Disagreeing with Skeptoid
by Eric Hall
September 21, 2013
wrote a post about using Skeptoid as a reference and how that wasn't easy since pseudoscience supporters tend to dismiss any skeptical website. Today, I am going to take Skeptoid head on and point out what I think is a misapplication of logic and perhaps an oversight of the science on a particular topic.When I first started writing posts for the Skeptoid blog, I
In June, Brian produced an episode called "Legislating Pseudoscience." Certainly pseudoscience is something that gets legislated on a regular basis. One only has to start with searching the Dietary Supplement Health And Education Act of 1994 to understand how poorly many legislators understand science. Brian took on topics such as vaccines, GMOs, climate, and even someone trying to change pi to be something other than the ratio of a circle's circumference to its diameter. The topic on which I am going to disagree, although perhaps pedantically, is the New York ban on sugary drinks.
In 2012, New York City mayor Michael Bloomberg's health board passed a law banning all sugar-sweetened drinks larger than 16 ounces from being sold in restaurants (including fast-food), movie theaters, and other similar venues. The basis being that people eating or drinking "empty calories" is a large component of the obesity problem in the United States. While the ban has now been overturned in court, it was still pending at the time of the episode. Here's Brian's take on it:
The ban is gutless because only certain retail channels are affected, but it's bad science because virtually any restaurant meal contains far more calories than even the largest soft drink.What Brian did here was oversimplify the science. He is making an assumption that people consume equal quantities of these larger calorie sources. If I eat a 2000 calorie meal once a month, versus grabbing a 5o0-calorie soda daily in the local drive-thru, the soda will certainly have more of an effect on my weight. This is exactly what is happening. The newest study on sugary drink consumption from the American Journal of Preventive Medicine shows Americans over the age of 2 consume 8% of their daily calories from sugar-sweetened beverages. It is bad science and bad logic to conclude people will automatically replace those calories if the portions were limited.
There is also more interesting science on how people consume food. One I often cite is the "bottomless bowl" experiment. In this experiment, participants ate soup from bowls that were visually the same, but some of them were able to be refilled from the bottom slowly so the participants did not know the bowl was being refilled. Those with the refilling bowls ate a much higher quantity. The participants did not perceive eating more. From the abstract:
...despite consuming 73% more, they did not believe they had consumed more, nor did they perceive themselves as more sated than those eating from normal bowls. This was unaffected by BMI.I believe this would say that if given a smaller container, people will still feel just as satisfied while reducing their calorie intake.
The very size of the container can also make people misjudge the number of calories they are consuming. Cornell University did a series of "large plate" experiments showing that the size of the container affects both how much is consumed as well as the ability to estimate the number of calories consumed. In one dramatic example:
...in a study conducted at a health and fitness camp, campers who were given larger bowls served and consumed 16% more cereal than those given smaller bowls. Despite the fact that those campers were eating more, their estimates of their cereal consumption were 7% lower than the estimates of the group eating from the smaller bowls.The counter argument to those above might be something brought about as a part of the Affordable Care Act aka "Obamacare." Menus in restaurants and other places are now required to more clearly and prominently display the calorie content of the food and beverages. However, even with awareness, people will consume what is available. In an Australian study, participants took part in an educational exercise which talked about portion size and other factors that influence how much people eat. After the exercise, the participants were served lunch of two different proportion sizes. Those served the larger portion ate 30% more, despite just being informed of how portion size affects how much people eat.
Where I agree with Brian is the law was gutless in the fact its scope was limited and didn't address many other calorie sources. However, the genesis of the idea wasn't completely without plausibility when looking at the science. It also isn't necessarily bad science to try to make small gains against a larger problem. We sometimes tackle easier problems first because they can be done more quickly. I might be able to make a larger impact on the emission of carbon dioxide by buying a hybrid car, but until I can afford it, I will keep my oil changed and my tires properly inflated to make a smaller contribution to helping the problem.
As an aside, legislating science, even good science, is something that needs to be considered carefully. In the case of vaccines, there is a pretty clear concern beyond just the person being vaccinated, which is why stronger measures should be in place to both encourage vaccination and to make it more difficult for people to use non-medical exemptions. In what people choose to eat, there is not as clear of an answer as to where the line between public and private health concerns should be drawn. I am not a policy expert, but certainly more than just science needs to be considered when making policy. In the case of a ban on sodas, the science tells us it might have a small but meaningful effect. The science doesn't clear up the issue as to if it is the role of government to make that call.
by Eric Hall
@Skeptoid Media, a 501(c)(3) nonprofit