☕ Why your morning coffee has more effect than at any other time of the day?

A simple morning coffee is more than just a ritual. Behind this daily habit lie measurable effects on mood and perceived energy.

Researchers wanted to understand whether caffeine truly affects emotional state in everyday life, beyond laboratory experiments. Their work, conducted in Germany and the United Kingdom, sheds light on precise results regarding when its effect is most pronounced.

When caffeine acts most strongly

Scientists observed that positive emotions increased after caffeine consumption, especially within two and a half hours after waking. The effect remains perceptible but less intense later in the day.

A second, weaker peak appeared between ten and twelve hours after waking, possibly reflecting an interaction with biological rhythms. The emotions involved range mainly from enthusiasm to a more general feeling of happiness.

In contrast, caffeine does little to reduce negative emotions. A decrease in sadness or annoyance is observed, but it remains variable from person to person and does not depend on the time of day.

These results come from daily monitoring of several hundred young adults in Germany, who were invited to respond up to seven times a day to short surveys on their smartphones. This method made it possible to measure the effect of coffee in real life, outside the artificial setting of a laboratory.

Effects independent of personal profile

Researchers analyzed whether factors such as anxiety, sleep quality, or consumption habits altered this link. No notable effect was found. The results remain stable across different groups.

Caffeine dependence also did not change the overall trend. Morning coffee therefore provides a comparable positive effect, whether for an occasional or regular drinker.

Only situational factors, such as the degree of fatigue felt at the time of drinking or whether one is alone or accompanied, slightly modify the intensity of the emotional benefit.

To go further: how does caffeine work in the brain?

The positive effect of coffee on mood is explained by its action on a key molecule: adenosine. This substance accumulates in the brain throughout the day and promotes drowsiness. The higher its level, the more fatigue and the desire to sleep appear.

Caffeine works by blocking adenosine receptors. In other words, it prevents this molecule from transmitting its rest signal. The brain then interprets that it does not yet (or no longer) need to slow down, which maintains wakefulness and alertness.

Simultaneously, this blockage influences other chemical systems, particularly those of dopamine and norepinephrine. These substances are associated with motivation, attention, and feelings of well-being, which explains the increase in enthusiasm and good mood observed after a cup of coffee.

The results of this study are reminiscent of other research we have previously shared:
- Coffee may extend your lifespan... if you consume it at the right time ☕
- Here's how much caffeine you shouldn't exceed for your heart health
- Caffeine could help fight Alzheimer's
- Caffeine could reduce the risk of developing Parkinson's disease