The evidence linking nitrates and nitrites to cancer(theguardian.com)
theguardian.com
The evidence linking nitrates and nitrites to cancer
https://www.theguardian.com/news/2018/mar/01/bacon-cancer-processed-meats-nitrates-nitrites-sausages
55 comments
It's my hope that we'll find a better, non-nitrate way to combat botulism. That's the only reason nitrates are added- cured meats can sometimes foster botulism.
Alternatively, I hope we might make a lucky discovery around gut flora. If bacteria in your digestive tract are digesting compounds in the cured meat & creating carcinogens, perhaps cultivating a different gut flora (e.g. through a predominantly plant-based diet) would be protective.
Yet a third option, from Wikipedia: Endogenous nitrosamine formation can be inhibited by ascorbic acid. In the case of formation of carcinogenic nitrosamines in the stomach from dietary nitrite (used as processed meat preservative), ascorbic acid markedly decreases nitrosamine formation in the absence of fat in the meal; but when 10% fat is present, this reverses the effect such that ascorbic acid then markedly increases nitrosamine formation.
So perhaps we will one day determine that a plate of bacon is unhealthy, while two slices of bacon (18g, 7g fat) plus an orange (150g, 0g fat, 50mg ascorbic acid) is actually perfectly healthy.
Alternatively, I hope we might make a lucky discovery around gut flora. If bacteria in your digestive tract are digesting compounds in the cured meat & creating carcinogens, perhaps cultivating a different gut flora (e.g. through a predominantly plant-based diet) would be protective.
Yet a third option, from Wikipedia: Endogenous nitrosamine formation can be inhibited by ascorbic acid. In the case of formation of carcinogenic nitrosamines in the stomach from dietary nitrite (used as processed meat preservative), ascorbic acid markedly decreases nitrosamine formation in the absence of fat in the meal; but when 10% fat is present, this reverses the effect such that ascorbic acid then markedly increases nitrosamine formation.
So perhaps we will one day determine that a plate of bacon is unhealthy, while two slices of bacon (18g, 7g fat) plus an orange (150g, 0g fat, 50mg ascorbic acid) is actually perfectly healthy.
>> It's my hope that we'll find a better, non-nitrate way to combat botulism. That's the only reason nitrates are added- cured meats can sometimes foster botulism.
Well, there's some evidence that nitrate-cured meats aren't safer from botulism than the alternative; and the evidence comes from the (British) meat industry itself:
An [internal report] written for the British meat industry reveals nitrites do not protect against botulism – the chief reason ham and bacon manufacturers say they use the chemicals.
The study, conducted for the British Meat Processors Association (BMPA) by the scientific consultancy Campden, and marked “confidential”, examines the growth of the toxin Clostridium botulinum in the processing of bacon and ham.
It is understood that the paper, seen by the Observer, was commissioned to provide evidence that nitrites, which have long been linked to cancer, are essential to protect consumers from food poisoning and, in particular, botulism, a potentially fatal disease. But, in what appears to be a major blow to the industry’s claims, the research found there was no significant growth of the bacteria in either the nitrite-free or the nitrite-cured samples that were tested.
The paper concludes: “The results show that there is no change in levels of inoculated C botulinum over the curing process, which implies that the action of nitrite during curing is not toxic to C botulinum spores at levels of 150ppm [parts per million] ingoing nitrite and below.”
https://www.theguardian.com/food/2019/mar/23/nitrites-ham-ba...
(edited out some sensationalist language in the quoted passage).
Well, there's some evidence that nitrate-cured meats aren't safer from botulism than the alternative; and the evidence comes from the (British) meat industry itself:
An [internal report] written for the British meat industry reveals nitrites do not protect against botulism – the chief reason ham and bacon manufacturers say they use the chemicals.
The study, conducted for the British Meat Processors Association (BMPA) by the scientific consultancy Campden, and marked “confidential”, examines the growth of the toxin Clostridium botulinum in the processing of bacon and ham.
It is understood that the paper, seen by the Observer, was commissioned to provide evidence that nitrites, which have long been linked to cancer, are essential to protect consumers from food poisoning and, in particular, botulism, a potentially fatal disease. But, in what appears to be a major blow to the industry’s claims, the research found there was no significant growth of the bacteria in either the nitrite-free or the nitrite-cured samples that were tested.
The paper concludes: “The results show that there is no change in levels of inoculated C botulinum over the curing process, which implies that the action of nitrite during curing is not toxic to C botulinum spores at levels of 150ppm [parts per million] ingoing nitrite and below.”
https://www.theguardian.com/food/2019/mar/23/nitrites-ham-ba...
