Home Radio waves She-Hulk’s Superpowers: The Science Behind Gamma Radiation

She-Hulk’s Superpowers: The Science Behind Gamma Radiation


We all know that Bruce Banner became the Incredible Hulk when he was exposed to gamma rays. Now, with the release of She-Hulk: Lawyerwe get our first look at another member of the Hulk family in the MCU, and things are a little different.

Instead of being directly exposed to unfettered gamma rays, Jennifer Walters retreats after being contaminated with some of Bruce Banner’s blood. In the comics, the contamination is the result of an emergency blood transfusion. In the series, it happens differently but the result is the same, Walters gets a version of his cousin Bruce’s powers. After seeing the show and the movies, or after reading the comics, one would assume that gamma radiation is a direct ticket to becoming a super, but the actual scientific evidence doesn’t quite support that argument.


Radiation gets bad press. In popular consciousness, we associate it with nuclear disasters and toxic spills, but it’s an ordinary part of life in the universe. Simply put, radiation is just the movement of energy through space. Everything is radioactive. You, your cat, the bowl of leftovers you eat for breakfast – and that’s before you even put it in the microwave, which uses yet another form of radiation – we live in soup all the time well mixed with radiation. Most of this radiation is more or less harmless. It’s been around longer than us, and we’ve evolved to live within it.

When we think of dangerous radiation, we actually think of specific types of radiation, types that we don’t encounter very often and that we haven’t evolved to handle well. These tend to live at higher frequencies with shorter wavelengths.

You can visualize radiation as a scale. At one end you have low frequency, long wavelength radiation. This is where radio waves, infrared and visible light are found. Moving to the other end of the spectrum, you get ultraviolet rays, X-rays, and finally gamma rays. Ultraviolet is moderately dangerous over long enough time scales. Anyone who forgot to reapply sunscreen at the beach has felt the sting of too much UV exposure. Yet UV radiation cannot be compared to energies at the end of the scale.

The further you go in the electromagnetic spectrum; the more energy the particles carry. Once you hit the X-rays, they travel fast enough to strip electrons from your own atoms. For this reason, we call X radiation and gamma radiation ionizing. Controlled exposure for short periods and not very often is not very dangerous. That’s why you don’t have to worry about getting x-rays of your teeth when you go to the dentist, but the technician wears an iron apron and stands behind a wall. Prolonged exposure to your whole body, or even brief exposure to a very strong source is a fundamentally bad idea.

On Earth, gamma radiation is produced inside the nuclei of radioisotopes such as uranium, radium and thorium. It is also produced in high-energy cosmic objects elsewhere in the universe, such as supernovae, pulsars and black holes in the form of gamma-ray bursts. They are powerful enough that if one happened nearby and hit Earth, this could trigger a mass extinction event removing the ozone layer from our planet. Basically, gamma radiation is not something to bother with.


As with most forms of radiation, it’s all a matter of degree. People are regularly exposed to gamma radiation, and sometimes on purpose. Gamma radiation is commonly used in cancer treatments precisely because of its ability to destroy tissue.

When powerful ionizing radiation comes into contact with cancer cells, the energy causes DNA degradation in the nucleus, causing cells to stop growing or replicating. Ultimately, these cells die. These treatments are carefully controlled so that they only affect the target region, slowing and hopefully stopping the cancer in its tracks. That said, nearby tissues can be affected, and doctors work tirelessly to minimize these effects.

What happens to a person after an exposure depends on what part of the body was exposed, how strong the radiation is, and how long they stay in contact with it. If the dose is high enough, you will quickly lose your hair, your lymphocytes will die making you more susceptible to secondary infection, damage to the heart and wider circulatory system will occur, and you would be incapacitated fairly quickly. Damage to the heart and nervous system can cause heart failure or seizures, and a person can die within days or weeks, even with medical treatment.

It should be noted that in some versions of the Hulk story, Bruce Banner was exposed to a relatively manageable dose of gamma radiation, based on both the amount of total radiation and the position of his body. It’s possible, depending on the specific factors of each story, that it survived without too many ill effects. Of course, Jennifer Walters wasn’t exposed directly, she got her gamma exposure secondarily from Bruce’s blood…


This is where the Hulk and She-Hulk logic really breaks down. It is true that an irradiated person can sometimes cause secondary exposure to someone else. A person who has been contaminated can transmit this contamination through contact with bodily fluids, including blood. However, by the time Jennifer enters the scene, Bruce has been the Hulk for years. Any radiation that might have lingered inside his body would have long since faded.

More importantly, only certain types of radiation remain in a person’s body for long periods of time. In particular, gamma radiation is not one of them. It is energetic enough to pass through your body at the speed of light and continue. In a hospital setting, they capture this radiation from the other side of your body with specialized shields.

Bruce would not have been able to transmit the gamma radiation to anyone else even moments after his initial exposure, let alone years later. There is no danger in being exposed to the blood of someone who has been blown away by gamma radiation, at least not from the radiation itself. A blood transfusion can be a risky business, especially if it’s still early when their immune cells have been decimated. In this case, however, they are more likely to need a transfusion than to give one.

We are left with one of two conclusions. Either gamma radiation works in a totally different way in the Marvel Universe, or it’s a name given to another substance that isn’t radiation at all. We’d like to swear Jennifer and Bruce to find out how she really got her powers, because the story as presented doesn’t hold up to scrutiny. We rest our business.