For years in mainstream pop culture, no one really thought much about Iron Man besides a few die-hard comic fans. However, even inside the Marvel comic book universe, Iron Man wasn't really much of an A-list superhero.

When Iron Man hit theatres in 2008, though, everything changed.

It was both Robert Downey Jr.'s comeback role, and the one he seemed destined to play. Much as Christopher Reeve was inseparable from the role of Superman, Robert Downey Jr. will for most fans always be synonymous with Tony Stark.

Iron Man was an unexpected monster hit, grossing over $585 million worldwide, which was enough money to kick off a whole Marvel Cinematic Universe — 19 movies and counting.

With the totally out-of-left-field success of the Iron Man movie, interest in the comic book character surged.

He's not your typical Marvel hero. Instead of the down-on-their-luck relatable characters that helped separate Marvel from DC back in the 1960s, Tony Stark was a "genius, billionaire, playboy, philanthropist."

He was also an arms dealer to boot, something that went against the grain from a fanbase that was mostly against the Vietnam war.

However, this didn't seem to matter. Fans loved him anyway, and as always, Marvel found ways to give him flaws and make him likable at the same time, which is partially why Robert Downey Jr. is an inspired choice to play him.

How much do fans really know about Tony Stark and his body, though? The comics have a rich history, and chances are there some surprises there that even hardcore fans might not be aware of.

Here are the 20 Strange Things About Iron Man's Body.

He Was Modeled On Howard Hughes

plane

Like all great comic-book character creators, Stan Lee took inspiration for many of his superheroes from real-life figures in history.

The larger-than-life Tony Stark, who seemed to live a charmed existence, was directly inspired by famous aviator, billionaire, and inventor Howard Hughes.

Stan Lee said, "Howard Hughes was one of the most colorful men of our time. He was an inventor, an adventurer, a multi-billionaire, a ladies' man and finally a nutcase...without being crazy, he [Tony Stark] was Howard Hughes."

Another modern figure fans have compared Stark to include Elon Musk, the entrepreneur and thought leader behind PayPal, SpaceX, and Tesla Motors.

The only major difference is that neither Howard Hughes nor Elon Musk moonlighted as a superhero... that we know of.

His Original Injury Has Healed, But He's Sustained Repeated Injuries That Require The Arc Reactor

Tony Stark's arc reactor is integral to his origin. After being injured in a enemy attack, he needs an electromagnet in his chest to prevent shrapnel from entering his heart.

The arc reactor powers the electromagnet, but has enough surplus energy to power the Iron Man suit, a rough version of which he built to escape captivity.

In the comic book version of the character, after a while, he no longer needs the arc reactor or electromagnet to keep the shrapnel out of his vital organs. This is also reflected in the plot of Iron Man 3.

However, because of his active superhero life, he sustained many injuries both similar and also more serious than the ones from the original enemy attack.

This forced Stark to "hack" his body using the reactor to keep many of his vital functions going.

He Had A Sentient Brain Tumor

Just like DC Comics, Marvel comics have storylines that happen on alternate Earths or alternate timelines.

In one such timeline, Tony Stark developed a brain tumor. However, it wasn't just any run-of-the-mill brain tumor - this one actually developed consciousness and became sentient.

The tumor communicated with Stark as the hallucination of a young boy named Anthony.

In technical terms, Anthony acted as a parallel processor to Stark's brain, adding to his brainpower, but it was also capable of acting and thinking independently of him.

However, when Reed Richards discovered one of the Infinity Stones was hidden in Tony Stark's brain (yeah that's weird), he sent Quicksilver to retrieve it, destroying the tumor "Anthony" in the process.

Captain America Trained Him

Stark was smart enough to know that he wouldn't always have his armor to rely on, so he had to have a plan B in case he needed to fight his way out of a jam. Captain America became his physical trainer and sparring partner.

Well, he didn't actually think that far ahead — it was more a matter of necessity.

There was a period of time where Stark was unable to use his armor, so he needed a way to defend himself if things went sideways.