(edited out some sensationalist language in the quoted passage).
Good to know! I find myself thinking of flame retardants in furniture. Most fatal house fires were started by smoldering cigarettes, and so flame testing of furniture is designed around these conditions. But smoking has plummeted in prevalence, while flame retardants have demonstrated all kinds of negative health impacts.
There are a number of vegetable sources of nitr{a,i}tes as well. A stick of celery has more (potassium IIRC) nitrate than a typical piece of salami has (sodium) nitrate. This is why celery juice is an ingredient in so-called "nitrate-free" cured products. They're not actually nitrate-free, they just use celery juice as a source instead of adding a pure powder, so they don't have to list "sodium nitrate" explicitly.
https://www.mcgill.ca/oss/article/food/celery-juice-viable-a...
https://www.mcgill.ca/oss/article/food/celery-juice-viable-a...
>> Colorectal is also one of most treatable, and curable cancers there are .
While I agree that the interesting statistic is "the individual chance of getting colorectal cancer given that one eats meats cured with nitrites and nitrates", I don't think I'd accept the risk to give up a piece of my colon for the joy of eating ham. Especially if this joy can be enjoyed without having to run the risk (see the bit about Parma ham in the article).
Btw, 5% risk is a gigantic chance. 5%! One in twenty! Where does that number come from? Can you link to its source please?
Edit: let me stress this again; it's not cured meats that increase the chance of colorectal cancer. It's meats cured with nitrates. You don't need to make a choice between a healthy colon and an enjoyable diet.
While I agree that the interesting statistic is "the individual chance of getting colorectal cancer given that one eats meats cured with nitrites and nitrates", I don't think I'd accept the risk to give up a piece of my colon for the joy of eating ham. Especially if this joy can be enjoyed without having to run the risk (see the bit about Parma ham in the article).
Btw, 5% risk is a gigantic chance. 5%! One in twenty! Where does that number come from? Can you link to its source please?
Edit: let me stress this again; it's not cured meats that increase the chance of colorectal cancer. It's meats cured with nitrates. You don't need to make a choice between a healthy colon and an enjoyable diet.
> 5% risk is a gigantic chance. 5%! One in twenty!
I can't tell whether or not you understand that 5% is supposed to be the base chance of getting colorectal cancer. Cancer in general is very common, we basically all get it eventually in some form or other. The difference nitrate processed meats are supposed to make is an 18% increase of that base 5%, moving 5% to 5.9% (this is why the article feels a little deceptive, because the correct interpretation of the statistic completely relies on the word "by" and a preexisting knowledge of the baseline statistic).
> I don't think I'd accept the risk to give up a piece of my colon for the joy of eating ham.
I'm not saying it's nothing, but to be clear the OP is suggesting the _absolute_ difference is 0.9%. So that is the additional risk you would be accepting over your lifetime for regularly eating it.
I can't tell whether or not you understand that 5% is supposed to be the base chance of getting colorectal cancer. Cancer in general is very common, we basically all get it eventually in some form or other. The difference nitrate processed meats are supposed to make is an 18% increase of that base 5%, moving 5% to 5.9% (this is why the article feels a little deceptive, because the correct interpretation of the statistic completely relies on the word "by" and a preexisting knowledge of the baseline statistic).
> I don't think I'd accept the risk to give up a piece of my colon for the joy of eating ham.
I'm not saying it's nothing, but to be clear the OP is suggesting the _absolute_ difference is 0.9%. So that is the additional risk you would be accepting over your lifetime for regularly eating it.
>> I can't tell whether or not you understand that 5% is supposed to be the base chance of getting colorectal cancer.
I suggest the following as an easy to make, strong interpretation of my comment: "5% chance is already pretty high and I would prefer to do nothing that increases it any further".
To clarify, that was the intepretation I had in mind when writing the comment (and still now).
Edit:
>> Cancer in general is very common, we basically all get it eventually in some form or other.
That sounds counterintuitive and from a cursory look at incidence statistics, it seems to be an exaggeration. e.g. Wikipedia says:
About 20% of males and 17% of females will get cancer at some point in time while 13% of males and 9% of females will die from it.[196]
https://en.wikipedia.org/wiki/Cancer#Epidemiology
I suggest the following as an easy to make, strong interpretation of my comment: "5% chance is already pretty high and I would prefer to do nothing that increases it any further".
To clarify, that was the intepretation I had in mind when writing the comment (and still now).
