If you live in the US, you’re probably aware of the problem we have with obesity. Even if you don’t live in the US you most likely have the perception that all Americans are fat, which isn’t completely false. America has nearly 40% of the world’s McDonalds, and over 11,000 more restaurants than the country with the
2nd most McDonalds. Eating badly is ingrained in our culture, and in some cases, is our culture.
With the existence of concepts such as fat shaming, some people believe that obese individuals can simply stop eating more than they have to. Now I don’t want to say that overeating isn’t a part of being overweight or being unhealthy, because it is, but are overweight individuals as in control as we think they are? Everyone has the choice of what they eat (assuming you have the income, although this isn’t a fair assumption either), but in a lot of ways, overweight people should not be fully blamed for the pounds they put on. Recent research shows that certain types of food, such as food that is high in fat, can be neurologically addictive. Because of this addictive quality, some are arguing for a place to be made in the Diagnostic and Statistical Manual (DSM V) for obesity as a mental disorder.
It has been found that there are a number of ways in which food, specifically food that is high in fat, can have addictive qualities. In some ways this assertion is already intuitive, as you never just want to have one donut. However, we can see the effects of this addictive quality on a deeper, more scientific level than simply being aware of its effects. For instance, deficits in dopamine transmission are induced within a high fat diet. Simplified, this means you don’t feel as good over time while eating the same amount of unhealthy food; the enjoyment diminishes on a neurological level. This in many ways parallels when a tolerance has been built up through repeated drug use.
It is commonly understood in research that obesity most likely causes increased inflammation, and inflammation may result in higher levels of obesity, though all the exact mechanisms for this loop aren’t known yet. What we do know is that obesity-related systemic inflammation reduces the integrity of brain structures involved in reward and feeding behaviors. To simplify this, this means that obesity triggers system-wide inflammation, which reduces the amount of control that we have over rewarding behaviors, including our food intake. Over time, our mental system of self-protection against resisting treats may be eroded by the fact that we’re eating these treats. A reduced integrity of reward systems has been found in 
drug addicts, where cortical brain regions involved in executive control and decision making have been heavily implicated. Through eating a high fat diet, we might be allowing our brains to think that eating more high fat items is what should occur.
One study looked at fibrinogen (a protein that’s found in blood) as a marker for inflammation, in which more fibrinogen means more inflammation. Unsurprisingly, fibrinogen was higher among obese individuals. An interesting finding however was that volumes of the orbitofrontal cortex in obese participants were negatively associated with fibrinogen levels. One of the functions of the orbitofrontal cortex is impulse control, and so damage to this area can lead to both impulsivity and compulsivity. Just because there is a difference in volume here however doesn’t mean it’s due to fibrinogen, so researchers controlled for variables within lean subjects, and found that 9% of the variance in OFC volume could be explained by fibrinogen. This, unfortunately, doesn’t bode well for obese individuals. In the case of obesity, we might be our own worst enemies, as we may be unintentionally sabotaging our own willpower by consuming a high-fat diet.
