Wow, I had no idea there is a 15X increase for endurance athletes. Make me want to dial down the running a bit, which make you wonder where the sweet spot is for distance training.
It's rare but can happen where long distance running causes ischemic colitis which is where on a long run enough blood is diverted from the large intestine that it damages the intestine long term. It isn't surprising to me that there's higher likelihood of colon cancer given this. It seems like repeated bouts of lower blood for the intestine on long runs has a cumulative impact and damages the colon even if it doesn't cause ischemic colitis.
It may be the damage of repetitive motion, it may be chemicals released into the bloodstream from endurance athletics. It may be something else. Without knowing the root cause, it's impossible to figure out the "sweet spot"
Could be a lot of things. Lots of long distance runners consume a lot of sugary gels to keep going. Not sure what the typical composition is, but likely lots of glucose and no fibre.
The marathon runners I know also seem to eat tons of junk food, they can get away with it from a weight perspective because a long run will burn it off, but it could have other consequences.
Point being: there's a lot about long distance runners that's quite different from other people.
i saw something recently that pointed to the fact that ultra runners end up with less blood in their guts while running for SO long its leading to cancers and such.
Which is way more than what original hunters and gatherers ever clock. They do move a lot, but not so much, and they alternate their activities a lot too (running, walking, resting, taking entire days off and just guarding their village).
We're not really optimized for this sort of extreme endurance and long-term development of serious pathologies is unsuprising.
You shouldn't so offhandedly assume a hunter-gatherer lifestyle couldn't lead to issues like increased risk of CRC, or that activities which lead to increased risk of CRC couldn't be what hunter-gatherers did. Evolution is neither fast nor perfectly precise. Plenty of animal populations have common health problems that simply weren't harmful enough to reproduction to be selected out, much less something rare and late-onset like CRC.
I don't assume anything. From what we know about health of the last surviving hunter-gatherers, they suffer significantly less from "diseases of civilization" when taken in proportion to their settled neighbours. Some of those diseases (such as high blood pressure or diabetes 2nd type) seem to be totally absent in them. Cancers do happen, but not as often.
This pattern is quite old. Already ancient Egyptians suffered from civilizational diseases much more than hunter-gatherers, especially the richer ones (heart attacks, gout, cancer).
I won't bother checking or disputing the accuracy of your factual claims, because it does not matter.
Colorectal cancer is not the same thing as high blood pressure, or type 2 diabetes, or any other cancer that isn't colorectal cancer. Diseases are not a monolith and you cannot assume low risk of some diseases means low risk of others. That is wild guesswork passed off as logic, like measuring the shadow your testicles cast on the wall and announcing it is 24.1 degrees Celsius. Ultra-marathon runners also have low risk of type 2 diabetes!
Do you have specific evidence that modern hunter-gatherers have low rates of colorectal cancer that cannot be explained by survivorship bias, screening, genetic differences, and all other confounders, and that they are representative of historical hunter-gatherers? No? Then you cannot confidently conclude that hunter-gatherers didn't experience elevated rates of CRC.
The graph showing risk factors in age groups 18-49 is interesting - obesity, "sugary drinks (>2/day)", and sedentary lifestyle (>2 hr TV/day) are each about 1.5-2x increase in risk factor. Obesity has roughly doubled over this time period, and people are more sedentary. What I could find about "sugary drinks" seems to indicate it hasn't changed much or even dropped slightly over this time. So obesity/sedentary lifestyle probably explains a lot of the increase (maybe not everything, but probably close; a 50% increase in population incidence, where a ~2x risk factor affected ~50% of the population would explain it.)
Obviously this is just anecdotal and you could still be correct, but the two celebrities the article cited (Chadwick Boseman and James Van Der Beek) don’t seem to fit that mold.
Excellent content. The delivery mechanism of the site cited is very polarizing! At the very least it’s generated a lot of opinions. If I think of the target audience used to TikTok engagements it makes a lot of sense. It’s swipey influenced and interactive. It breaks the back button oh well we have browser tabs right?
The web is best for me when experimental UX like this is tried out.