Edit:
>> Cancer in general is very common, we basically all get it eventually in some form or other.
That sounds counterintuitive and from a cursory look at incidence statistics, it seems to be an exaggeration. e.g. Wikipedia says:
About 20% of males and 17% of females will get cancer at some point in time while 13% of males and 9% of females will die from it.[196]
https://en.wikipedia.org/wiki/Cancer#Epidemiology
I over-rounded on the 5% number (since fixed), real stats are 4.3% for men and 4% for women and with an 18% increase that brings it to <5.07%, not 5.9%.
I've included the source in the comment as well.
I've included the source in the comment as well.
Thank you.
The biggest problem is that some people [typically on rural areas that have a traditional disdain for science], only have access to drinking water contaminated with nitrites from farms. For many people there is a chronic daily dose, even if they are vegans.
Well, there are some natural nitrates/nitrites in celery powder, which is generally what is used in more 'natural' processed meats.
Another point is that there's a sub-linear relationship between mortality rates and life expectancy. Intuitively, it seems like a 10% increase in mortality should cut your life expectancy from 81 to 73.
But in fact, it only cuts life expectancy by about 6 months. To meaningfully cut years off your life, you have to increase your mortality rate by hundreds of percent. E.g. smoking about triples all cause mortality.
Going the other way, this is the real challenge with life extension. To increase life expectancy by a decade would require lowering mortality rates by more than an order of magnitude.
But in fact, it only cuts life expectancy by about 6 months. To meaningfully cut years off your life, you have to increase your mortality rate by hundreds of percent. E.g. smoking about triples all cause mortality.
Going the other way, this is the real challenge with life extension. To increase life expectancy by a decade would require lowering mortality rates by more than an order of magnitude.
Thanks for this. Read this article few years ago and practically cut out bacon because of it.
How much does my cancer risk increase from alcohol?
How much does my cancer risk increase from alcohol?
I wonder why the conversation is all about avoiding nitrates and nitrites in bacon and never about avoiding celery, beets, radishes, chard, lettuce, spinach, etc. which contain far higher amounts.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6240834/
Nice table: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6240834/table/t...
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6240834/
Nice table: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6240834/table/t...
According to the article:
" After all, nitrate is naturally present in many green vegetables, including celery and spinach, something that bacon manufacturers often jubilantly point out. As one British bacon-maker told me, “There’s nitrate in lettuce and no one is telling us not to eat that!”
But something different happens when nitrates are used in meat processing. When nitrates interact with certain components in red meat (haem iron, amines and amides), they form N-nitroso compounds, which cause cancer. The best known of these compounds is nitrosamine. "
" After all, nitrate is naturally present in many green vegetables, including celery and spinach, something that bacon manufacturers often jubilantly point out. As one British bacon-maker told me, “There’s nitrate in lettuce and no one is telling us not to eat that!”
But something different happens when nitrates are used in meat processing. When nitrates interact with certain components in red meat (haem iron, amines and amides), they form N-nitroso compounds, which cause cancer. The best known of these compounds is nitrosamine. "
Perhaps a small irony, the nitrates in green vegetables & beets actually enhances athletic performance.
Yeah, I've only heard about nitrates in the context of red beet juice for long distance races. When trying to search about the merits of it, I was always confused about it being so heavily touted as both bad and good, but this explains it.
Please repeat this explanation but for me, a person who can't read.
I'll humor you- in short, nitrates are fine, but when combined with red meat you create new compounds that are harmful.
Not unlike how 6ppd in car tires seems safe, but when it reacts with ozone, the byproduct kills salmon.
Not unlike how 6ppd in car tires seems safe, but when it reacts with ozone, the byproduct kills salmon.
I remember reading that in the late 1950's the FDA limited the amount of nitrites in meat. And also required adding ascorbic acid. The idea is that when you cook meat treated with nitrites the ascorbic acid destroys the nitrite before they have a chance to form nitrosamines.
Might be that nitrites in uncooked vegies is fine.
Might be that nitrites in uncooked vegies is fine.
It is covered in the article that the problem is how it interacts with red meat.
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> But learning that consumption of processed meat causes an additional 34,000 worldwide cancer deaths a year is much more chilling.
I'm sorry but 34,000 worldwide deaths a year is literally nothing. The US has over 30,000 auto deaths per year. Around the world, there are over 1 million auto deaths per year.
If 34,000 deaths a year from processed foods is important, then there are many, many things that are a much easier way to save lives than getting rid of hot dogs and bacon.
