There is this link, often observed in real life, between hunger and bad mood. Researchers at the University of Guelph (Ontario) demonstrate this here in mice and in the journal Psychopharmacology. Their work shows how the sudden drop in glucose, associated with the feeling of hunger, can affect our mood.
In English, the concept of "hangry", a mix of "hungry" (starved) and "angry" (in a bad mood) stands, on reading these new data: "We provide evidence that a change in glucose levels can have a lasting effect on mood,” summarizes the lead author, Professor Francesco Leri, from the Department of Psychology. "I used to be skeptical when people told me they got grumpy if they didn't eat, now I believe it."
Hypoglycemia is a physiological and psychological stress:the team looked at the impact of a sudden drop in glucose on emotional behavior by inducing hypoglycemia in rats. The rats were injected with a glucose metabolism blocker, which induced hypoglycemia, and then placed in a specific chamber. In a “control” phase, they received an injection of water and were placed in another room. When the rats were given a choice of room, they actively avoided the room where they had experienced hypoglycemia. This type of avoidance behavior illustrates stress and anxiety here: the animals avoid this room because they have had a stressful experience there and do not want to experience it again. Moreover, when researchers analyze blood samples after hypoglycemia, they do note an increase in corticosterone, an indicator of physiological stress. Finally, the rats move more slowly after the injection of glucose metabolism blocker. And it's not because they lack the energy to make their muscles work, because on antidepressants and despite this hypoglycemia, the animals move normally.
These different observations support the theory that the animals experienced stress and depressed mood when they were hypoglycaemic.
What are the implications for humans? For people with anxiety or depression, these findings have treatment implications. Knowing that nutrition is a factor, we can include dietary habits in the overall management of the patient. Second, these results also document the link between depression and diseases such as obesity, diabetes, bulimia and anorexia. Finally, since hypoglycemia contributes to these negative mood states, it will be necessary to determine whether chronic hypoglycemia is a risk factor for depression.
" Bad mood and poor diet can become a vicious circle: if a person doesn't eat properly, they may experience a low mood, and that low mood can prevent them from eating ."
Finally, when we think of bad mood and stress, we think of possible psychological factors but not always of metabolic factors…