Scientists have found: sugar provides energy but does not relieve stress

Scientists from the University of Konstanz have discovered that even when you are relaxing during a massage or simply resting, a sugary drink consumed beforehand prevents your body from truly "unwinding." Sugar silently activates the body's stress system, negating the effect of rest. The results of the study have been published in the journal Nutrients.

The experiment involved 94 healthy adult volunteers. Some of them abstained from food before visiting the laboratory, after which one group was offered a glucose drink and the other plain water. Then half of the participants received a relaxing massage, while the rest simply rested quietly.

Throughout the entire experiment, the researchers continuously recorded cardiac activity indicators — heart rate variability and pre-ejection periods, which reflect the balance between the parasympathetic and sympathetic nervous systems.

The data obtained demonstrated that both massage and simple rest successfully activated the parasympathetic system, responsible for relaxation — regardless of whether the person had consumed sugar.

"However, after glucose intake, the sympathetic system was simultaneously activated — the very system that maintains the body's heightened readiness and stress response. This means that although a person may subjectively feel calm, their body remains in a state of heightened arousal," the authors of the study clarified.

According to the scientists, sugar helps briefly mobilize energy to cope with stressful situations but simultaneously undermines the body's ability to fully recover. Regular and frequent consumption of sugary products, the specialists warn, can increase the risk of developing hypertension, obesity, and cardiovascular diseases.