Though Steve Rogers and Tony Stark don't always get along, Rogers helped train Stark so he could be more self-reliant and handle himself without the technological assistance.

When he finally got the ability to use his Iron Man suits again, those new fighting moves would still come in handy.

He Has Never Conquered His Alcoholism

Tony Stark alcohol

Battles with addiction are intense, and most alcoholics know it's a lifelong struggle to keep bad habits at bay.

Though hinted at in the Iron Man movies, producers sought largely to downplay Stark's alcoholism because they thought it was too dark.

However, you can see not-so-subtle touches here and there, including the bender in Iron Man 2 where he almost destroys his own house in a drunken brawl with his buddy Rhodey.

Iron Man was one of the first superheroes in comics to have an alcohol problem, as described in the "Demon in a Bottle" storyline in the late 1970s.

As various writers take turns with the character, Stark lapses in an out with his addiction, sometimes to disastrous results.

 He Has A Rebooted Brain

In the aftermath of the events of Civil War in the comics, Tony Stark is on the run from Norman Oswald, who knows that Stark has the only remaining copy of the registration act records of superheroes in his brain.

If Oswald gets that information, he'll have all the heroes' secrets, so Stark desperately looks for a way to delete the records without destroying his own mind.

He tries one attempt, but it leaves him in a coma. Luckily, he leaves instructions for Pepper Potts in the form of a hologram.

It's a complicated plan that requires many players, including Thor for his thunder and Dr. Strange to help usher Tony's consciousness from a trapped state inside his own mind.

Luckily the attempt succeeds, but Tony's memory is recovered only until the events before the Civil War.

He Was Once A Green Lantern (Sort Of)

Though DC and Marvel are rivals, they have launched a few joint projects together, one of them being the ambitious Amalgam line of comics, which featured fused versions of Marvel and DC heroes.

Such combinations included Batman fused with Wolverine (Dark Claw), Superman fused with Captain America (Super Soldier), and Iron Man fused with Green Lantern (Iron Lantern).

In the Iron Lantern origin, Hal Stark owns Stark Aircraft. When a simulator that he's working in takes off and flies to another planet, he crash lands near an injured alien's starship. The alien perishes while trying to communicate.

Hal uses the wreckage of the alien ship and a mysterious power source to build his "Iron Lantern" suit to keep himself alive and return to Earth.

His powers are a mixed bag of Green Lantern's energy constructs and Iron Man's technology.

Robert Downey Jr. Spent Five Days A Week Weight Training For The Role

Robert Downey Jr working out

Robert Downey Jr. adopted a punishing exercise regimen, training five days a week and taking martial arts training.

In addition to this, he never gave up his yoga practice, which helped support all other areas of his fitness. Consuming approximately 5,000 calories a day in combination with his training, Robert Downey Jr. put on an astonishing 25 lbs of muscle, effectively transforming himself to play the role.

Unlike other superhero characters like Wolverine or Superman, most of the action takes place while Tony Stark is wearing the Iron Man suit that conceals his body, so you can't even see him flexing.

However, that's not the point — the character is the man, not the suit, and audiences definitely prefer someone they see as physically "worthy" enough to wear it and believably combat intimidating threats.

 Robert Downey Jr. Had To Wear A Prosthetic Chest

Iron Man prosthetic chest

There's that great scene in Iron Man where Pepper Potts is cajoled by Stark to help him with something in his lab.

Before she knows it, she's an unwilling participant in something similar to open heart surgery, with Tony's survival at risk while she replaces the arc reactor in his chest.

Angry that he so nonchalantly talked her into something so dangerous, she's also relieved that he's alive. It's really a love scene.

Though many thought that this was just clever CGI, the special effect technicians went old school and used a prosthetic chest.

Special effects wizards used similar practical effects technology in Star Trek: First Contact.

It works convincingly well, with the additional "ick" factor of watching someone fumble around with gooey insides.

