Whenever people think of Fear Factor, their mind goes straight to one thing. It's not the death-defying stunts the contestants attempted and it's not series hosts Joe Rogan and Chris "Ludacris" Bridges. It's the gross situations that the people were put through.

Almost every episode saw the contestants put through at least one nasty challenge. They'd have to consume horrifying things like live bugs, aged drinks, or body parts of animals you'd never even think were edible. With it being such a staple of the show, it is difficult to narrow down a list to just ten. However, we've found the ten moments we feel are the most disgusting in the history of Fear Factor.

Be warned! These truly are disturbing moments. If you're the squeamish type, it's best you don't continue on.

Bobbing In Cow Blood

Surprisingly, this list doesn't begin with the contestants having to eat something gross. Instead, they had to dunk themselves into a giant tub of cow blood to retrieve rings from the bottom. There were 13 rings in all, so they had to submerge into the blood over and over.

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As gross as this challenge was, it also looked like something straight out of a horror film. One memorable contestant named Josh was only able to grab two rings, yet still emerged drenched in gallons of it. The same goes for the sight of those who completed the task dripping in blood.

Squirting Worms

Worms are just gross creatures. They're slimy, wiggle around in awkward ways, and live in filth. Having even to touch one sounds nasty enough for most people to rethink their place on the show. During one episode, everything got taken to the next level.

Contestants had to eat tomato hornworms. That sounds bad enough. What really made this a standout moment of grossness was the fact that these worms squirted out a substance with each bite. One shot so far it landed on other members of the cast.

Milking The Goat

Some of the toughest challenges in Fear Factor history came in parts. That was the case in a season three episode where couples competed against each other. To start, contestants had to suck milk from a goat's udder and spit it into a glass until it was filled to the top.

Once the glass was full, the contestant then had to drink that milk. The combination of sucking from a goat's udder and swallowing that milk which has been mixed with your own spit is disgusting. We're sure plenty of viewers at home lost their lunch when watching this episode.

Cow Intestines

Another cow related challenge in Fear Factor and another stomach-churning one. This combined the nasty eating aspect of the show with the terrifying side. These poor folks were reclined in the tight confines of a glass coffin that was filled with nothing but cow intestines.

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That was just the beginning. The contestants had to puncture the intestines by biting into them, suck out the horrible liquid that shot out, spit it into a cup, and then drink it. Somehow, the winner managed to do all of this in under three minutes, though she did puke almost immediately afterward.

Horse Rectum

You know this list is filled with gross stuff because horse rectum isn't even in the top five. Season three was filled with some of the grossest challenges in Fear Factor history, with this one standing out. In it, contestants were tasked with eating the rectum of a horse.

To make matters worse, the challenge was to eat a whopping 13 inches of rectum. Eating 13 inches of anything is a daunting task, but that's especially true when it's something so gross. The winner ate it all and won $50,000, but the loser gave up after eating 12 inches. Had they just stuck it out for one more inch, they would have won.

Testicles And Eggnog

Another season three entry and another case of a challenge featuring multiple items for consumption. In this holiday-themed episode, the brave souls had to eat reindeer testicles. On its own, that would be enough to make this list but the challenge was only getting started.

The contestants had only one beverage option to wash down these testicles. Usually, eggnog is a refreshing holiday drink. Since this is Fear Factor, it was eggnog that was over a century old. An expired drink and the genitals of an animal doesn't sound like the kind of Christmas dinner we want.

Sheep Eyes

While season three had a lot of gross moments, season one is arguably tops in that category. Just seven episodes in and this ridiculous challenge happened. For a chance at $50,000, these people were asked to eat the eyes of sheep. Makes you wonder if that money is worth it.

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Just thinking about the texture of eyes and the fact that they're, you know, EYES, is disgusting on its own. But the whole thing got even more awkward because live sheep surrounded everyone as they ate. These guys were getting watched by the very eyes they were eating!

Leech In Throat

Team challenges can get tough. In this season seven installment, one team member had to sit in a bathtub full of leeches. Some were in tears as these creatures crawled all over their skin. Their partners had it worse because their goal was to suck the leeches off of them.

Once they sucked the leeches out, they had to eat them. The gross moment that causes this to rank so highly is that one of the leeches latched on to someone's throat. It caused him to cough up the leech, along with a fair amount of blood.

Blended Rat

In season five, Fear Factor provided viewers with one of the most disgusting things ever put on television. The premise was simple enough. A dead rat was blended up into smoothie style drink for these brave challengers. They had to consume an entire bowlful of it.

For a taste of how gross this is, know that there was someone who sued the show over it. A viewer filed a lawsuit for $2.5 million, claiming the episode made him and another person physically ill. The suit was ultimately dropped, but it gives you a feel for just how bad this was.

The Time They Went Too Far

Our top pick goes to the one time that Fear Factor went too far. This is a show that toed the line often, but they crossed it with this one. During season six, an episode saw contestants tasked with drinking copious amounts of both urine and semen from donkeys.

NBC aired Fear Factor and their parent company, Comcast, demanded the episode not make it to TV. Instead, a rerun was aired in its place. The clip can still be found online. Be warned that if you watch it, there's a good chance you will find yourself gagging almost as much as the people drinking the stuff.

NEXT: 'MeatEater' with Joe Rogan & Bryan Callen Airs April 28th