The story didn’t include even a word about the limitations of the study, and it didn’t challenge many questionable claims about the benefits of DHA made by an expert source.
When a story quotes an expert whose recommendations differ from those of major medical organizations, it owes readers an explanation as to why they should follow the advice. But in this story, an expert recommends that everyone get 1000 mg of DHA a day — which is far more than you would receive by following American Heart Association recommendations to eat two fish meals a week. And the only support the story offers are vague statements about how DHA “increases blood flow in the brain, reduces inflammation in the brain, heart and elsewhere, and reduces the toxic aggregation of amyloid in the brain.” Readers deserve better.
This story is about blood levels and surrogate markers of dementia (early changes in cognitive tests and MRI changes), not the ultimate health outcome of interest – dementia. The story should have pointed out the difference between supplements and dietary sources. We don’t know much definitively about supplements, but we do know more from observational studies of fish consumption.
The recommendations quoted in this story — get 1000 mg/d of DHA — are only achievable by taking supplements, so the story should have included a comment about how much these cost.
The story includes many sketchy statements about DHA, citing benefits for “improving mood” and “reducing symptoms of depression.” The story made these as flat statements of fact, but this is far from established science.
It also failed to provide quantified benefits from the study in question. Where are the absolute risk reduction figures?
“They found people in the bottom 25% scored lower on such mental tests as problem solving, multi-tasking and abstract thinking…..The MRIs showed higher white matter hyperintensity volume, tiny lesions in the brain, raising the risk for death, stroke and dementia for the low omega-3 fatty acids group.”
The story does mention that DHA has the potential to cause problems in people taking blood-thinning medication.
There was no discussion of any possible limitations to this research. A basic discussion of the limitations of observational study data would have been useful. Not sure how to do that? Read this.
There was no outright disease mongering, but the headline’s suggestion that your brain may “suffer” without sufficient DHA comes close.
The story did consult an independent expert. However, this expert’s recommendations opened the door to a lot of questionable statements about the benefits of DHA. So this is a rare case where the story probably would have been better without this outside perspective.
The story mentions alternative sources of omega-3 fatty acids and recommends the MyPlate government dietary guide. Other alternatives for dementia prevention such as exercise and mental stimulation could have been mentioned as well.
The availability of fish and fish oil supplements is not in question.
The story did not reference previous research suggesting a link between fish and cognitive function during aging.
We’ll flag the story here for pulling a quote directly from an American Academy of Neurology press release without stating that was the case. Here is the quote in question, which is attributed to a researcher with the study: “People with lower levels of omega-3 fatty acids had lower brain volumes that were equivalent to about two years of brain aging.” The story does make it sound as though the reporter talked directly to the researcher, so it’s not clear exactly what happened. But it’s fishy.