Michael Joyce is a writer-producer with HealthNewsReview.org and tweets as @mlmjoyce
It doesn’t help matters when a news release opens with a quote like this from one of the study’s lead authors:
Artificially sweetened drinks have a checkered reputation in the public because of the purported
health risks that have never really been documented. Our stu
dy clearly shows they help avoid cancer recurrence and death in patients who have been treated for advanced colon cancer, and that is an exciting finding.
Actually, it’s not that clear at all.
Mainly because this is an observational study suggesting that colon cancer patients who regularly drink diet soda have a lower risk of their tumors coming back, or of dying from their cancer. With this type of study it’s inaccurate and misleading to imply this is a cause-and-effect relationship.
Two other reasons make it not so clear:
First, the data on diet soda consumption are drawn from participants trying to accurately fill out food and drink questionnaires mont
hs after the fact. This sort of self-reporting has been shown to be highly unreliable.
Second, the study could not determine if other risk factors — such as diet, activity level, smoking, and other lifestyle choices — might contribute to lower cancer recurrence and mortality.
We were glad to see these limitations included in a HealthDay news story, but it’s not good journalistic practice to reprint quotes regarding the touted benefits directly from the Yale news release, which the story did.
It’s noteworthy that the quote featured above, from Charles Fuchs MD, MPH (Director, Yale Cancer Center) is at odds with more cautious language he used in the video embedded in the news release. He says: