One can and should simplify scientific research to make it intelligible, but there is a level of imprecision beyond which simplification becomes mere fiction. I think at this point, in most cases, saying something “causes cancer” is effectively fiction. It wasn’t always, but that phrase has been so abused that it now creates a one-to-one link in the popular imagination between the item of the week and our most potent medical boogeyman.
The recent announcement by the IARC (International Agency for Research on Cancer) and the associated statements by the WHO (World Health Organization) have created a current hullabaloo over red meat, and processed red meat in particular. If you want a good summary of that issue, please read this one, and not any of the more sensationalized pieces exploding into your news feeds.
Because those sensationalized pieces dominate. Most of the media are busily reporting, nuance-free, how red meat and processed meat “causes cancer.” Most are using the most inflated statistic—an increase in risk of 17%. Most are not mentioning baseline risk. Most are not discussing potency. Most are not mentioning that this information is not new, but instead a result of slowly progressing scientific research.
In my view, reporting that something “causes cancer” gives you all the panic with none of the information. What is the baseline risk? In this case, it is 6%, or 6 people out of 100 will get bowel cancer in their lifetimes. What is the increased rate if you eat a lot of processed meat daily? 7%, or 7 people out of 100. So, if everyone ate processed meats only in moderation (about 50 grams is suggested, or two slices of bacon per day, or one bacon cheeseburger per week), we could avoid one additional case of bowel cancer for every 100 people who decreased their consumption.
That matters. That’s significant. But it also isn’t a one-to-one relationship. Processed meat does not “cause cancer” so much as it contributes to a slight increase in your risk of one type of cancer over your lifetime. And that isn’t even that much harder to say. Headline writers, please take note: your hyperbole is helping no one.