I'm sorry but 34,000 worldwide deaths a year is literally nothing. The US has over 30,000 auto deaths per year. Around the world, there are over 1 million auto deaths per year.
If 34,000 deaths a year from processed foods is important, then there are many, many things that are a much easier way to save lives than getting rid of hot dogs and bacon.
You are trying to draw usefulness from the article but the point of the article is not to inform but to generate anxiety and with it ad revenue.
I remember reading a Cochrane Review meta-analysis confirming a link between processed meat consumption and recto-colon cancer, from memory this probably more than 10 years ago. None of this is new information.
I am all for reducing meat consumption but these 'informational' articles from the guardian and often even the bbc and nyt should be banned as low-value adding submissions.
Unless there are reporting about a recent major world event these sites have (in my opinion) no place in HN.
I remember reading a Cochrane Review meta-analysis confirming a link between processed meat consumption and recto-colon cancer, from memory this probably more than 10 years ago. None of this is new information.
I am all for reducing meat consumption but these 'informational' articles from the guardian and often even the bbc and nyt should be banned as low-value adding submissions.
Unless there are reporting about a recent major world event these sites have (in my opinion) no place in HN.
As stated in the article, the core problem is nitrates/nitrites. This isn't a bacon-specific problem. It's a problem in all cured meats - hot dogs, SPAM, salami, etc.
Fortunately, there's plenty of "uncured" bacon and hot dog options in grocery stores these days. You just have to read the packaging.
Fortunately, there's plenty of "uncured" bacon and hot dog options in grocery stores these days. You just have to read the packaging.
Note that lots of those products say "no added nitrites or nitrates except those naturally occurring" in other ingredients. And then one of the ingredients is celery powder, which is only added for its nitrates. It's awfully misleading packaging.
If you're eating bacon and it tastes like bacon, it's cured.
If you're eating bacon and it tastes like bacon, it's cured.
> If you're eating bacon and it tastes like bacon, it's cured.
In Northern Ireland there's a producer (Finnebrogue) which sells nitrite-free bacon (no, it doesn't contain celery - "adding nitrites from vegetable extracts for a technological function and/or as a preservative, is banned by the European Union") . It's pretty decent, tastes like bacon.
> The range replaces the nitrites commonly used to cure bacon and give them their recognisable colour with a Mediterranean fruit and spice extract it claims matches the shelf life of traditionally produced bacon and ham.
They seem to be mostly useless at preventing Botlusim anyway: https://www.theguardian.com/food/2019/mar/23/nitrites-ham-ba...
In Northern Ireland there's a producer (Finnebrogue) which sells nitrite-free bacon (no, it doesn't contain celery - "adding nitrites from vegetable extracts for a technological function and/or as a preservative, is banned by the European Union") . It's pretty decent, tastes like bacon.
> The range replaces the nitrites commonly used to cure bacon and give them their recognisable colour with a Mediterranean fruit and spice extract it claims matches the shelf life of traditionally produced bacon and ham.
They seem to be mostly useless at preventing Botlusim anyway: https://www.theguardian.com/food/2019/mar/23/nitrites-ham-ba...
>> It's pretty decent, tastes like bacon.
What I've found is that peoples' tastes develop according to what we usually eat, so "tastes like bacon" is different if you're used to eating meats cured with nitrites, than what it would be if you didn't.
I've said this story before on HN: in Greece, where I'm currently at, about 80% of the milk in supermarket refrigerated isles is UHT (Ultra Heat Treated). UHT milk doesn't need to be stored in a refrigerator, in fact that's the whole point. But, I guess, they [1] put it there so people will buy it thinking it's "fresh" (i.e. low-heat pasteurised and about a week old). The fact that so much of the milk sold in supermarkets is UHT -and so little is "fresh"- tells me that it basically works and people buy it.
The interesting thing is that, if you ask Greeks whether they prefer "fresh" milk or UHT milk, the chances are they'll tell you they prefer "fresh" milk. There was a study at some point -sorry that I don't have a reference- that said I think that consumers around the EU, including Greeks, prefer "fresh" milk.
Conclusion: at least Greeks drink UHT milk and have no idea it's UHT.
... even though it tastes distinctly unlike fresh milk.
They're probably used to the taste and think that's what fresh milk tastes like. And don't let me get started on how most "fresh" milk doesn't taste of anything...
____________
[1] "They" is the dairy industry that ask for it - and the supermarkets that don't care and comply.
What I've found is that peoples' tastes develop according to what we usually eat, so "tastes like bacon" is different if you're used to eating meats cured with nitrites, than what it would be if you didn't.
