trunk and tusks!"

Teen #4: "Now I lost my appetite!"

Film

Played with in Apollo 13. Astronaut Fred Haise is getting sick during the flight; Jim Lovell asks if he'd like to skip the next meal, and he responds, "Are you kidding? I could eat the ass end out of a rhinoceros."
In The Lion King, Simba says that he's so hungry that he could eat a zebra.
Pappas of Point Break gave us "I'm so hungry I could eat the ass end out of a dead rhino!"
In One Hundred and One Dalmatians, the puppy Rolly insisted "I'm so hungry I could eat a... a whole elephant!" (even though he just ate).
Flight of the Navigator gave us this conversation:

David: Where do you go next, Max?

Max: Back in time to when I picked up my creatures. By now they're so hungry, they could eat a zigzog.

David: What's a zigzog?

Max: Kind of like a hippo, but with feathers.

An unusual variant by Vic from Neighbors: "Ramona and I haven't eaten all day. We could eat a baby's butt through a park bench."
Fred from The Foot Fist Way gives another strange variant: "I'm so hungry I could eat a grown man's ass right now!"
McCabe and Mrs. Miller:

Mrs. Miller: I'm hungry enough I could eat a bloody horse.

John McCabe: Well, at Sheehan's place you probably will.

Mrs. Miller: Ah, the frontier wit, I see.

Phido the Vulture in The Princess And The Cobbler: "I'm so hungry I could eat a vegetarian."
Itchy from All Dogs Go to Heaven 2: "I'm so hungry, I could eat a shoe."
Roy from White Lightning: "I'm so hungry I could eat the tail-end out of a hobby-horse."
Nan from The Bad Mother's Handbook: "When's tea ready? I could eat a buttered frog."
From Sweet Land:

Brownie: You hungry? hungry?

Inge: I could eat a horse.

Brownie: Well we could find dat.

Cheech and Chong - The Corsican Brothers: "I'm so hungry I could eat a bowl of lard with a hair in it!"
- A squickier version from Things are Tough all Over; "I could eat the crotch out of a dead horse!"
In (at least) the Rankin/Bass Productions adaptation of The Return of the King, Frodo is so parched of thirst as they approach Mount Doom that he muses "if Sauron himself were to offer me a glass of water, I'd shake his hand."

Literature

In the Myth Adventures book where he masquerades as a king, Skeeve accidentally comments to the cook that he's hungry enough to eat a bear. Shortly thereafter he's served a whole, roasted bear.

Live Action TV

Buffy the Vampire Slayer ("Faith, Hope & Trick"):

Faith: God, I could eat a horse. Isn't it crazy how slaying just always makes you hungry and horny?

Angel ("Carpe Noctem"):

Angel: [as Marcus] Somebody say something about food? I could eat a horse.

Mash ("The Bus"):

Col. Potter: I'm so hungry I could eat a horse. May the First Cavalry forgive me.

The Addams Family ("Morticia, the Matchmaker"):

Morticia: Mama is cooking up a real surprise.

Gomez: I am so hungry I could eat a wolf.

Morticia: Gomez, you guessed it!

The Waltons ("The Homecoming: A Christmas Story"):

Mary Ellen: I'm so hungry I could eat a horse.

Grandma: If this depression gets any worse, you may have to.

Gunsmoke ("Custer"):

Chester Goode: I'm so hungry I could eat a whole hog.

Marshal Matt Dillon: This is all the hog you get this morning.

Toby from Power Rangers Mystic Force ("Rock Solid"): "I'm so hungry, I could eat the Oldies section."
Archie from A Nero Wolfe Mystery ("Prisoner's Base: Part 1"): "I'm hungry! I had a soda fountain lunch. I could eat a porcupine with quills on it. Let's go home!"

Video Games

In Zelda: Wand of Gamelon, Link says that he's so hungry he could eat an Octorok.

Web Comics

In Flaky Pastry the horse version is used. Cue Zintiel coming back to the camp with a dead unicorn.

Western Animation

Veggie Tales: In "The Gourds Must be Crazy" (from "Are You my Neighbour"), Jimmy and Jerry Gourd start trying to one-up each other on statements about their hunger. The conversation ends with Jimmy saying he could eat an entire planet. Then it turns out this isn't hyperbole at all: the Gourds save the ship by eating a popcorn ball meteorite.
- This gets a callback in a later episode, "Dave and the Giant Pickle". This time, since the Gourds are playing the parts of ancient Israelites, the conversation plays out rather differently:

Jimmy: You know, sometimes I get so hungry, I could eat a whole camel!

Jerry: Oh yeah? Sometimes I get so hungry, I could eat a whole spaceship!

Jimmy: What's a spaceship?

Jerry: …I have no idea.

In The Magic School Bus episode "For Lunch", Arnold begins to insist "Not hungry? But I could eat a..." before Wanda, inside his stomach and pretending to be his conscience, cuts him off and forces him to drink instead.
Adventures of Sonic the Hedgehog gives this mixed metaphor:

Sonic: Eat our dust, Coconuts!

Tails: I'm so hungry I could eat our dust!

Family Guy episode "Mr. Griffin Goes To Washington".

Chris: Can't we eat? I'm so hungry I could ride a horse. I don't get it. Well, I could ride it to the store, I guess.

While stranded on an island on The Simpsons.

Terri: I'm so hungry I could eat at Arby's!