So many people I speak to tell me that meat causes cancer. I’ve always found it hard to believe considering we’ve been chowing down on this highly nutritious food for millions of years. So, I wanted to look into where this common notion came from and how true it is.
Where did the claims come from?
In October of 2015, the World Health Organization (WHO) released a paper called ‘Carcinogenicity of consumption of red and processed meat’. They also released a press release here and a simple Q&A article here. And then the NHS followed up with their summary here.
The press release stated:
After thoroughly reviewing the accumulated scientific literature, a Working Group of 22 experts from 10
countries convened by the IARC Monographs Programme classified the consumption of red meat as
probably carcinogenic to humans (Group 2A), based on limited evidence that the consumption of red meat
causes cancer in humans and strong mechanistic evidence supporting a carcinogenic effect.
This association was observed mainly for colorectal cancer, but associations were also seen for
pancreatic cancer and prostate cancer.
Processed meat was classified as carcinogenic to humans (Group 1), based on sufficient evidence in
humans that the consumption of processed meat causes colorectal cancer.”
The carcinogenic groups are as follows:
• Group 1 – Carcinogenic to humans
• Group 2A – Probably carcinogenic to humans
• Group 2B – Possibly carcinogenic to humans
• Group 3 – Not classifiable as to its carcinogenicity to humans
Firstly we need to understand the processes as to how the ‘very clever people’ come to these conclusions.
Zoe Harcombe explains this thoroughly here. But (very) basically, there are some studies that prove causation. These prove without a question that for example, smoking causes lung cancer.
Then, there are other studies that prove associations. These show a link between one thing and another, for example, yellow fingers are associated with lung cancer.
It’s really important to understand that associations do not prove causation. Associations are simply that, when some people do ‘x’, we notice ‘y’ seems to happen to many of those people.
No matter how strong the association, causation can not be claimed. When an association is observed, further studies should be carried out to prove the hypothesis.
With this knowledge in mind, let’s look at the evidence.
So, red meat probably gives us colorectal cancer and probably maybe gives us pancreatic and prostate cancer, all based on ‘limited evidence’. If it probably gives us cancer, then that could also mean there is a probability it does not.
The explanation given on the Q&A states…
“In the case of red meat, the classification is based on limited evidence from epidemiological studies showing positive associations between eating red meat and developing colorectal cancer as well as strong mechanistic evidence.
Limited evidence means that a positive association has been observed between exposure to the agent and cancer but that other explanations for the observations (technically termed chance, bias, or confounding) could not be ruled out.”
Epidemiological studies can only be associational in their nature, they even use the word association, so they cannot claim causation, which they don’t by using the word ‘probably’.
The Q&A also states “Eating meat has known health benefits.” As if this wasn’t confusing enough already… Meat is healthy but also gives us cancer (maybe).
Perhaps there’s a dose-response, if we limit our meat consumption we may get the health benefits while limiting our cancer risk? Their response to this…
“The risk increases with the amount of meat consumed, but the data available for evaluation did not permit a conclusion about whether a safe level exists.”
“The cancer risk related to the consumption of red meat is more difficult to estimate because the evidence that red meat causes cancer is not as strong. However, if the association of red meat and colorectal cancer were proven to be causal, data from the same studies suggest that the risk of colorectal cancer could increase by 17% for every 100-gram portion of red meat eaten daily.”
Can this get any more woolly? I’m literally more confused now than when I started looking into this. Let’s give up on this one and look into processed meats.
The WHO has stated without a doubt that processed meat causes colorectal cancer with the Q&A stating…
“This category [group 1] is used when there is sufficient evidence of carcinogenicity in humans. In other words, there is convincing evidence that the agent causes cancer. The evaluation is usually based on epidemiological studies showing the development of cancer in exposed humans.
In the case of processed meat, this classification is based on sufficient evidence from epidemiological studies that eating processed meat causes colorectal cancer.”
To make such a certain claim, there must be at least one randomised control study carried out at some time to have proved the claims. Er, no!
As stated, the evidence came from epidemiological studies that can only prove an association. So, they can not state for absolute certainty that processed meat causes colorectal or any other cancer until properly studied, no matter how strong the association.
Again, the case against processed meat is not absolute, they are educated guesses at best.
Epidemiological studies are surveys carried out on groups of people that be will asked questions about diet and health issues. Some tests are carried out like blood tests, blood pressure etc. These people will be followed for ‘x’ amount of years, then ‘very clever people’ will review the data and find associations.
There are a few issues with this, for instance, can you remember exactly what you’ve eaten over the last day, week or, in some cases, a year? How many grams of rib eye or prosciutto did you eat last Thursday?
There’s also the healthy person confounder. Meat has gotten a bad rap over recent years, so someone who cares for their own health and wellbeing would follow guidance from organizations such as the WHO. They would limit their meat, eat plenty of fruit and vegetables, steer clear of processed crap, not smoke, drink little alcohol, exercise regularly and maybe even meditate.
The opposite would be true for the person who cares little for their own health and cares only for pleasures and good times…
…They’ll smoke, drink, dodge the gym and eat anything including… Yes, the evil, cancer-causing meat. They just don’t care, because… “You’ve got to enjoy life, right? Otherwise, what’s the point of living?”
As I’m sure you can see, when these surveys are carried out, the fun-loving, meat guzzlers among us, are more likely to end up with all sorts of health complications. Much more than those that look after themselves.
So, these ‘very clever people’ look at the resulting data and notice that most of these people here – who got colorectal cancer – eat meat and processed meat (and drink and smoke and don’t exercise and eat any crap).
I imagine it goes something like this:
• Processed meat – 2 + 2 = 10+/- (close enough)
• Red meat – 2 + 2 = 152+/- (close, but not close enough to be certain)
If the assumptions are correct and we can get cancer, what numbers are we talking here? From the Q&A…
“According to the most recent estimates by the Global Burden of Disease Project, an independent academic research organization, about 34,000 cancer deaths per year worldwide are attributable to diets high in processed meat.
Eating red meat has not yet been established as a cause of cancer. However, if the reported associations were proven to be causal, the Global Burden of Disease Project has estimated that diets high in red meat could be responsible for 50,000 cancer deaths per year worldwide.”
Processed meat = 34,000 deaths globally (probably/maybe)
Red Meat = 50,000 deaths globally (possibly, not sure)
Global population according to Worldometer at time of writing = 7,792,675,496
This equates to:
• Processed meat = 1 in 229,196 people will die of cancer, or 2.5 times the capacity of Wembley Stadium.
• Red meat = 1 in 155,853 people may possibly die of cancer, or 1.7 times the capacity of Wembley Stadium, or very slightly worse odds than getting 5 numbers in the Lotto.
The Q&A even goes on to compare the numbers to cancer deaths by smoking, alcohol consumption and air pollution…
“These numbers contrast with about 1 million cancer deaths per year globally due to tobacco smoking, 600 000 per year due to alcohol consumption, and more than 200 000 per year due to air pollution.”
Don’t get me wrong here, I’m not saying that unnecessary deaths shouldn’t be avoided, but looking at it in this light puts it in perspective. It’s a mere drop of Jello in a cauldron of bone broth.
To add to the confusion, they then go on to state…
“The consumption of processed meat was associated with small increases in the risk of cancer in the studies reviewed. In those studies, the risk generally increased with the amount of meat consumed. An analysis of data from 10 studies estimated that every 50-gram portion of processed meat eaten daily increases the risk of colorectal cancer by about 18%.”
Taken on face value, an 18% increase in risk for every 50-gram portion per day sounds devastating. But this is an example of how numbers are twisted for dramatic effect.
18% is a relative risk number as opposed to absolute risk. The problem is that we need to know what the number is relative to. As – in this case – we do not know I can’t use this as an example, so I’ll make one up for entertainment value.
Let’s say 1 in 100 people get cancer without eating processed meat.
And, this increased to 2 in 100 when 50g of processed meat eaten per day.
Absolute risk is 1 in 100 vs. 2 in 100 or a 1% increase in risk – that doesn’t sound bad at all.
Relative risk is 1 vs. 2 or a 100% increase in risk – now that’ll make the front cover.
Taking this into consideration, an 18% increase in relative risk doesn’t tell us anything without knowing the original number. If we use, say, 50 in 100,000, then an 18% increase would be 9 giving us 59 in 100,000.
Unfortunately, relative risk is used all too often manipulating the layperson into believing something is much worse than it really is. I personally think it’s criminal and should be outlawed, but for whatever reason beyond my comprehension, it’s not.
With Headlines such as…
‘Processed meat ranks alongside smoking as major cause of cancer, World Health Organisation says’ – The Telegraph
‘Just two rashers of bacon a day raises your risk of cancer: Health chiefs put processed meat at same level as cigarettes’ – Daily Mail
‘Processed meats rank alongside smoking as cancer causes – WHO’ – The Guardian
…it’s understandable that many health-conscious people limited or even stopped eating processed and red meat. This dramatically affecting the sale of meat hitting our farmers hard. And, undoubtedly impacting the health of many people.