I've said this story before on HN: in Greece, where I'm currently at, about 80% of the milk in supermarket refrigerated isles is UHT (Ultra Heat Treated). UHT milk doesn't need to be stored in a refrigerator, in fact that's the whole point. But, I guess, they [1] put it there so people will buy it thinking it's "fresh" (i.e. low-heat pasteurised and about a week old). The fact that so much of the milk sold in supermarkets is UHT -and so little is "fresh"- tells me that it basically works and people buy it.
The interesting thing is that, if you ask Greeks whether they prefer "fresh" milk or UHT milk, the chances are they'll tell you they prefer "fresh" milk. There was a study at some point -sorry that I don't have a reference- that said I think that consumers around the EU, including Greeks, prefer "fresh" milk.
Conclusion: at least Greeks drink UHT milk and have no idea it's UHT.
... even though it tastes distinctly unlike fresh milk.
They're probably used to the taste and think that's what fresh milk tastes like. And don't let me get started on how most "fresh" milk doesn't taste of anything...
____________
[1] "They" is the dairy industry that ask for it - and the supermarkets that don't care and comply.
It seems this is more common in the US than in Europe, for now:
The meat has been cured with nitrites extracted from vegetables, a practice not permitted by the European Commission because of evidence that it increases the risk of bowel cancer. But it is allowed in the US, where the product is often labelled as “all natural”. The powerful US meat industry is likely to insist that the export of nitrite-cured meat is a condition of a post-Brexit UK-US trade deal, which the UK government is under intense pressure to deliver.
https://www.theguardian.com/world/2021/feb/14/uk-us-brexit-t...
The meat has been cured with nitrites extracted from vegetables, a practice not permitted by the European Commission because of evidence that it increases the risk of bowel cancer. But it is allowed in the US, where the product is often labelled as “all natural”. The powerful US meat industry is likely to insist that the export of nitrite-cured meat is a condition of a post-Brexit UK-US trade deal, which the UK government is under intense pressure to deliver.
https://www.theguardian.com/world/2021/feb/14/uk-us-brexit-t...
Read the packaging closer. Most of the "uncured" meats use concentrated celery salt which is a strong source of nitrates. They do this so that they can still "cure" the meat, just "naturally". At the end of the day, if the package says "uncured" but the back says made with celery salt, its just marketing
Most, maybe all, of those options (at least in Canada where I live) also use nitrates, just from e.g. Celery extract. So you also have to know about that trick and look for it.
[deleted]
One source I learned about recently is sandwich meats like packaged deli turkey & chicken. I should have known better, but I didn't realize they are cured just like salami, bacon, etc.
Be careful, a lot of the “uncured” or “no added nitrites” have fine print that say “except those found in celery salt”, which is a natural source of nitrites
I think a big lesson of the COVID era is that people care about this kind of thing - statistical mortality - a lot less than you'd expect.
And conversely that many people are willing to give up quality of life, perhaps indefinitely, to decrease risk. To state the obvious, there’s an inherent tension in the fact that some of the things that make life pleasurable increase the chances of cutting that life short. People reach different conclusions about how to strike the balance, and I don’t think there’s one right answer.
> People reach different conclusions about how to strike the balance, and I don’t think there’s one right answer.
Yes Certainly. For instance if my dad had died of covid the decrease in my quality of life from that would have been permanently effected. Where yours had, your quality of life would be unchanged.
Yes Certainly. For instance if my dad had died of covid the decrease in my quality of life from that would have been permanently effected. Where yours had, your quality of life would be unchanged.
I think it's mainly been an experiment in how much the average person will limit their own pursuit of happiness for the sake of lowering the mortality risk of others.
The answer appears to be: to some extent, but there are limits. And I don't think that's new information. People do things all the time that involve some risk to others. They're more careful about risks to themselves and their families, but there are still limits.
Anyone who smokes cigarettes or sometimes drives under the influence (massive numbers of people) already demonstrated that they're willing to inflict much higher degrees of risk on themselves and others than being lax on covid protocols would entail.
The answer appears to be: to some extent, but there are limits. And I don't think that's new information. People do things all the time that involve some risk to others. They're more careful about risks to themselves and their families, but there are still limits.
Anyone who smokes cigarettes or sometimes drives under the influence (massive numbers of people) already demonstrated that they're willing to inflict much higher degrees of risk on themselves and others than being lax on covid protocols would entail.