Something I've never seen in these analyses is drinking. Millennials are heavy drinkers. Both craft brews and cocktails were defining generational traits. Not everyone is a drinker but it appears they are heavy drinkers compared to other generations.
The theory behind the ultra marathoners is that extreme distance running disrupts the epithelial layer and microbiome in the gut. Wouldn't drinking have similar effects?
It’s more like, millennials got older and started drinking less (as happens), and Gen Z drinks different things like hard seltzer, and also drinks a bit less overall. Plus there were just way too many craft brewers making hoppy ipa to begin with.
Unfortunately, hoppy IPA seems to constitute the majority of the survivors. I have no interest personally in suffering through another hazy sour grapefruit triple ipa, but that seems to be about 90% of craft brewery output these days.
Well, your first Google result is a blog post that makes my point.
> For example, baby boomers are the generation with the most dramatic increase in harmful alcohol abuse. In contrast, Gen Z prefers the sober lifestyle as they are known to consume alcohol much less than any of their older counterparts, including millennials.
> Well, your first Google result is a blog post that makes my point.
It doesn't though? That specific quote you pulled says
- boomers have had a dramatic increase in alcohol abuse
- Gen z prefers sober lifestyle, drinking less than all cohorts, including millenials
If you scroll down past the intro paragraph, it says very directly:
"Although alcohol consumption is trending down among millennials, there are still high rates of alcohol consumption and misuse."
My point originally was that people waste our time when they raise questions that are very easily self-answerable. And you've proved that even further.
I’m in my early 30s and am starting to think about getting a screening. Problem is, it’s not trivial to do. You have to really upsell your doctor to get one so early, even though it’s a relatively benign procedure.
There is a noninvasive testing method called Shield but it is way too flawed to be reliable (with poor positive rates for malignant tumors)
If you tell your doctor that a parent had polyps removed (say, recently), that will give you your best chance of getting one. Most likely, if you're in an even remotely progressive area, your doc wants you to have one, but their hands are tied by the insurance company. Afaik you dont have to provide any proof of your claim re parental polyps.
> but their hands are tied by the insurance company.
Doctors' ability to prescribe or refer is never restricted by an insurance company. If they think a patient should get whatever healthcare, they are free to say it.
Lie about family history, but even colonoscopies are not perfect; I just had somebody in my family die of CRC because...
- They had symptoms and wanted a screening, but their PCP repeatedly denied them a referral for like a year because they were "too young".
- They lied about family history after symptoms got worse and got their referral.
- They got the colonoscopy which came back clean, and then symptoms continued to get worse.
- Finally their doctor gave them a referral for an MRI.
Results were stage 4 CRC. The doctor performing the colonoscopy missed the tumor, which was tucked into the sigmoid (the bend in your colon), where he didn't properly inflate because he wasn't taking it very seriously. It had a thumb-tip sized protrusion inside the colon but had gotten huge on the opposite side of the colon wall. They fought it for 8 years after the diagnosis and over 100 rounds of chemo (!!!), were about to get a new procedure at Yale, in which the doctor told them to think of it in terms of "this really may be a complete cure", but it was canceled because of the Big Beautiful Bill.
If you have symptoms (even if you don't), don't let some fuckass Nurse Practitioner tell you no. They don't know shit and they let their egos get in the way when they have to deal with moderately informed patients advocating for themselves. This was preventable and tge medicap system failed them because both the PCP and the doctor performing the colonoscopy were not paying attention to what they were being presented with and saw only their own expectations.
Also...apparently doctors wanted to lower the screening age to like 35, but insurance companies fought it, so it's at 45.
How much of the rise do the listed later on (endurance athletes, obesity, sugary drinks, sedentary lifestyle) explain the relative youth rise? After all, some of this was an issue in 2006 as it is in 2026. Does it explain most of the relative rise, or is there a major missing piece / a mystery still to be explained? I doubt the % of endurance athletes changed meaningfully population-wide, to be a major contributing factor, for example.
I had to have a good read of the article and put the content in ChatGPT for further more detailed analysis. I still can’t infer a single thing about how I should be surprised or how people’s habits changed, so feel free to enlighten me!
