IARC Demonstrates Why Nutrition Science Is Terrible
A “landmark” study in the journal Annals of Internal Medicine discovered the fountain of youth tastes a lot like freshly brewed coffee.
After examining the diets of more than 500,000 Europeans over roughly 16 years, researchers found that increased coffee consumption was associated with a reduced risk of death from all causes. Cue the flood of headlines claiming “Coffee drinking could lead to longer life.”
If the constant flip-flopping of whether or not coffee is good for your health is giving you the jitters, you’re not alone.
In 1991, the International Agency for Research on Cancer (IARC) shamed baristas everywhere by first declaring coffee as a possible carcinogen. Then, after digging in its heels for over 25 years, the agency recently admitted that coffee doesn’t actually cause cancer. Oops?
Despite being a semi-autonomous arm of the World Health Organization, IARC is notoriously loose in issuing cancer classifications. The group claims everything from working the night shift to using a cell phone likely cause cancer in humans. Unfortunately, IARC frequently bases its decisions on studies that don’t quite capture the full picture of human health.
Take the agency’s recent tangle with red meat, for instance. In 2015, IARC concluded that red meat probably causes cancer in humans due to its weak association with colon cancer.
Yet studies show even after eating a burger-sized portion of red meat every day for a lifetime, the heaviest red meat consumers had less than a 2 percent increase in cancer likelihood. Even IARC’s own cancer database indicates that South America, home to four of the top ten meat-consuming nations, sees fewer cases of colon cancer than the global average.
Last month, Reuters further tarnished the agency’s credibility when an investigation uncovered that senior IARC scientist, Dr. Aaron Blair, may have deliberately withheld information from IARC’s review of glyphosate, the world’s leading weed killer. In a sworn deposition, Dr. Blair admitted that the agency likely would not have labeled glyphosate a probable human carcinogen if his missing data had been included.
Interestingly enough, the latest back-and-forth around coffee also comes from IARC. Four of the coffee study’s authors, including lead researcher Dr. Marc Gunter, are current IARC scientists.
Just like claims that someone’s lifelong medical history can be sidestepped with an extra morning brew or one less rib eye, the coffee evaluation should be taken with a grain of salt – or perhaps in this case, sugar.
Although researchers followed hundreds of thousands of participants for more than a decade, volunteers were only asked about coffee consumption once. Scientists can hardly claim a trend exists because of a single data point, especially since the amount of coffee people drink varies throughout their lives.
Gallup polling, for instance, indicates that consumption decreases from 3.8 cups a day to as low as 2.4 cups as the coffee drinker earns more. Yet despite drinking fewer cups, high earners typically live longer. Clearly, more factors are at play than the humble cup of Joe.
Despite not bothering to follow up on the single variable his study was supposed to evaluate, IARC’s Dr. Gunter proudly noted, “We found that higher coffee consumption was associated with a lower risk of death from any cause, and specifically for circulatory diseases, and digestive diseases.”
Similarly, if a participant only tried cigarettes once and didn’t die prematurely, this type of partial reporting would fail to capture the true dangers of smoking. Somehow, I doubt the media would be singing praises in such a scenario.
None of this is to imply that coffee is dangerous – in fact, quite the opposite is true. Even if the miracle bean turns out to be more Jack than Giant, the overwhelming body of evidence indicates that moderate coffee consumption won’t negatively impact one’s health.
But IARC’s poor research methods make it even more confusing for the average reader to pick science from pseudoscience. It’s no surprise that IARC is behind yet another poorly performed study – especially one upholding its newfound belief that a latte won’t actually make you drop dead from cancer.
Unfortunately for regular coffee drinkers – and those with a casual interest in their own health – nutrition science is regularly diluted by weak research and flashy headlines. The threat of science losing sway in the public eye is a serious concern in our time, which is why we must toss the sensationalism out with yesterday’s coffee. Fortunately, that advice isn’t rocket science.