There isn’t much that’s deadlier than nuclear war … except maybe what comes /after/.


Don’t get me wrong. If you’re close enough to the blast of an atomic bomb, there’s not much hope of getting out alive. 


But even if you’re far enough away to survive the /explosion/, you’re not out of the woods. In the aftermath of a nuke, you’re looking at an environment splattered with radioactive materials. Worse still, the land, the buildings, and even the /air/ could all wind up becoming radioactive.


Here’s the thing though: some people stand a better chance in that environment than others. And I’m not talking about whether you were far enough away or hid in a shelter.


Some people’s /bodies/ help them withstand the effects of radiation more than the rest of us. In other words, science might be able to identify the people who would be the last ones standing in a nuclear apocalypse.


[intro]


Nuclear war is deadly. But understanding /how/ involves getting in the weeds. So allow me to grab my machete and guide you through that process.


It comes down to radioactivity, which has to come from somewhere.


Starting at the beginning: If you’re engaging in nuclear warfare, you’re gonna need a thermonuclear bomb. That bomb basically works by compressing a hunk of radioactive material so that its atoms split apart. 

As the atoms bust open, they nudge the atoms next to them to also split in a chain reaction called fission. Eventually, all the energy from those unfurled atoms creates an explosion. 


That explosion compresses a different chunk of material with lighter atoms that are more inclined to fuse together to release even more energy in a process called fusion, which creates an even bigger explosion. 

The blasts from the fission and fusion explosions happen when neutrons in the heart of atoms are flung out.


So a radioactive substance is anything that has unstable atoms, spitting out energetic particles as they fall into a more stable, low energy state. 


Your initial nuclear exposure would mostly come from all the radioactive mess spewed everywhere by the bomb, in the form of alpha radiation. 


While the chain reactions in the bomb are setting off, fission can sometimes end up with two protons and two neutrons stuck together, shooting out at once. Those are called alpha particles.


Alpha particles pack a /serious/ punch on the energy front. But thankfully, because they’re relatively heavy as far as particles go, they can’t travel very far. Even if some radioactive material was on your shirt, the shirt and even your skin would stop most alpha particles from getting into your body. .


[side camera] Take the wins where you can get them, because um… we're going somewhere.


The explosion sends a whole bunch of in-tact nuclear material from the bomb everywhere, including up into the air where the wind and the atmosphere spread them around like the worst confetti ever.


Whatever bits of alpha-emitting gunk you inhale or consume can get deep into your lungs, throat, and blood stream. And if alpha particles are bombarding you from the inside, you’re in for a bad time.


When those particles smash into your cells and especially the DNA inside them, it can stop your organs from working and cause mutations that lead to cancer.


The overall danger comes from the amount of energy your body absorbs from the particles, since that’s what breaks apart your DNA.



It’s measured in units called Gray. And a nuclear blast would expose you to anywhere from a few thousandths right up to two full Grays of energy, and maybe more, but if you're that close to the blast radius, death from fireball might be a more likely outcome. To put the Grays into context, a harmless mammogram at a hospital delivers about 3 thousandths of a Gray, and 5 Grays can be lethal. 


So depending on where you were, the bomb would produce enough radioactivity to cause some serious damage but also with the potential to survive it.


But the danger isn’t just from what you breathe in. Those neutrons cover everything in the surrounding area. And when they find their home in the stuff that makes up buildings or soil, they end up turning /those/ materials radioactive too.


Then there’s that newly radioactive wasteland left behind where the bomb went off. The ground, pipes, walls, and a lot of the stuff there in general are more likely to emit highly energetic electrons which are called beta radiation. 


Thick clothes can still keep you pretty safe against beta radiation, but with enough direct contact with your skin, you’d get serious burns, along with the same risks as alpha radiation if any beta-emitting stuff winds up in your food, water, or air.


As if that wasn’t enough, lots of other freshly-turned radioactive elements in the stuff all around you would be emitting the last culprit on the radioactive bulletin board: gamma radiation. 


This is electromagnetic waves, like visible light or x-rays, but even more energetic. Like an x-ray, gamma rays can go right into you, no matter what you’re wearing, without any issues. 

The only reasonable way of dodging gamma radiation is being far away from the stuff emitting it… which might be hard in a radioactive landscape.


So gamma, along with some alpha and beta radiation, is what’s going to separate out the fallout victims from the plucky survivors. And since gamma radiation is way more dangerous, pretty much all of the research I’m covering in this video focused on gamma radiation.


And it turns out, about half of us have one form of advantage here.


Biological males are less likely to die or develop cancer from radiation than biological females.


A 2019 study by Canadian researchers, published in the journal “Frontiers in Genetics,” looked at the evidence from the victims of Hiroshima and Nagasaki nuclear bombings and those affected by the Chernobyl disaster. 


They found that women have a /50% higher/ incidence of cancer and death from radiation than their male counterparts.


Data from a Russian nuclear facility also showed that individual kinds of cancer triggered by radiation, like lung, liver, bone, and thyroid, are more common in women than men who experienced the same level of exposure.