Food delivery is now an "essential" for more people than it ever was before. Doordash/Uber Eats is how a weirdly large amount of people eat in general.
The rate of increase in childhood obesity went up during covid.
If you screen more people for the disease, and do it better, such that you reduce the incidences and fatalities in the 50+ cohort, that improvement logically implies that you must be catching incidences in the under 50 cohort. So it's going to skew the numbers. Incidences that would have been tallied in the 50+ cohort, are now counted in the under 50.
E.g. a 45-year-old with a latent colorectal cancer who would previously not have been diagnosed early, but only late when they developed symtpoms, by which time they hit 50, would have counted as an incidence or a likely fatality, among the 50+ data. But if that same individual had been caught at 45, they would have counted as an incidence against int he under-50 cohort.
Earlier, better and more available screening alone will shift the data this way.
This mostly can't explain the fact that mortality is also rising in under 50s. It is true mortality is rising less than incident, and that a small proportion instances of mortality could be deaths related to reasonable risks taken on from treatment side effects (to make up numbers, it makes sense to take a 5% chance of dying from treatment this year over a 80% chance of dying from cancer in 5 years), but this is probably not the whole effect. Something is causing more CRC in people under 50.
Even in Czechia, where the combination of traditional "heavy" food and, probably, some sort of genetic burden (people with Czech ancestry tend to suffer from colorectal cancers even if they live in regions with very different diets) used to make us the record holders, mortality has gone significantly down.
Humanity seems to be getting this particular snake in its grip.
When I got my second, I had a bidet and it made a huge difference. That and a bit of vaseline to prevent too much irritation. It's an uncomfortable process so taking every win you can saves your sanity
I think they could do pretty well just not adding bubble gum or whatever nasty flavors the prep has. Sure it'll still be unpleasant and salty, but burping up that nonsense all day really doesn't make it better.
i disagree. content is great. hitting back button messes stuff up for me. a long form article is preferred for me but maybe this is better for people used to swiping.
I stopped after the 4th click, I found it irritating to have to click to get 1 or 2 sentences at a time. This would have been just fine as a short article, making it interactive annoyed me more than the revealed content informed.
My layman's thoughts are it has something to do with young people spending way too much time on the toilet sitting doomscrolling on their phones. (also yes to microplastics and endocrine disruptiors)
Also, hope that bidets may help with it in some way? Bidets supposedly reduce hemorrhoids.
It's rare to see a website that fails to display anything without JS being enabled that also has such nice looking code. I'm both disappointed and impressed! Reading between the script tags was enough to get the idea at least
> But that progress belongs almost entirely to people 50 and over. For people under 50, both incidence and mortality have been climbing. CRC is now the #1 cancer killer in men under 50.
You need to go to the 2nd screen "Split by age group"
You didn't actually click and read anything. Hank's page is saying exactly what the article you linked is saying. CRC is on the rise in young people. I'm not sure why the moderators changed the title of this post. It should be "Something is Going on with Colorectal Cancer."
Wow, I had no idea there is a 15X increase for endurance athletes. Make me want to dial down the running a bit, which make you wonder where the sweet spot is for distance training.
It's rare but can happen where long distance running causes ischemic colitis which is where on a long run enough blood is diverted from the large intestine that it damages the intestine long term. It isn't surprising to me that there's higher likelihood of colon cancer given this. It seems like repeated bouts of lower blood for the intestine on long runs has a cumulative impact and damages the colon even if it doesn't cause ischemic colitis.
It may be the damage of repetitive motion, it may be chemicals released into the bloodstream from endurance athletics. It may be something else. Without knowing the root cause, it's impossible to figure out the "sweet spot"
Could be a lot of things. Lots of long distance runners consume a lot of sugary gels to keep going. Not sure what the typical composition is, but likely lots of glucose and no fibre.
The marathon runners I know also seem to eat tons of junk food, they can get away with it from a weight perspective because a long run will burn it off, but it could have other consequences.
Point being: there's a lot about long distance runners that's quite different from other people.
i saw something recently that pointed to the fact that ultra runners end up with less blood in their guts while running for SO long its leading to cancers and such.
