FUEL: 11/6/15 Meat as a Carcinogen - Relative Risk & Total Exposure

Relative Risk and Total Exposure

In case you haven't heard (maybe you went off the grid?) - processed meat has recently been classified as a carcinogen by the World Health Organization (WHO).....and what a story it has become.  Some cheered, some groaned and many put up the caution flag.  Now, if you've been reading these blog posts for a while you know that we are pretty big proponents of the simple dietary advice to "eat more plants".  After all, many different studies have shown that total plant consumption is linked to better health.  Whether it be the beneficial connection with prevention of vessel disease or the growing evidence that foods which trigger inflammation (including processed meat) are tied to diabetes or even the connections made between things like poor quality diet and anxiety/depression, it shouldn't be ignored.  In fact, a recent study showed that participants, especially women, who consumed the greatest number of fruits and veggies per day when they were young (9 servings had the most powerful effect) had the lowest levels of calcified plaque on tests done even 20 years later.

So why then was there so much backlash in the media when the WHO said that sufficient evidence existed to classify processed meat as a carcinogen?  In short, because, for many reasons, there probably should be.  In absolute terms, their statement is correct.....the evidence IS there, but it's a bit more nuanced than that.

For most folks, since we are exposed to many different risks every day, it's a question of relative risk and total exposure. For example, since the evidence of a link is strong enough to be considered causal (as per the experts who evaluated the research), it is accurate to say that processed meat consumption is a cause of cancer, the definition of a carcinogen.  Of course, the same can be said for smoking.....making it accurate to say they are the same.....they are both carcinogens.  However, and equally true, when compared to smoking, under typical exposures, smoking has a stronger link and is therefore a much higher RELATIVE risk. So, on a spectrum of known carcinogens, smoking would rank much higher....making it accurate to say that they are not the same....since the result largely depends on the exposure to the known risk.

Take for example the risk of an asteroid impact with earth:  Officially it IS a risk (with odds of about 75 million to 1) and so, by definition, it is the same as exposure to forces of nature (which sits at about 200,000 to 1) and heart disease (467 to 1). Yet, clearly, with such wildly different odds, the likelihood is very different.

So, even though smoking (leading to estimated 1 million cancer deaths per year) is a far riskier behavior than eating processed meat (leading to an estimated 34,000 cancer deaths per year) they are both carcinogens. In relative terms however, even though it is possible that with enough exposure, such as a person who eats low quality processed meat several times a day, compared to a person who had 1 puff of cigar to celebrate the birth of a friend's baby (not sure if that tradition still exists), it is a less potent risk.

Although I'm sure there will be continued developments in this and similar stories, with any luck the WHO classification story had the effect that any controversial topic can....it got us thinking and talking about it; because the more we do of that, the more likely we are to use evidence to formulate personal strategies to minimize the risks we face.

So although you won't hear us saying it's time to trade in that bacon for a smoking habit, you also won't hear us recommend you ignore the risks we face -- Low risk doesn't mean no risk -- with enough exposure, even low risk activities can generate big problems.  This is true in safety, this is true in health and, as unfortunate as it may seem for the bacon lovers.....it's true for food choices. The body is not a weak machine, if we give it what it needs (MOVE, FUEL, RECOVER,ENDURE, CONNECT), it will work well for many years......