I love sugar! And who does not? Come on, who is the brave or the brave who raises his hand? (Not counting the exception that confirms the rule eh). We use the label “people addicted to candy” a lot to define those who have a hard time controlling the intake of sweet foods. In fact, just by putting in the search engine “Google” the words “addiction” and “sugar” we get more than 900,000 results. But is this assignment correct? Does sugar really generate addiction?
How do we regulate food intake?
Formerly (and I do not mean about 100 years ago, if not in primitive times), the search for food was solely for survival. On the contrary, at present it seems that food consumption is mostly driven by pleasure, rather than the need to obtain energy to survive.
However, in order to know better this drastic change in behavior towards food we will know a little about the physiological systems that regulate food. These are two systems that act in parallel and interact with each other:
- The homeostatic system
- The hedonistic or reward system.
The first system of regulation is hormonal, being regulated by leptin , ghrelin and insulin , which modulate hunger, satiety and adiposity levels. In summary, what this system does is stimulate or inhibit the action of feeding. Thus, if the energy balance of the diet is negative (under fasting conditions, for example), it stimulates the secretion of ghrelin and, this will lead to a stimulation of appetite . On the contrary, if the energy balance is positive, the synthesis of insulin and leptin is stimulated in order to balance the energy balance in the short and long term, respectively.
Turning to talk about the second system, the hedonist or reward, is the one that has the greatest impact on the issue of addiction. In fact, it is a way capable of annulling the homeostatic regulation system during periods of excess energy before very tasty and appetizing foods through the activation of the limbic system (part of the brain that regulates emotions, hunger, memory and instincts sexual). Therefore, food intake, although usually stimulated by a negative energy balance (homeostatic system), can also be stimulated by the activation of the limbic system through a pleasant sensation of a highly palatable food, causing an independent appetite stimulation to that caused by the first system in situations of fasting.
With all this, it is important to bear in mind that a dysfunction in the regulation of these systems implies a persistent positive energy balance state, with the consequent development of obesity.
Sugar as a synonym for addiction drug?
The search engine “Google” defines the term drug as follows: “Substance that is used with the intention of acting on the nervous system in order to enhance physical or intellectual development, to alter the mood or to experience new sensations , and whose repeated consumption can create dependence ”. So what does sugar do in our body to consider it as such?
The hypothesis that sugar can become addictive is based on brain reward mechanisms. When food intake is stimulated, it does not depend solely and exclusively on hunger, but also on other stimuli that we perceive through the sensory qualities of food. In the case of sugary foods, we do not find the anticipated perception that they are very tasty by providing us with an anticipated pleasure that activates regions of the limbic system, mainly due to the increase in dopamine secretion, which gives us pleasure.
Several studies have found several similarities that can lead us to think that sugar acts as a drug in our body:
- It has a high addictive potential due to the enormous secretion of dopamine that stimulates, which acts on the brain-stimulating a subsequent intake.
- Repeated intake of sugar can reduce the signalling of dopamine in the brain, so to achieve pleasure it will be necessary to consume a greater amount of food.
In addition, there are also studies that indicate that when the feeling of well-being invades us after eating pleasant substances, a memory is produced in the memory in which the reinforcing stimulus (in this case the sweet food) produces pleasure. This fact makes the brain interpret the food in question as beneficial, subsequently creating the same action to experience that pleasure again.
So, sugar as a synonym for addiction drug? Could be. However, there is a big difference that prevents this categorization of sugar, and this is that the motivation for drug use is only mediated by the hedonistic route, in contrast to that of sugar consumption, which is mediated by both systems as we have seen in this article: the homeostatic and hedonistic system.
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