It's not simply endurance athletes though. It was 2x ultra-marathons >26 miles, or at least 5 marathons completed.
Which is way more than what original hunters and gatherers ever clock. They do move a lot, but not so much, and they alternate their activities a lot too (running, walking, resting, taking entire days off and just guarding their village).
We're not really optimized for this sort of extreme endurance and long-term development of serious pathologies is unsuprising.
You shouldn't so offhandedly assume a hunter-gatherer lifestyle couldn't lead to issues like increased risk of CRC, or that activities which lead to increased risk of CRC couldn't be what hunter-gatherers did. Evolution is neither fast nor perfectly precise. Plenty of animal populations have common health problems that simply weren't harmful enough to reproduction to be selected out, much less something rare and late-onset like CRC.
I don't assume anything. From what we know about health of the last surviving hunter-gatherers, they suffer significantly less from "diseases of civilization" when taken in proportion to their settled neighbours. Some of those diseases (such as high blood pressure or diabetes 2nd type) seem to be totally absent in them. Cancers do happen, but not as often.
This pattern is quite old. Already ancient Egyptians suffered from civilizational diseases much more than hunter-gatherers, especially the richer ones (heart attacks, gout, cancer).
I won't bother checking or disputing the accuracy of your factual claims, because it does not matter.
Colorectal cancer is not the same thing as high blood pressure, or type 2 diabetes, or any other cancer that isn't colorectal cancer. Diseases are not a monolith and you cannot assume low risk of some diseases means low risk of others. That is wild guesswork passed off as logic, like measuring the shadow your testicles cast on the wall and announcing it is 24.1 degrees Celsius. Ultra-marathon runners also have low risk of type 2 diabetes!
Do you have specific evidence that modern hunter-gatherers have low rates of colorectal cancer that cannot be explained by survivorship bias, screening, genetic differences, and all other confounders, and that they are representative of historical hunter-gatherers? No? Then you cannot confidently conclude that hunter-gatherers didn't experience elevated rates of CRC.
The graph showing risk factors in age groups 18-49 is interesting - obesity, "sugary drinks (>2/day)", and sedentary lifestyle (>2 hr TV/day) are each about 1.5-2x increase in risk factor. Obesity has roughly doubled over this time period, and people are more sedentary. What I could find about "sugary drinks" seems to indicate it hasn't changed much or even dropped slightly over this time. So obesity/sedentary lifestyle probably explains a lot of the increase (maybe not everything, but probably close; a 50% increase in population incidence, where a ~2x risk factor affected ~50% of the population would explain it.)
Obviously this is just anecdotal and you could still be correct, but the two celebrities the article cited (Chadwick Boseman and James Van Der Beek) don’t seem to fit that mold.
Excellent content. The delivery mechanism of the site cited is very polarizing! At the very least it’s generated a lot of opinions. If I think of the target audience used to TikTok engagements it makes a lot of sense. It’s swipey influenced and interactive. It breaks the back button oh well we have browser tabs right?
The web is best for me when experimental UX like this is tried out.
Something I've never seen in these analyses is drinking. Millennials are heavy drinkers. Both craft brews and cocktails were defining generational traits. Not everyone is a drinker but it appears they are heavy drinkers compared to other generations.
The theory behind the ultra marathoners is that extreme distance running disrupts the epithelial layer and microbiome in the gut. Wouldn't drinking have similar effects?
> Millennials are heavy drinkers.
That's news to millenials and the graveyard of craft breweries. I thought alcohol consumption is trending off for younger generations.
Millennials are not the younger generation anymore. That refers to Gen Z and alpha.
40% of the US population is older than 45, and millenial includes < 50th percentile.
We're also talking about alcohol consumption. Only half of Gen Z can drink and none of Alpha.
It’s more like, millennials got older and started drinking less (as happens), and Gen Z drinks different things like hard seltzer, and also drinks a bit less overall. Plus there were just way too many craft brewers making hoppy ipa to begin with.
