Spinning Out Of Control

I don’t know about you, but I’ve never spent a lot of time contemplating the brain’s role in the development of obesity.  I, like I’m sure many others, have always thought about obesity somewhere along these lines: “Well, people like to eat, and they just have to control themselves… Some people are just more or less motivated to do this than others.”  Of course, this inner monologue usually had more context than I’ve introduced this with, and that context usually served to make the series of thoughts much more relevant and usually more serious.  I never stopped to consider that perhaps obesity, like many other things, is part of a vicious cycle, where one struggles to get off the train after he or she initially gets on.

There are two main types of neurons that are important in the regulation of appetite, and that subsequently appear to be quite important in the development of obesity.  POMC neurons, when activated, will essentially send the signal that you are full, and that you don’t need to eat any more.  One of the main molecules that is involved in sending this signal is called CART.  On the other side of things, ACMP neurons send the signal that you are hungry, and that you should eat.  This is done largely through the actions of neuropeptide Y, or NPY.  Maintaining the proper balance of activation of these neurons is very important in maintaining proper nutrition levels.  It is very interesting to note that when you eat and what you eat can alter the signaling in these neurons.  For instance, what is usually considered to be an unhealthy diet will deactivate the “don’t eat” POMC neurons and activate the “eat” ACMP neurons.  As a result, when one starts to eat unhealthily, it is perpetuated by a desire to continue to overeat.

To me, this starts to raise questions about the role of free will in obesity and other diseases of the brain.  We can become somewhat addicted to food in a similar manner as things we consider more to be “drugs,” and as we learn more and more about the many facets of addiction, we find that although free will is never completely absent, it may become harder and harder to summon as the hole which is dug gets deeper and deeper.  It is hard to think of obesity this way, as it is something that so many people suffer with, and oftentimes it is truly difficult to get back on the right path.  The problem is not helped by the fact that the cheapest food around is the most unhealthy.  If a family is struggling with money, eating salads may not necessarily be at the top of their priority list.  As a result, people may become trapped not only by the neurological basis of overeating or poor nutrition but also by the socio-economical trap of not being able to eat healthy foods on a regular basis, and thus the situation often quickly spirals out of control.