I would like to share a word or two about food addiction, why it’s so horrible, and why it, along with extreme amounts of sugar, could be the key player when it comes to obesity.
A wonderful review examined the work of Dr. Hoebel. He was one of the first people who thought that sugar intake, or consumption of other foods that are extremely pleasing to the eyes, could have the same effects on our brain chemistry as drugs.
Let’s start with drug addiction
When talking about drug addiction, there are three common stages that should be familiar to people who are, or have been, addicted to any type of drug:
- The stage when you take the drug repeatedly in order to achieve its desired effects
- The withdrawal phase accompanied by negative emotional properties when the mentioned effects start to wear off
- A state of anticipation and preoccupation before the drug is taken again
This is a vicious cycle in which addicts will find themselves in. And this does not hold true only for the prototypical drugs you are probably imagining right now, this happens when talking about gambling, food, or any other substance or thing we do in our life that lures us into this cycle.
It starts with eating certain kinds of food to gain a “high” from it, you feel pleasure when experiencing the taste, the smell, the feel of it, and so on. Ths happens due to the brain’s neurotransmitters that get released (dopamine) when awaiting these foods. Imagine chocolate, different sweets, and similar foods that are high in fat and/or carbs.
Later on, however, this will get switched. You start eating the mentioned foods because you want to prevent the second phase from happening. As the treshold for achieving the same dopamine spike gets higher after a while due to neuroadaptation, you are forced to eat more of it at the same time.
Now you start eating these foods, which are often unhealthy, purely for the reason of preventing negative symptoms that would occur otherwise. These include anxiety, depressive symptoms, irritability, and different withdrawal symptoms that are often found in different drug withdrawals.
On that note, scientists developed a questionnaire to test whether people, who would consider themselves food addicts, would show the previously mentioned symptoms. In short, the results have shown that if you suffer from binges, there is a good possibility that you are addicted to the different types of foods which you’re eating during these bouts. This same result was found for emotional eaters as well . But keep in mind that I said ‘possibility’, not certainty. There is just a higher probability that you are addicted to such food. And I’m talking about in terms of actual addiction here, these are the same brain mechanisms that make cocaine addictive. And that’s not something to be taken lightly, is it?
But being a binge eater has multiple implications by itself. Besides the possible mentioned addiction to food, binge eaters are also more prone to having major depression, bipolar disorder, anxiety disorders, as well as being alcohol abusers   . This has a wide array of different ways how it can affect one’s health. Making it ridiculously harder to achieve a certain goal in terms of weight loss or just healthier eating.
Food and mood
First and foremost – depression and anxiety have different effects on people in general.
If you are a normal or underweight, chances are that you will eat less food when you are experiencing unpleasant emotional states. Overweight people, however, usually report to eat more during such unpleasant states. 
Therefore, researchers have been intrigued by the idea of inducing negative mood states in actual experiments, and then observing the dfferences in behavior which would occur in people. Before I continue – inducing different mood states in a laboratory/experimental setting is not very methodologically valid. People have a tendency to behave differently in a situation that is not structured beforehand.
However, the studies that were carried out, have so far supported the notion that the second phase of addiction; eating to prevent the feelings of sadness, is one of the possible triggers for overeating. The researchers have consistently found across multiple studies that people ate more food during studies where an unpleasant emotional state was induced. Be it sadness or just stress.    
The worst thing of all, emotional eating doesn’t really cure these emotional states, people are more relaxed, less tense, and calmer only for a few hours. 
As I’ve mentioned, some people did behave differently. This mostly depended whether they had high self control, as these people were less likely to eat in the laboratory setting. The question obviously poses, how would such people behave if they were at home?
The dark side of food addiction
I’ve already mentioned how the brain adapts to an increase in the availability of a certain drug, which in return makes you prone to this cycle, and especially the second phase of drug addiction. This is the dark side of it, you start eating certain foods in order to avoid feelings of sadness, anger, irritability etc. And this isn’t only true for food. After a full blown addiction, smokers need to smoke in order to avoid or reduce tension and feeling irritated. A common misconception is that cigarettes make you more relaxed and less irritated. However, the truth is that smokers actually become more tense and irritated than regular people when they are not smoking, and smoking a cigarette reduces this back to a “normal” level. The side effects of irritation and tension are just withdrawal symptoms of not receiving a cigarrete which become reduced when one smokes again.
But to return to food, besides the fact that your brain adapts to certain types of foods, there is a higher chance that you will want to eat bread, pasta, sweets, and other foods high in carbs/high in sugar/high in fat, because they are what your brain craves in these situations . In a reverse study, where people were switched from a diet that had a 40% caloric composition of fats to one that had a 25% composition of fats, they described themselves as angrier and more hostile in the month that followed the change. The group that didn’t change and stuck with the same eating pattern showed no difference on anger or hostility. 
And to finish off. What do you think will happen once your brain becomes adapted to a certain amount of unhealthy food? You have to progressively increase the amounts to find pleasure in it again due to neuroadaptation that I’ve mentioned before.
To explain this a bit further.
Hoebel and his colleagues saw incredible increases in the amount of glucose that was being consumed over few successive days when they tested this on rats. The amounts were rather consistent in the sense of developing a tolerance and a shift toward binge-like eating. The rats were basically increasing the amount of glucose that they were eating with every day that passed. Their brain adapted to a certain amount, after which they had to increase it. 
And to top all that off – another study that had quite notorious results, showed that rats preferred processed sugar over cocaine after some time. 
Food addiction is a serious issue, read the whole article.