Unfortunately, hoppy IPA seems to constitute the majority of the survivors. I have no interest personally in suffering through another hazy sour grapefruit triple ipa, but that seems to be about 90% of craft brewery output these days.
I hate to break it to you, but Millennials aren't a younger generation anymore...
though I'm not sure they drank any more than the 2-3 generations that proceeded them.
> but Millennials aren't a younger generation anymore...
Not younger than GenX/Baby Boomer? How?
Not to be rude but, google is free:
https://www.google.com/search?q=are+millenials+heavy+drinker...
Well, your first Google result is a blog post that makes my point.
> For example, baby boomers are the generation with the most dramatic increase in harmful alcohol abuse. In contrast, Gen Z prefers the sober lifestyle as they are known to consume alcohol much less than any of their older counterparts, including millennials.
> Well, your first Google result is a blog post that makes my point.
It doesn't though? That specific quote you pulled says
- boomers have had a dramatic increase in alcohol abuse
- Gen z prefers sober lifestyle, drinking less than all cohorts, including millenials
If you scroll down past the intro paragraph, it says very directly:
"Although alcohol consumption is trending down among millennials, there are still high rates of alcohol consumption and misuse."
My point originally was that people waste our time when they raise questions that are very easily self-answerable. And you've proved that even further.
I thought lots of data indicated that millennials were drinking less than previous generations?
I’m in my early 30s and am starting to think about getting a screening. Problem is, it’s not trivial to do. You have to really upsell your doctor to get one so early, even though it’s a relatively benign procedure.
There is a noninvasive testing method called Shield but it is way too flawed to be reliable (with poor positive rates for malignant tumors)
If you tell your doctor that a parent had polyps removed (say, recently), that will give you your best chance of getting one. Most likely, if you're in an even remotely progressive area, your doc wants you to have one, but their hands are tied by the insurance company. Afaik you dont have to provide any proof of your claim re parental polyps.
> but their hands are tied by the insurance company.
Doctors' ability to prescribe or refer is never restricted by an insurance company. If they think a patient should get whatever healthcare, they are free to say it.
Lie about family history, but even colonoscopies are not perfect; I just had somebody in my family die of CRC because...
- They had symptoms and wanted a screening, but their PCP repeatedly denied them a referral for like a year because they were "too young".
- They lied about family history after symptoms got worse and got their referral.
- They got the colonoscopy which came back clean, and then symptoms continued to get worse.
- Finally their doctor gave them a referral for an MRI.
Results were stage 4 CRC. The doctor performing the colonoscopy missed the tumor, which was tucked into the sigmoid (the bend in your colon), where he didn't properly inflate because he wasn't taking it very seriously. It had a thumb-tip sized protrusion inside the colon but had gotten huge on the opposite side of the colon wall. They fought it for 8 years after the diagnosis and over 100 rounds of chemo (!!!), were about to get a new procedure at Yale, in which the doctor told them to think of it in terms of "this really may be a complete cure", but it was canceled because of the Big Beautiful Bill.
If you have symptoms (even if you don't), don't let some fuckass Nurse Practitioner tell you no. They don't know shit and they let their egos get in the way when they have to deal with moderately informed patients advocating for themselves. This was preventable and tge medicap system failed them because both the PCP and the doctor performing the colonoscopy were not paying attention to what they were being presented with and saw only their own expectations.
Also...apparently doctors wanted to lower the screening age to like 35, but insurance companies fought it, so it's at 45.
How much of the rise do the listed later on (endurance athletes, obesity, sugary drinks, sedentary lifestyle) explain the relative youth rise? After all, some of this was an issue in 2006 as it is in 2026. Does it explain most of the relative rise, or is there a major missing piece / a mystery still to be explained? I doubt the % of endurance athletes changed meaningfully population-wide, to be a major contributing factor, for example.
You'd be surprised. COVID-19 fundamentally altered a lot of people's habits.
https://www.businessofapps.com/data/strava-statistics/
I had to have a good read of the article and put the content in ChatGPT for further more detailed analysis. I still can’t infer a single thing about how I should be surprised or how people’s habits changed, so feel free to enlighten me!