A 2022 study in the Journal of Personalized Medicine partly chalks this up to hormones produced in the ovaries, like estradiol, ramping up the absorption of radioactive chemicals by your cells. 


On top of that, radiation seems to accumulate in reproductive organs. And the increased mass of female reproductive organs and breast tissue might also provide a bigger target for radiation to hit. 


There’s not a whole lot of data on trans folks and how hormone treatments might affect their sensitivity to radiation. But if ovaries, breast tissue, and their associated hormones are the problem, then anyone with more of that stuff might be at some of the same disadvantages.


So we’ve narrowed the survivors down by about half. Another thing that can change your odds in the wasteland survival scenario is your age.


This sucks to hear but probably isn’t too surprising. Studies looking at people close to both the Hiroshima and Nagasaki bombs found that children were at much greater risk of cancer given the same amount of radiation. In fact, the younger the child, the more vulnerable they were.


The cause seems to be that, well, kids are growing. Their cells are generally splitting off more rapidly and growing too. 


But that growth process is really vulnerable to being disrupted by radiation, and can lead to tumours.


The good news is the risks associated with growing up start tailing off as you get older. The bad news is, new risks start popping up in adulthood. 


From around your forties onwards, your body starts to more frequently develop what are called pre-malignant cells, the kind with abnormal changes to their DNA. 


Ordinarily, our bodies can deal with these wonky cells by repairing their DNA, triggering them to self-destruct, stopping them from dividing, or even getting the immune system to attack them. But radiation can make the effects of that DNA damage even more intense and disrupt the body’s usual repair mechanisms. 


Which is why, from about 40 years and up, your radiation risk starts going up again. There’s less capacity to keep the pre-malignant cells from turning into actual cancer. 


That means there’s a sweet spot between about twenty to forty years old where your body is least sensitive to radiation. Those are the people most likely to survive the nuclear apocalypse. But there are still more factors to consider.

It’s not just age that causes DNA repair mechanisms to make your body more sensitive to radiation. From the moment we’re born, our genes-- beyond the ones that determine our sex-- can give us life-long sensitivity to radiation.


Conditions like ataxia telangiectasia or just A-T, are genetic syndromes that affect the genes responsible for DNA repair. And if your body isn’t so great at repairing DNA damage, you can probably see how introducing radiation into the mix spells trouble.


One 2020 study from American researchers calculated that even A-T gene /carriers/ would have one third of the survival rate against a 2 Gray dosage of radiation compared to people who aren’t carrying that mutation.


The same vulnerability exists for lots of genetic syndromes associated with DNA repair mechanisms, putting those groups at big risks in a post-nuclear fallout. Even diseases that don’t seem to be related to DNA repair at all can put you in greater danger after a nuclear explosion.


The US Centers for Disease Control and Prevention estimates that about one in every 20 American adults has been diagnosed with heart disease, and nearly one in six have diabetes. As if having a bunch of healthcare facilities destroyed in a nuclear war isn’t bad enough, those conditions also make you more vulnerable to radiation.


Chronic conditions like heart disease and diabetes place a strain on your circulatory system, and create inflammation that your body has to deal with. And radiation /also/ turns out to be inflammatory.


You know how your body is mostly water? Well, the energy dumped into your body from radiation can break down those water molecules, creating super inflammatory free radicals. 


And too much inflammation proves to be pretty deadly.


One 2017 study by Japanese researchers in the “Journal of Radiation Research” found that heart diseases and diabetes could increase the risk of death from 1 Gray of exposure by anything from 60 to 160 percent!.


So there are a variety of diseases and syndromes that make you more vulnerable to radiation damage. And if you have any of those, you’re probably not going to be the last one standing. Sorry.


Things like aging and genetic conditions are out of your control. But it’s at least possible to make lifestyle changes that can reduce your odds of getting heart disease and diabetes in the first place, or at the very least, slowing their progression.


And one of those changes actually provides a protective effect against radiation all on its own: quitting smoking.


Inhaling a bunch of toxic gas into your lungs causes damage to your DNA and cells in a pretty similar way to radiation. Combining that with /actual/ radiation is, surprise surprise, /really/ bad. 


One study looking at nuclear power plant workers in the 20th century found that smokers were a whole /16.5/ times more likely to develop radiation-induced lung cancer than non-smokers. And, yes, they accounted for those lung cancer cases that were probably /just/ a result of smoking on its own. 


In other words, non-smokers will have a pretty strong advantage in a radioactive landscape.


But, however lucky you might be, a large enough dose of radiation is going to damage your body no matter who you are. 



On the upside, there’s no imminent sign of nuclear war as we’re making this video.


Should the future bring more radiation than present, the person likeliest to survive in the post-nuclear wasteland looks like a man, in his 20s or 30s, who doesn’t smoke, has no genetic disorders, and no other health conditions. 


If that’s you, congratulations. You won the nuclear lottery! Even so, I wouldn’t expect it to be all that pleasant.