Wednesday, October 13, 2004


Because it might offend the French!

A town has decided not to mark next year's 200th anniversary of the Battle of Trafalgar - because it might offend the French. Councillors in Totnes, Devon, feared that joining commemorations of Nelson's victory over the French and Spanish could upset their twin town in France. Totnes councillor Geoff Date said: "The town council decided not to support the Trafalgar celebrations. "I said I didn't think it was right to celebrate a defeat over the French when they have been our allies in the last two world wars. "We felt the place to remember that sort of thing was Remembrance Day." Other councillors were worried that marking the anniversary could offend people in Totnes's twin town of Vire in Normandy, he said.

A series of public events are being held around Britain to mark the bicentenary of the 1805 sea battle, in which Nelson was killed.



"Last week, a study led by Barry Popkin, PhD at the University of North Carolina at Chapel Hill, was released which claimed soda consumption had increased 135% since 1977 and since rates of type 2 diabetes and obesity were rising, too, that was evidence that "consuming these [drinks] increase weight gain in children and adults." Based on that correlation alone, they then leapt in reverse to conclude, "reduced soft drink and fruit drink intake ... would seem to be one of the simpler ways to reduce obesity in the United States."

Did you catch the fallacies in this example? Just because consumption of a certain food goes up or down among an entire population does not demonstrate that only fat people are eating that food or that that food is the cause of obesity or type 2 diabetes. Such correlation-generated claims rely on the belief that fat people eat differently. But consumption of sodas and sweets, for instance, have been shown to actually be as high or higher among thinner, more active people. Such claims also rely on the belief that sugary foods and beverages cause obesity and type 2 diabetes. But sugar has been studied probably more than any other food ingredient in history and it's been repeatedly found to not cause obesity, type 2 diabetes or any chronic disease. In fact, a surprising number of studies have demonstrated an inverse relationship between dietary sugars and obesity.

Popkin cited a study led by David Ludwig of Boston Children's Hospital in 2001 to support sweet beverages' role in obesity, which Popkin said "showed the effect of increased consumption of sugar-sweetened beverages on increased energy intake and obesity among U.S. teens." But Ludwig's study actually found no difference in the BMIs of children consuming the most and least amounts of sugar and the researchers noted "there is no clear evidence that consumption of sugar per se affects food intake in a unique manner or causes obesity."

The Popkin study was a "meta-analyses," lumping together five different dietary surveys (telephone surveys to questionnaires) gathered over the decades from a total of 73,345 random individuals. These one- and two-day population dietary surveys were all done using different methods and also underwent significant redesigns over the years to probe for more complete information and lessen under-reporting, meaning the earlier surveys would be more likely to under-estimate how much people actually ate and using them would accentuate perceived increases. Like all meta-analyses, when researchers combine data from several different sources trying to create something bigger and more convincing, their results are actually more untenable. I call them Rorschach studies. That might explain why sounder studies, such as those at the University of Michigan led by Youngme Park which closely following the diets for weeks at a time for years of a total of 12,000 children, have found no increase in soda consumption and no evidence that sodas were reducing milk consumption.

Of the thousands of foods and beverages people consume, this study chose sodas. But in typical data dredge fashion, Popkin could have mined that databank and pulled out anything...and has. For example, in a previous study he found grains, legumes and low-fat milk intake up among adults since 1965, along with significant decreases in calories and percentages of dietary fat. Yet he didn't tie these overall "healthful" eating trends to rising rates of obesity or type 2 diabetes. Why, that wouldn't have made sense!"

More here.

(For details of another "meta-analysis" in another field that was at least as disreputable, see here).

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