The film Captain America: The First Avenger showed the transformation of both the titular character and his arch-nemesis, Johann Schmidt, aka The Red Skull. While both men took the same super-soldier serum developed by Dr. Erskine, there is a major difference in how the formula reacted to their bodies. Steve Rogers became the super soldier that we all know and love whereas Schmidt's face was left red and disfigured.

Both of them were regular humans who took the same formula, so how did they end up so different? A new fan theory on Reddit from user u/rafael-a puts forward a possible explanation for these wildly contrasting outcomes.

Red Skull's Face Was Disfigured By Bacteria

Steve Rogers MCU

The theory suggests that the reason why Steve Rogers did not end up with his face disfigured was because of penicillin. Just prior to Roger's transformation in Captain America: The First Avenger, Dr. Erskine injects him with penicillin beforehand. This was important as penicillin is a form of antibiotics that work to kill bacteria within the body -- an essential step because Erskine's super-soldier serum supposedly enhances microbes as well. Rogers also underwent his massive transformation within a sterile pod, another necessary step to avoid his body having any further contact with surrounding bacteria.

Johann Schmidt, on the other hand, did not take the serum within a sterile environment, instead opting to do so within his HYDRA laboratory. The serum also enhanced harmful bacteria within his body as he did not take a dose of penicillin nor was he seen taking any other measures to make sure his body was as clean as can be. The bacteria grew in a way that destroyed the skin on his face (and likely other parts of the body) and would have killed him if it wasn't for his enhanced healing factor, leaving his body in a constant battle against super bacteria.

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The Super-Soldier Serum Enhances Everything

Red Skull Captain America The First Avenger Featured

Later on in the film, Rogers tells Peggy Carter that he cannot get drunk due to his increased metabolism, which is said to be about four times that of the average person. If the rest of the body received the same level of enhancement, it would mean that the penicillin within him would have also been enhanced greatly, leaving him with a much stronger immune system. The environment around him could have also been affected and enhanced, hence why it was important for him to be in a sealed pod.

Assuming that the reason why Rogers was in a pod was to keep his surroundings free from harmful bacteria, the Red Skull would have unintentionally enhanced the microbes surrounding him, which in turn would go on to attack his body -- but not killing him, due to his healing abilities. This is actually very similar to why Deadpool's body was malformed after his experimentation, as his cancer cells were enhanced at the same time as his healing factor, meaning his body is constantly fighting off cancer and he can never heal himself completely as a result.

What About The Winter Soldier?

Bucky and Captain America

This theory could also explain why Bucky Barnes, aka The Winter Soldier, did not return to the films with destroyed red skin. Steve Rogers' super-powered best friend was captured and experimented on shortly after Erskine's formula was lost. It would turn out that Zola created his own version of the super-soldier serum and performed the experiment on Bucky. Unlike Red Skull, Zola likely knew the effects of his formula and was not in a rush to implement it, giving him more time to properly perform the procedure on Bucky. It was also likely that Bucky was not his first trial subject, and perhaps over a few trials, Zola would know to sterilize the body beforehand.

Unlike many theories regarding the MCU, this one seems to be quite likely as there is some sound science around it. While in the film, the comment about Rogers being injected with penicillin was played off for laughs, if this theory is indeed true, then the use of penicillin was a very important detail that actually made all the difference. If it wasn't for the clean environment, Captain America might have ended up looking VERY different from how we know him now.

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