The score may not show it, but this WSJ report was the weakest of the three competing stories on the same study. CNN and WebMD had far better analysis. While all three got four stars, there were important content differences among the three. Read the reviews to see what they were.
This story went into pretty fine detail on the best food sources of lycopene, an effort that would have been better directed toward critical evaluation of the study methods and findings. Although it did manage to provide readers with the absolute risks seen in the high and low-lycopene groups in this study (something the two competing stories failed to address), this story didn’t mention any of the caveats or limitations that we think should be communicated when reporting on observational studies. It never gets beyond a simplistic message — “tomato helps cut stroke risk” — that you’d expect from a product press release.
For years we’ve been hearing about the benefits of this or that “superfood” with the most antioxidants. But the reality is that there’s no strong evidence to support the health benefits of any particular fruit or vegetable over any other. All fruits and vegetables contain antioxidants and other nutrients that are important for health, and it’s the combination of fruits and vegetables in a healthy diet that seems to offer the most benefit for preventing chronic diseases. Anyone who says otherwise is probably either: a) trying to get a study published, or b) trying to sell you something, or c) both.
The emphasis of this story on lycopene content in foods seems to indicate that we should all get as much as we possibly can, and is misleading.
The cost of tomatoes, or other sources of lycopene, is not in question.
The story said that the risk of strokes was reduced by 55% in men with the highest lycopene levels, a relative comparison. But it also gives readers a look at what the absolute risks looked like: “There were 25 strokes among 258 men who were considered to have the lowest levels of lycopene while there were 11 strokes among men with the highest lycopene levels.” It was the only one of the three stories we reviewed that included the absolute risk figures.
We’ll rate this not applicable as we did for the competing stories, but with the caveat: Lycopene supplements haven’t been well studied and might cause adverse effects.
This story had the same inappropriate use of active verbs seen in the competing CNN and WebMD coverage: “Tomato helps cut risk,” “Tomatoes could lower the chance of having a stroke,” etc. This is a report from an observational study, and that needs emphasis. Please read our primer on association versus causation and why the language matters.
The competition redeemed themselves with an exploration of study limitations and the inclusion of cautious expert perspectives. But this WSJ piece largely accepts the results at face value. Most of the effort here seems to have gone into investigating the lycopene content of various foods, which reinforces the notion that lycopene is somehow the magic ingredient responsible for these findings. As the competing CNN coverage points out, there’s really no strong basis to conclude that lycopene or any other individual nutrient has strong benefits for stroke prevention.
The story does include a comment from an independent expert, who emphasizes that diet and lifestyle factors are important for stroke prevention. However, there was nowhere near the depth of context provided by expert sources in the competing coverage by CNN and WebMD.
And if the expert quoted in this story really said that lycopene “prevents blood clots from forming,” as the story suggests, then he is misinformed. There is no evidence that we’re aware of that shows lycopene prevents blood clots.
Diet, exercise, and not smoking are all mentioned as important factors for stroke prevention.
The availability of tomatoes is not in question.
There was no mention of how this research fits with previous studies on diet and stroke prevention. Also no mention about prior studies of antioxidant research on lycopene.
There’s no evidence that this story relied on a press release.