The Nano-tech Suit Is Controlled Completely By His Mind

A far cry from the crude mechanical Iron Man suit that Tony Stark first fashioned while in captivity in Afghanistan, his new nano-tech suit as seen in Avengers: Infinity War is a futuristic technological marvel that borders on magic.

Using a housing in his chest that used to be exclusively for the arc reactor and an electromagnet, it now houses an arc reactor and billions of nanites — tiny nano-tech particles that respond to Tony Stark's mind and his A.I. to form whatever mechanical construct he wants. T

he suit itself can materialize and dematerialize at will.

As seen in the movie, this means that he can create improvised weapons and tools and boost his capabilities as far as his imagination will take him, whether that means extra engine power, a hand-trap, or a sonic blaster.

In The Original Comics, His Injuries Occurred In Vietnam

In the movies, Tony Stark was attacked and kidnapped in Afghanistan while traveling with the military in a heavily armed caravan. It was there in the desert that he suffered his shrapnel wounds and later fought his way out of a cave in the very first improvised Iron Man suit.

However, in the original version from the comics back in the 1960s, the incident was set in Vietnam.

Stark was kidnapped and held captive by Wong-Chu and later escaped in a sequence very similar to the movie.

Stan Lee saw Iron Man's character as a great way to explore anti-Communist storylines related to the Cold War, as well as the development and build-up of weapons technology by the U.S. military.

As the world has changed, so have the themes.

The Nano-tech Particle Are Stored Within His Bones

Tony Stark spreading his arms in Iron Man.

The original comics have a different version of Stark's nano-suit. In this version, the nano-tech particles are actually stored within Stark's very bones and can come forth to form the suit upon mental command.

This means that Tony is carrying the suit with him at all times, and is almost always prepared for anything.

As far as we know, this technology doesn't actually exist... yet.

However, comic book and sci-fi writers have a pretty good record for writing predictively about the technology that is about to come. Star Trek predicted everything from cell-phones to iPads over 30 years ago.

The military is exploring exoskeleton suits for use with soldiers.

For now, instant nano-tech suits may be fictional, but that doesn't mean they can't eventually happen.

He Had A Falling Out With The Government Because He Was Mind Controlled By The Scarlet Witch

It must be difficult to be friends with Tony Stark, as his allegiances can sometimes feel or seem extreme.

In the events of Avengers: Disassembled, Stark was at a diplomatic meeting with representatives of many nations when he uncharacteristically went off on a drunken rant against the Latverian ambassador.

At the time, Tony Stark was actually serving as the leader of defense, but his antics against the ambassador were not sanctioned or approved by the U.S.

As a result, he had to step down from the position. However, it turns out that it really wasn't his fault — he was being mind-controlled by the evil Scarlet Witch.

Unlike the movies, the comic-book version of the character is not really one of the good guys.

Young Tony Stark Was a Genius

Both in the comics and the movies, Tony Stark demonstrated his genius at an early age. Born into the empire of Stark Industries, Stark was privileged, but he didn't coast by on nepotism.

By age 15, he had already entered M.I.T. and later earned masters degrees in chemical engineering, electrical engineering, and physics. (Though, depending on which continuity you are reading, this combination of degrees may vary slightly.)

So by the time is he an adult and finally kidnapped by enemies, he had already built and sold some of the most advanced weapons known to mankind.

He already had the know-how to build an Iron-Man suit, he just didn't have the justification or the motivation.

When he saw that Stark weapons were being sold to enemies by his own company, Tony stepped into the role of "hero" to stop it.

Robert Downey Jr. Is One Of The Oldest Actors To Play A Superhero

It really seems that Robert Downey Jr. has left the past behind him: all that yoga, working out, and clean living keeps him in excellent shape.

At 53, he's one of the oldest men to successfully play a superhero, and he didn't start until 10 years ago.

As far as older men in demanding physical roles go, he's not exactly alone. Tom Cruise is 56 and still performing all his dangerous stunts himself, as seen in the recently released hit Mission Impossible: Fallout.

Bruce Willis, Denzel Washington, and Liam Neeson are also older action stars who still deliver.

