Diet sodas can lead to strokes! Zinc helps common colds! Pomegranate juice is an antioxidant powerhouse!
In a recent article in the San Francisco Chronicle, Marion Nestle explains why headlines like these can be misleading and how to question the studies that lead to them.
Nestle says that any study that makes a sweeping claim about a single food or ingredient sets off warning bells for her. She then mentions three major factors we should always consider when judging these health studies: plausibility, controls, and sponsorship.
Plausibility simply means asking yourself if the study makes sense. She points to the study linking diet sodas and increase heart disease, questioning their methods and saying, "Mostly, I can't think of a biological reason why diet sodas might lead to cardiovascular disease." If the study doesn't explain the link sufficiently, there's good reason to be skeptical.
By controls, Nestle means taking a look at how the study was carried out and whether the control groups were sufficiently, well, controlled. She mentions the studies done on zinc and Vitamin C supplements as an aid for the common cold with this one.
And finally, sponsorship of health studies is something for which we should always be alert. As Nestle says, "Vested interests influence the design and interpretation of studies." This is the case with the claim that pomegranate juice is high in antioxidants. Nestle explains that it's not so much that this claim is wrong, but that the study doesn't give enough context.
We really appreciate hearing how a nutrition and food policy expert like Marion Nestle approaches the headlines we read every day!
• Read the Article: Be Skeptical of Food Studies by Marion Nestle in the San Francisco Chronicle
Related: 2010 Dietary Guidelines: A Change for the Better
(Image: Flickr member lu_lu licensed under Creative Commons)
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This is great! Psuedo science is a menace y'all.
Industry-funded propaganda aside, I don't think the problem is with the studies themselves. If you take the time to look at the actual studies, they very rarely make sweeping claims. They suggest possible links, they not correlations.
The issue is really how the media report on those studies and how we as consumers try to find some clear-cut, hand and fast rule in them. The diet-soda/stroke study is a perfect example. If you look at what the scientists stated, they were very clear that they did not know why people who reported higher consumption of diet pop had more strokes, and specifically said the issue needed more study. But those caveats and qualifications were buried at the end of the stories about the study - when they were mentioned at all.
I'm with PilarJ, I find if you look at the actual study it may not be drawing the same conclusions that the media reports. The media likes a nice clear-cut sound bite and that is so rarely what science provides.
I'm with PilarJ, too. Although I think it's more that THE PEOPLE aren't interested in critically thinking about anything. Just the sound bites and the next dietary fixation, please.
I completely embrace Nestle's points, but reading study abstracts to understand the methodology is way beyond what the average person would ever do.
Likewise, it can take a fair amount of digging and backtracking to find out who is behind what in terms of sponsorship.
Sadly, it sort of goes without saying that the people who need this message the most are the least likely to pay attention to it.
Yeah, what PilarJ said. The problem is not with the studies, but how they are reported in the main stream media.
Also, most studies are funded by corporations. All that great research about chocolate being good for you? Funded by Nestle and Mars. Calcium good for weight loss? Dairy Council. Margarine being better for heart health than butter? National Association of Margarine Manufacturers. Cholesterol evil? Pharmaceutical companies.
Of course there are some privately funded studies, and the gov't funds a lot too. But, at the end of the day it's the corporations that have the cash to do studies that they have an interest in. It's just how it is. It doesn't mean the studies are bad or flawed per se.
Also, I hate Marion Nestle.