> But learning that consumption of processed meat causes an additional 34,000 worldwide cancer deaths a year is much more chilling. According to Cancer Research UK, if no one ate processed or red meat in Britain, there would be 8,800 fewer cases of cancer. (That is four times the number of people killed annually on Britain’s roads.)
Is this trying to say that 23% of worldwide cancer deaths due to meat eating are in the UK?
Or is this just shitty writing?
Is this trying to say that 23% of worldwide cancer deaths due to meat eating are in the UK?
Or is this just shitty writing?
I can't speak to what they actually mean, but not all of the 8800 British cancer cases will die from cancer, so I guess you missed that difference in the sentence.
Right, the most sympathetic reading of that paragraph I can think of is that they're intentionally grouping numbers of cases and comparing them to numbers of deaths to be intentionally misleading about the scale of the problem.
It reads like they're just vomiting statistics to try to scare the reader.
[deleted]
I was a bit curious about nitrate/nitrite sources and I was surprised to find them in everyday foods including vegetables. After some Google searches, fermented veggies do have less nitrate/nitrite content when compared to their raw counterpart. Cheers to Kimchi and Sauerkraut!
Except Kim Chi has been linked to gastric cancer: https://en.goodtimes.my/2019/06/04/eating-kimchi-increases-t...
So less colon cancer, more stomach cancer.
So less colon cancer, more stomach cancer.
Interesting, the reseachers were from Chungbuk Univ. too. I guess with everything, moderation is also key. Colonoscopies are pretty common in Korea so in general, you’ll catch more adenomas early on if you’re Korean. The docs in the US hardly send people to do colonoscopies and will give you a CT at best.
So less colon cancer could be due to early intervention and snipping of adenomas.
So less colon cancer could be due to early intervention and snipping of adenomas.
I stay away form processed meats as a genetal rule. I used to love processed meats when growing up especially lunchon pork meats, weiners, saussages and salamies but I almost stopped eating these altogether. I still do but very rarely and I think it’d be better to eat less of processed foods in general. Over the years I started lowering my food portions such that Im not full when finishing a meal, the satiety feeling follows shortly after. This has had very good effects on my stomach in particular
Call me crazy but I've never considered eating bacon "safe" in as much as I considered eating a Ribeye "safe". Also who are these mythological deep bacon state actors convincing everyone eating bacon is safe? I question the premise of the subtitle. I went deep into the article searching for clues, but all the only substance there was some squabbles around nitrite based curing versus traditional salt curing.
Wow smokers went from 42% to 14%?! I knew I noticed fewer smokers but had no idea it was that dramatic.
edit: ahh the 42% stat was from 1965, not 1999 like the rest of the information.
edit: ahh the 42% stat was from 1965, not 1999 like the rest of the information.
That data makes it seem that cancer is highly associated with corpulence.
I always thought Francis Bacon was a decent chap. The artist, that is.
That doesn't mean your chance of cancer is 18%, that means your chance of that type of cancer goes from below 5% (4.3% for men, and 4% for women)[1] to <5.07%. A change of at the most .9% difference risk. Colorectal is also one of most treatable, and curable cancers there are.
And this isn't just bacon, this is for all processed meats, to reduce your chance you would have to eliminate all processed meat for a reduction of less than 1% in your chance at that specific type of cancer. I hate to compare anything to tobacco, but smoking tobacco increases your risk of cancer not by 18%, but 2,500%.
To quote a Wired article on this very topic that keeps getting rehashed [2]:
> The IARC is an organization of scientists, not policy makers. It publishes monographs to identify hazards and sift them into five piles: group 1 (carcinogenic), group 2A (probably carcinogenic), group 2B (possibly carcinogenic), group 3 (not classifiable), and group 4 (probably not carcinogenic.) Group 1 includes processed meat, and also asbestos. Also alcohol (boo!) and sunlight (yup!). Identifying hazards involves looking at existing data—lots and lots of it—to do essentially a meta-analysis of studies already out there. And it’s relatively objective. “Hazard identification is the process that is the closest to the generation of scientific data,” say Paolo Boffetta, a cancer epidemiologist at Mount Sinai who has served on similar WHO panels. In other words, IARC studies the studies and generates numbers.
> What the IARC doesn’t do—and where things get a lot fuzzier—is risk assessment, or figuring out the danger to humans in the real world.
[1] https://www.cancer.org/cancer/colon-rectal-cancer/about/key-...
[2] https://www.wired.com/2015/10/who-does-bacon-cause-cancer-so...
Edit: Added source for cancer risk and fixed my rounding mistake (5.9% -> 5.07%)