Best story out of the three reviewed on berries and heart attacks. NPR quotes an independent expert who talks about the study’s limitations – something that the HealthDay and TIME stories failed to do.
Even though it was better than the two competitors we also reviewed, the NPR story could have clarified a few points in its online version.
For example, although anthocyanin seems to be the likely component in reducing the risk for heart attacks, researchers are not completely sure, since the amount of anthocyanin cannot be measured. Researchers acknowledge that this protective effect may be due to another compound.
Also, the story doesn’t discuss harms, alternatives and costs – some of which may be understandable but not all of it. However, it does an excellent job in providing context for the study, quoting an independent source, and explaining that this study pointed to a statistical association, not cause-and-effect (although it could have stated the latter more clearly).
Reporting food stories can be difficult, especially when results are not crystal clear. But NPR, to its credit, does seem to have a more balanced view of the study than the other two articles, instead of just touting the benefits of berries. The public is understandably suspicious of more news hyping supplements or specific food components, only to find later that the results were inconclusive.
Not applicable. Costs not mentioned but we think most people know the ballpark cost of berries.
We understand that there is a time limit on radio stories. But on the online version, the story could have been expanded in order to clear up a few points.
The piece mentions that “red-, blue-colored fruits and vegetables can reduce the risk of a heart attack by about 32 percent in young and middle-aged women [ages mid-40s to 60].” Again, this is the figure associated with anthocyanin, after adjustment of multiple variables. The limited understanding of anthocyanin and its levels in the body introduces an important limitation in the study. Other factors may have been involved, which is something the researchers acknowledge in their journal article.
Regarding “benefit” – which cannot be proven in such an observational study – the reporter was careful to use terms like “hint of effects”…”linked to”…”suggests”…”relationship between berry consumption and heart disease.”
The key quote was: ” It’s certainly not a perfect way to detect how certain foods may influence health, but it identifies important associations”. It seems that the writer understood and tried to convey that interpreting cohort analyses is about association and not causation.
Like both the HealthDay and TIME articles, the NPR story did not discuss potential harms. But all health interventions have harms, as well as benefits and costs. We looked the other way on costs but not on harms.
We will give this story the benefit of the doubt, since it was the only story out of the three reviewed to mention any kind of study limitation. Cardiologist Dr. Robert Eckel points out, “Having a heart attack when you’re a woman between ages of 45 and 60 is distinctly unusual.” And he says that the benefits for older women are not as clear. NPR does an excellent job in bringing this up.
There is no sure way to measure the amount of anthocyanin in the body, so any possible effect could have been due to another variable. Furthermore, even though researchers tried to account for multiple factors in their analysis, it is impossible to account for all of them. They acknowledge in their study: “…it is impossible to disentangle the relative influence of all the constituents of fruits and vegetables.”
Again the key quote was: ” It’s certainly not a perfect way to detect how certain foods may influence health, but it identifies important associations”. It seems that the writer understood and tried to convey that interpreting cohort analyses is about association and not causation.
It could have more clearly explained that such studies cannot prove cause-and-effect. Interestingly, some of the online commenters even hit on this point, one writing:
“Correlation isn’t causation…The way the media reports these correlations isn’t always a good thing….Finding a large correlation like this is certainly a clue and a big red arrow pointing to a possible cause that should be studied further, but it isn’t the same as finding the cause. And taking action based solely on a correlation can often cause more problems than it solves.”
That’s a smart comment.
There is no disease mongering.
Cardiologist Dr. Robert Eckel is the independent source in the study who talks about a major study limitation. His comments are extremely helpful and bring more perspective to the study.
No alternatives are mentioned. To prevent heart attacks, patients can either take medications, such as blood-thinning and cholesterol-lowering drugs, or make lifestyle changes, like maintaining a healthy weight, exercising and not smoking.
The availability of strawberries and blueberries is not in question. But it does remind readers that if berries are not in season, frozen berries are still available and may have the same effect (if there is an effect).
The story does mention some previous studies on anthocyanin, looking at possible effects on blood pressure and anti-inflammatory response. NPR even goes into the history and previous research on blueberries, which has been linked to better brain health and decreased risk for Type II diabetes. Also, Dr. Eckel states, “…for the first time I think we have some evidence that the intake of theses anthocyanins may have a protective effect.”
The NPR story does not seem to rely solely on a press release, and there is evidence of original reporting with the independent comment from cardiologist Dr. Robert Eckel.