A study published in the journal Food and Humanity (FH) revealed that a breakfast high in sugar and fats can significantly worsen well-being and mental activity in the first hours after eating.
As part of the experiment, young women were offered two types of breakfast on different days: a balanced one and a sweet one high in fats, with the calorie content being the same. The results demonstrated that participants more frequently experienced drowsiness and performed worse on planning tasks and switching between them after the sweet and fatty breakfast. These cognitive functions are related to concentration, learnability, and work efficiency. In contrast, the balanced breakfast contributed to increased alertness and a subjective feeling of energy shortly after eating.
Physiological data confirmed these findings: the sweet and fatty breakfast led to the dominance of the "rest mode" in the functioning of the nervous system. This refers to a decrease in heart rate and activation of the parasympathetic nervous system, which is typically active during rest. Such an effect may be beneficial in the evening; however, in the morning, it hinders active mental activity.
The authors of the study note that their work is time-limited; however, the results emphasize the importance of breakfast choice. Scientists believe that the habit of starting the morning with sweet pastries and fatty foods can subtly worsen mood, reduce concentration, and negatively impact work performance, especially in women.
