Here’s the conclusions from a longitudinal study of diet, exercise and weight gain:
Within each 4-year period, participants gained an average of 3.35 lb (5th to 95th percentile, −4.1 to 12.4). On the basis of increased daily servings of individual dietary components, 4-year weight change was most strongly associated with the intake of potato chips (1.69 lb), potatoes (1.28 lb), sugar-sweetened beverages (1.00 lb), unprocessed red meats (0.95 lb), and processed meats (0.93 lb) and was inversely associated with the intake of vegetables (−0.22 lb), whole grains (−0.37 lb), fruits (−0.49 lb), nuts (−0.57 lb), and yogurt (−0.82 lb) (P≤0.005 for each comparison).
Aggregate dietary changes were associated with substantial differences in weight change (3.93 lb across quintiles of dietary change). Other lifestyle factors were also independently associated with weight change (P8 hours of sleep), and television watching (0.31 lb per hour per day).
And here’s the New York Times article summarizing the findings:
People don’t become overweight overnight.
Rather, the pounds creep up slowly, often unnoticed, until one day nothing in the closet fits the way it used to.
[…] The beauty of the new study is its ability to show, based on real-life experience, how small changes in eating, exercise and other habits can result in large changes in body weight over the years.
On average, study participants gained a pound a year, which added up to 20 pounds in 20 years. Some gained much more, about four pounds a year, while a few managed to stay the same or even lose weight.
[…] The foods that contributed to the greatest weight gain were not surprising. French fries led the list: Increased consumption of this food alone was linked to an average weight gain of 3.4 pounds in each four-year period. Other important contributors were potato chips (1.7 pounds), sugar-sweetened drinks (1 pound), red meats and processed meats (0.95 and 0.93 pound, respectively), other forms of potatoes (0.57 pound), sweets and desserts (0.41 pound), refined grains (0.39 pound), other fried foods (0.32 pound), 100-percent fruit juice (0.31 pound) and butter (0.3 pound).
There are a lot of limitations to this study. First, the population being studied appears to be entirely made up of ‘nurses, doctors, dentists and veterinarians.’ This is hardly representative of the public at large, and indeed the findings would seem less monumental if they were phrased as ‘nurses, doctors, dentists and veterinarians lose weight when they eat more yogurt.’
It’s also based solely on self-reported data. I can barely remember what I had for lunch yesterday, much less how much of it I ate or whether it was whole-grain. There’s at least some reconstruction going on in the answers to the questionnaires on which these findings are based
Third–and this is the problem with basically all research on health and diet–it’s purely correlational. This study gives no evidence that eating yogurt will make you lose weight, or that watching more TV will make you gain weight. The findings simply suggest that people who lose weight eat a lot of yogurt.
None of these gripes is a deal-breaker, and I’m sure the researchers are well aware of the limitations of their research. What’s interesting is that the New York Times article didn’t mention any of these limitations, and doesn’t give a clear accounting of the conclusions we can and can’t draw from this research.
Savviness is what journalists admire in others. Savvy is what they themselves dearly wish to be. (And to be unsavvy is far worse than being wrong.) Savviness—that quality of being shrewd, practical, well-informed, perceptive, ironic, “with it,” and unsentimental in all things political—is, in a sense, their professional religion. They make a cult of it.
Rosen’s talking about political journalism, but I think one of the wider consequences of this ‘church of the savvy’ bias is that it creates an opposition between journalists and their sources that doesn’t serve the interests of either.
Scientists are always complaining about how the press condenses and distorts their findings. This New York Times article, while it doesn’t do anything egregious, definitely slants the results toward ‘eat more yogurt!’ and ‘watch less TV!’, neither of which can be concluded by the research itself.
It strikes me that if either journalists or scientists were viewing this problem without any bias toward existing media structures, the solution would be simple: Write the article together.
Other than a perceived lack of savviness, what exactly is the problem with a journalist collaborating with her sources to produce an article summarizing their findings?
The journalist and the scientist share the byline. He contributes information on the study’s aims and methods, she frames the findings for a mass audience. She writes a draft, he corrects the areas where her conclusions aren’t supported by his research. They go back and forth until they have a draft that they both agree informs the public to the best of their combined abilities.
I know journalists find the idea of writing a story in collaboration with a source to be repellent, but in this case the scientist and the journalist share the objective of informing the public on a scientific phenomenon that affects their lives. This is the animating idea behind the wildly successful Freakonomics books: Snappy reporter teams up with maverick professor. One produces research, the other writes it up. This idea also produced The Wire: Ed Burns was David Simon’s source before he was his writing partner.
Given the importance of technical expertise in current-affairs debates such as sustainable energy, health and technology, the burden is on journalists to tell us why they don’t want to give up some of their savviness for a little more truth.