This newspaper report demonstrates how it’s possible for a reporter to do a competent job covering the news but fail to provide important information for readers.
The study, which demonstrates that caloric restriction may improve memory in older people, delivers the essential findings adequately, mentions some key caveats, includes comments from three experts and places these findings in the context of previous work done with animals and humans.
But the report fails to look beyond the narrow findings and answer important questions people will want to know as they [understandably] imagine how they might put these findings to practical use:
1. How much/little food did the restriction group eat? A 30 percent restriction for someone eating 2,000 calories per day is 1,400 calories; for someone eating 1,700 per day, that’s 1,190. Those are tough numbers. People would want to know that.
2. Is it clear the results were due to caloric restriction, not weight loss? This is the proverbial caveat big enough to drive a truck through, yet it was not mentioned.
3. Is it safe for older people–or anybody–to restrict calories by 30 percent?
The failure to take up that last question is particularly serious. Older people who are not overweight could wind up malnourished if they tried to restrict their calorie intake by 30 percent. Other news organizations mentioned this prominently in their stories. The Times should have too.
Cost is not a major issue in this story.
The story states that the caloric restriction group saw a 20 percent average improvement in memory performance. The report also describes the size of the group tested and the duration of the study.
It would have been useful to know how memory was tested in order to appreciate what a 20 percent improvement means in practical terms. 20% of what? 20% that makes what kind of difference in daily functioning? Maddeningly, the story does not report how many calories the restriction group ate on a given day.
The story mentions that some earlier studies found that caloric restriction was linked to memory decline.
But it fails to mention one very important practical warning relevant to the study populations: That older patients are at increased risk for malnutrition, and should not restrict their caloric intake without medical superivision.
Further, it’s not known whether caloric restriction is safe for slightly overweight or normal weight adults regardless of age.
The article properly describes the basic limitations of the evidence: that the study is small and the results less than conclusive.
But the report fails to mention two important caveats:
That caloric intake was based on participants’ self-reports, a notoriously undependable way to determine diet compliance.
That the data don’t rule out whether the improved memory may be linked to weight loss rather than caloric restriction.
Finally, there’s one intriguing potential explanation that might have been explored: whether the cognitive improvements might be related to performing a new mental task daily for three months: Counting calories and logging food intake.
On balance, the story receives an unsatisfactory rating under this criterion.
The story does not exaggerate the severity or incidence of memory loss in older adults.
The reporter interviewed one of the study researchers, a lead researcher in a related study and one independent expert.
Other tactics have been shown to boost older adults’ memories, including aerobic exercise and some social and behavioral activities. But in this story, which focuses on a key finding about dietary restriction, it is not necessary to mention these options.
The availability of caloric restriction is not in question.
The story does a good job of briefly sketching out the history of caloric restriction testing in animals and people, making clear that caloric restriction is not novel.
The story turned to several sources and did not appear to rely solely or largely on a news release.