The media have jumped on the association with smoking. This is because both processed meat and smoking are in the same carcinogenic group (group 1). This sounds damning, but is explained further in the Q&A…
“processed meat has been classified in the same category as causes of cancer such as tobacco smoking and asbestos (IARC Group 1, carcinogenic to humans), but this does NOT mean that they are all equally dangerous. The IARC classifications describe the strength of the scientific evidence about an agent being a cause of cancer, rather than assessing the level of risk.”
Another example of things being blown out of proportion.
Summary of the WHO Recommendations
The assertions that processed meat is carcinogenic is weak. They cannot claim causation, and they should not, yet they do and people listen, take it as fact and act accordingly.
The link between red meat and cancer is even weaker and should be classed as inconclusive and left at that, with further studies required. Red meat shouldn’t be put into any carcinogenic group risking the health of those that believe this advice to be true and reduce or eradicate red meat from their diet as a result.
Evidence For Meat
The study is called ‘Dietary factors and risk of colon cancer: a prospective study of 50,535 young Norwegian men and women.’ It was on 50,535 Norwegian men and women aged 20-54 between 1977 and 1983.
“this prospective study provided no evidence of association between intake of meat, fish, fat, energy, fibre or calcium and risk of colon cancer, although an increased risk with frequent consumption of sausages was suggested.”
This is an associational type of study, so a lack of association speaks volumes where an association can only trigger an “ah, that’s interesting”, and further investigations would need to be carried out to know if it is true.
This made me wonder if there are any other studies on this subject?
“In conclusion, the state of the epidemiologic science on red meat consumption and CRC is best described in terms of weak associations, heterogeneity, an inability to disentangle effects from other dietary and lifestyle factors, lack of a clear dose-response effect, and weakening evidence over time.”
“Because of these limitations in the existing literature, there is currently insufficient evidence to confirm a mechanistic link between the intake of red meat as part of a healthy dietary pattern and colorectal cancer risk.”
“Low- to very-low-certainty evidence suggests that diets restricted in red meat may have little or no effect on major cardiometabolic outcomes and cancer mortality and incidence.”
These were on the first page of 10 results on PubMed out of 59 on a search for Colorectal Cancer and Meat, filtered for humans, meta-analysis and systematic reviews.
It amazes me how all these ‘very clever people’, spending ridiculous amounts of money on these studies, can end up with completely different conclusions.
When someone like the WHO commits and makes suggestions based on educated guesses, what happens if they get it wrong?
What happens when hundreds of thousands or even millions of lives are negatively affected by their wrong advice?
Why can such risks be taken on inconclusive evidence without proper studies to prove causation be taken?
…The cost of such studies is vast but would surely be less than the financial burden on the health care system following the negative effects on our health.
I know this is a simple view and life is just not that straight forward. But, the more I look into these kinds of subjects, the crazier I realise this world is. We have such faith in the advice we’re given and the truth is that it could be… Well… Wrong!
So wrong that our health and the health of our loved ones are at risk.
Keep It Simple
I believe we should disregard the confusing, twisted BS spoon-fed to us from the media.
And, we should question the advice given to us from the likes of the World Health Organization or Public Health England before taking it on board.
We should use a bit of common sense.
I’ve ranted about this here. Before this modern crazy world that we live in now, what would’ve been the only thing available to us to eat?
Simple, animals and some seasonal fruit and vegetables… And that’s it… Simple.
We’ve survived for millions of years eating this way. Our bodies have been finely tuned by Mother Nature to thrive from this highly nutritious food that this earth provides for us.
When I see a statement that red meat may give us cancer, it makes me realise how much we have lost touch with reality. It is such a stupid statement… Just as stupid as saying yellow fingers gives us lung cancer.
Before, we had to protect ourselves from sabre tooth tigers, now its these ridiculous recommendations from people we are supposed to trust, and many do.
The only time meat may be bad for us is when the animals are pumped full of steroids or antibiotics or any other un-natural crap.
Let’s keep it simple people, eat real food, whole food, food that our ancestors would’ve eaten.
Have a nutritious day!
There you have it! Just a reminder that I’m no doctor, dietitian or any other profession for that matter. I’m simply a bearer of information for you to do what you want with; question it, research it, erase it from your mind, you are in charge of you.