However, none of these guys are playing actual superheroes like Downey, Jr.

We're not sure how much longer he'll be doing this, but he's still knocking it out of the park.

The Suit Was Temporarily Changed To More Prominently Feature Tony's Nose

Iron Man Nose

For a while in the comics, Stan Lee thought it would be better for Iron Man's mask to be more form fitting to Tony Stark's face. The obvious way to do this would be to house his nose more prominently, so it became a facet of the face-plate.

This change didn't last long, however.

After running with it for short time, Lee decided he didn't like the feel of it and returned his face-plate to its original look.

This was probably not much of a big deal to fans — Iron Man changes his armor more often than most of us change our socks.

Still, as you can see in an animated version of the more prominent nose, we think Stan Lee's decision to go for the smooth-faced look was probably a good move.

The nose isn't wrong, it's just weird.

Iron Man's Original Armor Was Grey, Then Gold

Iron Man Gold

In the comics, Iron Man spent a long time fighting crime and evil in his original clunky grey suit.

This was going fine until he realized that ordinary law-abiding citizens were getting frightened by his appearance. This is understandable if you've never seen a rampaging giant grey robot-thing.

His girlfriend suggested that he change the color of his armor to make him seem more friendly.

Golden armor for "golden deeds," as she suggested. Tony Stark went with the suggestion and still uses gold as one of the primary hues for much of his armor.

In the movie, the suit was all-gold briefly as a result of a gold-titanium construction, but Stark thought it was "too ostentatious" so he asked Jarvis to "throw a little hot-rod red in there" to which JARVIS quipped, "yes, that should help you keep a low profile."

Shane Black Thought Tony Stark Should Be Based On Jay Robert Oppenheimer

A black and white image of J. Robert Oppenheimer

Different directors and writers have different interpretations of the Iron Man character, and the quirky Shane Black, the director of Iron Man 3, is no exception.

Shane Black thought that instead of Howard Hughes, Tony Stark should be modeled on Jay Robert Oppenheimer, one of the main scientists who helped the U.S. develop the first atomic bomb.

Like Stark, Oppenheimer was a genius at a young age and worked to help the government get advanced weapons.

After the first nuclear detonations and the kick-off of the Cold War, Oppenheimer regretted his part in developing nuclear weapons, which makes him similar to Stark as well since Stark regretted his role in unwittingly designing weapons that ended up in enemies hands.

Sam Rockwell Was Almost Iron Man

Sam Rockwell Iron Man

There were quite a few actors gunning for the role in the first Iron Man movie. When the movie was in its earliest phases of development, Tom Cruise was a favorite to play Stark.

Later on Nicolas Cage, Colin Farrell, and Patrick Dempsey were all being considered.

One of Favreau's early favorites was Sam Rockwell, who like Robert Downey Jr., has an incredible gift for character and comedic timing. (However, Sam Rockwell got a great consolation prize in the role of Tony's rival, Justin Hammer, in Iron Man 2.)

Because of his party-boy reputation, his ex-convict status, and his history of addiction, Robert Downey Jr. was considered a big risk for the studio.

His screen-tests eventually won them over, and that (in combination with some excellent insurance underwriting) made Iron Man and the rest of the MCU possible.

He Once Turned Evil

Superior Iron Man

Marvel always likes to shake things up a bit, so in the comic book event known as Axis, all of the villains' and heroes' personalities became inverted — so now good guys were bad guys and bad guys were good guys.

This is a fun "what-if" scenario that writers and fans had probably speculated about for a long time.

At the end of the Axis event, all of the heroes and villains returned to normal... except for Tony.

He stayed evil and dubbed himself "The Superior Iron Man." Writers had fun with evil Iron Man for a while, similar to what other creators did with an evil Spider-Man in Superior Spider-Man.

Eventually, Marvel brought Tony Stark back into the light after a Secret Wars crossover.

He's back to being a good guy again... for now.

---

Can you think of any other interesting facts about Iron Man's body? Let us know in the comments!