Fish, Brain Health and Alzheimer’s

Apparently, eating fish may be good for brain health.

I was the second reviewer for two HNR reviews looking at a recent study presented Wednesday at the Radiological Society of North America in Chicago. Researchers looked at the correlation between 3-D MRIs and gray matter in the brain. Here are two competing reports from HealthDay and WebMD :

Another confusing story about an observational study that fails to explicitly state and explain to readers the limitations of observational studies. Please read our primer on this topic.  It would help prevent these mistakes.

Our Review Summary

Readers heads must be spinning worse than Linda Blair’s in “The Exorcist” when they read – in one story – that this “must be viewed as an association, rather than a cause-and-effect” – yet they get cause-and-effect language such as:

  • “Raji said he was ‘amazed’ that this effect was seen”
  • “may boost brain health”…”lower the risk”…”helps to preserve gray matter neurons, strengthening them”…”cranial benefit”

Why This Matters

Over and over again, many news stories confuse readers about observational studies.  It leads to a loss of confidence in science and a loss of credibility in journalism.  That’s why this matters. []


Slightly better story than the competing HealthDay story on the same study. Still weak on explaining the limitations of observational studies.

Our Review Summary

The story allows the researcher to say, “More fish, more brain, less Alzheimer’s.”   Pithy.  Quotable.  But simplistic and not proven by this study.

Why This Matters

At least the competing HealthDay story interviewed an independent source who wondered about other possible confounding factors in the research and stated, “For now, the connection must be viewed as an association, rather than a cause-and-effect.”

So even though the WebMD story scored better, the HealthDay story did slightly better on this critical piece of analysis. (The HealthDay story had its own flaws – for example, burying that “association” line instead of placing it high in the story and overwhelming it with cause-and-effect language throughout the story.) []

You can see the full reviews on my site at Journalism -> Review and also at