Soda Pop Cop

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Mayor Bloomberg made news last week with his proposed ban on sodas larger than 16 ounces. It has sparked quite a controversy. Even his daughter spoke out against the ban. This is his attempt to reduce obesity by controlling the behavior of those who consume too many calories. On the surface, this looks like a simple solution: turn down the ‘soft drink size knob’ and down goes obesity. There is no doubt that Mayor Bloomberg had good intentions with this proposed ban. But it raises some questions. Is such a move scientifically sound? Are there unintended consequences of this 'one size fits all' approach? Is this move respectful of the personal boundaries and decision-making of millions of human beings who are potentially affected by the ban?

SCIENCE AND COMPLEXITY

Our sweet tooth likely comes from evolutionary programming where throughout history sweet foods were a rare resource. According to the "multipoint attachment theory", the human sweetness receptor has 8 distinct regions.  This results in pretty complex interactions determining what is sweet.  Also, individual assessment of sweetness and desireability of various tastes obviously varies. If it didn't, we would all like the same foods.

Sugar has very deep evolutionary roots. Bacteria migrate towards sugar sources through a process called chemotaxis. Slime mold can actually navigate through a maze seeking out a food source.  Since antiquity, all organisms have been driven to seek out useable carbon sources. Perhaps there were more specific uses of sweetness targeting in humans. It may encourage us to seek out fruit, for example, helping us stave off scurvy.

There's no doubt that our desires for caloric intake have the potential to sway our decisions in unhealthy ways in today's society of highly abundant food sources. Human ingenuity has created a level of prosperity that requires a higher level of self-control.

Politicians often see themselves as problem solvers. As a scientist I can relate to the desire to look at many things in the world as a problem that I could solve. It's a sort of engineering mindset. In fact, if I look at problems in a strictly linear manner, it’s tempting to think that almost any problem can be solved with a teaspoon of science.

Real life problems aren’t so simple. Even in science, things are often too complex for a simple solution. We may find a great molecular target for a cancer therapy, but it may not work outside a plastic tissue culture flask. The entire system called a human being, with all it's organs, and intricate feedback loops presents problems with translating a proposed therapy into a real solution.

I would argue that while we have many selective facts about individual contributions to weight gain, we really don’t know that much about the causes and effects of various approaches on obesity as a complex system. Psychology is likely a major cause of complexity. There are many different diets out there and different diets seem to work better for different people. There are likely ethnic background effects, genetic predispositions, and individual food preference impacts. Some blame carbs, others blame fat, others say calories are all that matter. Mainstream beliefs push vegetables and fruits, while others say that throughout evolution we likely did not eat fruits daily. Then there are things like stresses in daily life which are very unique from person to person, but definitely impact behavior. If our understanding of ‘healthy eating’ is so concrete, why is there so much disagreement about the topic? Why do expert recommendations seem to be in a constant state of flux? Why did we need to change from four food groups to a pyramid and why does the pyramid conflict with the low carb perspective?

PERSONAL BOUNDARIES

What we do know is that at the individual level, psychology plays a major role. On an evolutionary scale, sweets were likely a scarce resource and this may be the reason many have strong desire for sweets. But even that seems to vary from individual to individual. There are so many complicated interactions. However, overconsumption of anything is a boundary problem.

Avoiding excessive calorie intake requires ‘self-control’, which is basically good boundary use. It’s the ability to say no to yourself. When it comes to self-control, many scientists believe that the Pre-frontal Cortex (PFC) plays a major role. Studies have shown that when people try to give up more than one habit at a time, they frequently fail at both. Some scientists believe that you run the risk of overwhelming your PFC when you use too much self-control. In other words, we have a limited amount of self-control available at any given time. This is why it is often adviseable to work on giving up one bad habit at a time.

Gaining control over a bad habit is sort of like hard-wiring yourself by applying self-control repeatedly, creating a good habit to replace the bad. At first, you use lots of energy fighting the temptation for the bad habit, but eventually the new way is your habit. This frees up the PFC to control other behaviors you are working on. Modifying someone’s soda uptake when they are trying to give up other possibly riskier habits can have unintended consequences. You may destroy someone’s attempt to give up smoking, for example.

While we are on the topic of boundaries, we may want to consider Mayor Bloomberg's boundaries. One key feature of good boundaries is knowing what is within your control and what is not. The obesity weight of the New York population is not likely within his control. Another key feature of good boundaries is being respectful of other people's boundaries. What size soda someone buys is within their control and to try to take control of that is stepping inside their personal boundary. This policy does that in a major way. Not only is he saying “You must lose weight.” He is saying “This is HOW you must lose weight.” A parent plays such a role with children, essentially patching their boundary holes as they develop their own. As an adult, someone trying to take over your boundary feels very intrusive.

UNINTENDED CONSEQUENCES

Unintended consequences are a natural result of complexity.  As mentioned earlier, one of the unintended consequences is disrupting individual efforts to control other behaviors like smoking. There are of course other types of unintended consequences. People may buy 2, 16 oz drinks because they can’t buy a 24 oz drink. They may spend more money or spill soda on themselves trying to carry two drinks. What about the common movie date practice of sharing a soda? Is it ok to take away that intimacy? What about the irritability that may follow? New York city could become filled with edgy people.  These are pretty simple consequences.  The whole myriad of effects that could be caused by things like the emotional aspects of psychology creates possibilities that I would not claim to be able to predict.

So if we ban soda, what should we try next?  Should we eliminate hot dog carts? Forced exercise?  Is fat unhealthy? Who decides? Why does the food chart keep changing? Personally, I don't agree with the food pyramid. If I were to ban something it would be rice and potatoes. While, many would agree with me, to some people that would interfere with THEIR diets. That's why I believe it is best left to the individual.

It would be nice if society would develop healthier attitudes. Attitudes are a psychological thing. Changing psychology requires effort at the level of the individual. You can't change psychology of a population by turning a knob.

Let me know what you think in the comment section below.