(Many of you heard about this when it hit the news last October and I wrote this up to give my thoughts but then the fire died down considerably around it so I never published it. I revisited it the other day to check the status on the full report only to find it is still not out. I’ll keep you updated when it does get released if there’s anything worthwhile in it but thought it would be nice to share my thoughts nonetheless.)
Almost like clockwork, often conveniently close to Halloween, it’s time to scare people away from bacon, hot dogs and red meat. The World Health Organization recently released a report listing processed meats (bacon, salami, hot dogs) as cancer causing agents and red meat as a probable cancer causing agent. Bacon and hot dogs are Group 1 carcinogens, in the same category as cigarettes, tobacco and asbestos, meaning there is sufficient evidence of being cancerous. Red meat is listed as a Class 2A, possible carcinogen, meaning there’s evidence but it’s not strong enough to conclude. I love bacon like the next guy but if the WHO is listing it as a definite cancer causer… turn off the grill and get those bacon wrapped hot dogs in a biohazard bag! We’d be foolish to keep eating it, right???
But before we ban bacon, which has just seen a renaissance the last few years, might we be best served to take a step back and look at this situation on the whole? I think so.
Does Bacon Cause Cancer?
Bacon, just like beer and cigarettes, doesn’t always cause cancer, as evidenced by countless people who’ve indulged regularly without harm. Check out these centenarians who serve as a prime example that there’s no absolute in nutrition.
That’s great, you say, these are the lucky ones. But could it cause cancer in the rest of us not gifted with great genetics?
We don’t really know. This report says yes but instead of taking that at face value it benefits us all to dig a little deeper…
The report from WHO covered the October meeting of the IARC (International Agency for Research in Cancer), which will release a full report of the data soon but hasn’t been published officially yet, although it still appears to be a ways off. The basics from the IARC press release…
IARC Monographs evaluate consumption of red meat and processed meat
This two page summarizes that based off of the evidence available the IARC concluded that processed meats cause cancer and they think red meat might but they can’t be sure.
A more detailed report was published in the Lancet, which is free to view but requires you to register:
Carcinogenicity of consumption of red and processed meat
After reading that review, here are some notes:
1. The claim of carcinogen is mostly for colorectal cancer, although some studies reported red meat links to pancreas/prostate cancer while processed meat was linked to stomach cancer.
2. Red meat consumption and colorectal cancer association was found in 7 of 14 studies cohort studies and in 7 of 15 case control studies. That’s 14 of 29 that found a link and 15 that didn’t.
3. Processed meat and colorectal cancer association was found in 12 of 18 cohort studies and 6 of 9 case control studies. That’s exactly 2/3 of the cases.
4. The big finding via meta analysis was that every extra 100g of red meat per day increased the colorectal cancer risk by 17% and every 50g of extra processed meat increased the risk by 18%.
As always, keep in mind the severe limitations of nutrition research, led by the foundational flaw that most nutrition research is limited by nature because of how the data is primarily collected (i.e. tell me how much processed meat you eat on average a week this year, last year, etc.) and then matched to health outcomes (colorectal cancer occurrence).
Nutrition doesn’t take place in a vacuum. Other things impact nutrition. How do we know that the people who choose processed and/or red meat don’t eat an extra 20 grams of sugar a day, have a history with antibiotics, sleep a half hour less or have more stressful jobs? No matter how much researchers try to control for other variables it’s literally impossible to simplify nutrition at this point in time.
Web MD covered it very nicely:
Meat & Cancer: What’s the risk?
A great little article I suggest reading entirely but here is one of the big takeaways:
Each daily 50-gram portion of processed meats — about the size of an average hot dog — increases the risk of colorectal cancers by 18%, the report says. Each daily, 100-gram portion of red meat — about one-quarter of a pound — raises colorectal cancer risk by 17%.
In absolute terms, the increased risk is pretty small. For example, the risk that a man will get colorectal cancer during the course of his lifetime is about 4.8%, on average — or said differently, about 1 in 21 men will develop it in his lifetime. A 17% increase in that risk bumps it up to 5.6%, or changes that risk to about 1 in 18 men.
By comparison, a 2005 study determined that smoking a single daily cigarette could increase a person’s risk of lung cancer by about 200% to 400%.
So, if this is indeed correct and true, which we’re still not quite sure, then a man adding a hot dog a day to his diet raises his risk of developing colon cancer some time in his life from 4.8 to 5.6%. Why are we comparing that to cigarettes and asbestos, again?
Again, possibly most importantly, we still don’t have a clear mechanism. Meaning, we don’t know how it happens or why it happens. I wonder, with a difference this small and no mechanism, can we be sure it’s even really happening? Maybe it is but it reminds me a lot of the saturated fat, cholesterol and salt journey we’ve already been down.
Question: Why do we keep doing this to people? We don’t really know it for a fact, we just suspect. And we really want to find the ONE thing that’s bad so we can say, “Ah-ha! This is it! Processed meat! That is why we are getting sicker and fatter! Just cut that out and things will be fine. What? Oh no, it’s not the bun, french fries and 32 ounce soda, it’s the meat!”
There are a hundred reasons why people get sick and it’s not probably not processed meat, certainly not all by itself. We like to search for simple answers to our complex questions because it’s easier to say eliminate bacon instead of minding all the other things that contribute to health because tackling those is too big of an issue.
Here’s an interesting Q & A on the report from the WHO.
Once again, worth reading, but here’s 2 important takeaways:
- They are listing processed meats as “evidence supports causal link to cancer” which falls into the same category as tobacco and asbestos but that doesn’t mean it’s as dangerous.
- There is still very much that is unknown, particularly when you start looking for specifics and nuances into this issue. There is more unknown that known at the moment.
To me it’s a dangerous practice to put the blame on red meat and processed meat. We’ve already been down this road with fat, salt and cholesterol. Hot dogs might not be the “healthiest” thing on the planet but neither is the bun they come in or the chili and cheese often smothered on them or the soda on the side or the concept that they might be simply part of a calorie overload (which might be the biggest issue of all).
Let’s keep looking at the whole picture and focusing our efforts on the basic health improvement pursuits, not wasting time trying to figure out how to blame something specific for a general problem.
Thanks for reading, have a great day!
P.S. Could it be possible that the people eating all the processed and red meat have the worst diets and lifestyle? If so, what if eating read meat actually prevents them from having even worse health outcomes…?