Undoubtedly, earlier this week you heard that the World Health Organization’s International Agency for Research on Cancer (IARC) published a report that classifies processed meat as carcinogenic to humans and red meat as probable carcinogenic.
I am pretty sure you also have read some sensationalist titles such as “Processed meats rank alongside smoking as cancer causes – WHO” or “Processed meats do cause cancer – WHO”.
Does it meat really cause cancer and Why? Should we stop eating meat?
First of all, what processed meat and red meat are?
Red meat: beef, veal, pork, lamb, mutton, horse, and goat.
Processed meat: any meat that has been transformed through salting, fermentation, curing, smoking, e.g., hot dogs, hams, sausages, pastrami and cold cuts.
How did the IARC come up with these conclusions? What Group 1 and Group 2A are?
A team of 22 international experts from 10 countries evaluated data from over 800 studies of cancer risk in humans and found out that convincing evidence that processed meat causes cancer and they placed it in Group 1.
In the case of red meat, they found limited evidence so they placed it in the group of probable carcinogenic substances, Group 2A.
Cigarettes and asbestos are in the same group of processed meat (Group 1) but this doesn’t mean that smoking cigarettes is as risky as eating meat. So why they belong to the same group? Because the IARC classifies carcinogenic substances into groups based on the strength of scientific evidence rather than the level of risk.
What type of cancer is linked to red and processed meat?
Red Meat: Strong but limited evidence of causing colorectal cancer. Also pancreatic and prostate cancer.
Processed meat: Colorectal cancer. Evidence for a link with stomach cancer, but not conclusive.
Why red and processed meats are linked to cancer?
Scientists have been studying what makes red and processed meat carcinogenic but the process is not fully understood yet.
Red meat contains heme-iron, a component of hemoglobin. When it is broken down in our gut it forms a family of chemicals called N-nitroso compounds which are linked to cancer. Processing meat causes the production of carcinogenic chemicals such as N-nitroso compounds and polycyclic aromatic hydrocarbons. In addition, cooking red and processed meat at high temperatures can cause the production of other carcinogenic substances. Furthermore, red and processed meats contain high level of saturated fats which increase the risk of chronic diseases.
Should we stop eating meat?
Well, that’s not what the report says. Red meat contains iron, B vitamins, proteins and other nutrients so it’s important to include it in the diet. However, as everything, it’s important to consume it with moderation. After all, the dose makes the poison.
So, what’s the take-home message?
High consumption of processed and red meats can increase the risk of cancer, which is not news as the link between meat and cancer was known long before the release of this report. SO, what to do ? Well, as the World Cancer Research Fund International recommends, in order to prevent cancer, you should consume less than 500 g (18 oz) a week, very little if any to be processed.
Indeed, the findings published by the IARC reinforce what had been confirmed by numerous studies, a plant-based diet is healthier and helps people live longer and better.
For further information about red meats and cancer and cancer prevention, please click the links below.