Food delivery is now an "essential" for more people than it ever was before. Doordash/Uber Eats is how a weirdly large amount of people eat in general.
The rate of increase in childhood obesity went up during covid.
One of Europe's leading nutrition experts also highlighted energy drinks in connection with the growing incidence of colon cancer among young people.
Sugary drinks is one of the cited contributers in this piece.
What evidence is there of that?
If you screen more people for the disease, and do it better, such that you reduce the incidences and fatalities in the 50+ cohort, that improvement logically implies that you must be catching incidences in the under 50 cohort. So it's going to skew the numbers. Incidences that would have been tallied in the 50+ cohort, are now counted in the under 50.
E.g. a 45-year-old with a latent colorectal cancer who would previously not have been diagnosed early, but only late when they developed symtpoms, by which time they hit 50, would have counted as an incidence or a likely fatality, among the 50+ data. But if that same individual had been caught at 45, they would have counted as an incidence against int he under-50 cohort.
Earlier, better and more available screening alone will shift the data this way.
This mostly can't explain the fact that mortality is also rising in under 50s. It is true mortality is rising less than incident, and that a small proportion instances of mortality could be deaths related to reasonable risks taken on from treatment side effects (to make up numbers, it makes sense to take a 5% chance of dying from treatment this year over a 80% chance of dying from cancer in 5 years), but this is probably not the whole effect. Something is causing more CRC in people under 50.
[delayed]
Years ago, I went to a show where Hank Green sang a song about his IBS. I still chuckle at the lyric about rerouting his bowel to a spigot.
That being said, I wish this was a normal page that scrolled. The click click click just breaks the web.
Even in Czechia, where the combination of traditional "heavy" food and, probably, some sort of genetic burden (people with Czech ancestry tend to suffer from colorectal cancers even if they live in regions with very different diets) used to make us the record holders, mortality has gone significantly down.
Humanity seems to be getting this particular snake in its grip.
If anyone here is up for disrupting the medical field: please come up with a colonoscopy-equivalent with a less awful prep experience.
When I got my second, I had a bidet and it made a huge difference. That and a bit of vaseline to prevent too much irritation. It's an uncomfortable process so taking every win you can saves your sanity
I think they could do pretty well just not adding bubble gum or whatever nasty flavors the prep has. Sure it'll still be unpleasant and salty, but burping up that nonsense all day really doesn't make it better.
By far the worst part. By far.
Though having to push out a huge fart at the request of the nurse while they stare at you when you wake up is a close 2nd.
Very effective way of conveying information.
I think a major factor is the increase in microplastics in our diets.
https://www.sciencedirect.com/science/article/abs/pii/S18777...
i disagree. content is great. hitting back button messes stuff up for me. a long form article is preferred for me but maybe this is better for people used to swiping.
I stopped after the 4th click, I found it irritating to have to click to get 1 or 2 sentences at a time. This would have been just fine as a short article, making it interactive annoyed me more than the revealed content informed.
Made even more annoying by the "next page" button constantly moving with the page height.
Very annoying UX, I found it felt like it was breaking continuity and making the ideas on each page disjointed.
My layman's thoughts are it has something to do with young people spending way too much time on the toilet sitting doomscrolling on their phones. (also yes to microplastics and endocrine disruptiors)
Also, hope that bidets may help with it in some way? Bidets supposedly reduce hemorrhoids.
It's rare to see a website that fails to display anything without JS being enabled that also has such nice looking code. I'm both disappointed and impressed! Reading between the script tags was enough to get the idea at least
Strange, because I've heard the exact opposite...
https://www.cbc.ca/news/health/colorectal-cancer-keeps-risin...
That is EXACTLY what the post is saying:
> But that progress belongs almost entirely to people 50 and over. For people under 50, both incidence and mortality have been climbing. CRC is now the #1 cancer killer in men under 50.
You need to go to the 2nd screen "Split by age group"
You didn't actually click and read anything. Hank's page is saying exactly what the article you linked is saying. CRC is on the rise in young people. I'm not sure why the moderators changed the title of this post. It should be "Something is Going on with Colorectal Cancer."