Coffee is an integral part of the daily lives of millions of people around the world. For many, a morning cup is not just a ritual, but a way to stimulate the mind and improve concentration. But how does coffee actually affect our cognitive abilities? Is this improved focus a scientific fact or a placebo effect? ​​Let's take a closer look at how caffeine—coffee's main active ingredient—affects concentration and brain function.

Caffeine – how does it affect the brain?

Caffeine is a natural stimulant of the nervous system, belonging to a group of compounds called methylxanthines. Its main mechanism of action is blocking adenosine receptors in the brain. Adenosine is a neurotransmitter responsible for feelings of fatigue—its levels rise throughout the day, signaling the body that it's time to rest. When caffeine blocks these receptors, the brain doesn't receive the signal of fatigue, resulting in increased alertness and a greater sense of energy.

Blocking adenosine also leads to increased levels of other neurotransmitters, such as dopamine and norepinephrine. These chemicals are responsible for arousal, mood improvement, and increased concentration and reaction time.

Improving concentration and alertness – when and how?

Many studies confirm that caffeine in moderate doses can improve concentration, attention, and reaction time, especially when tired or sleep-deprived. The greatest effect is typically observed 30 to 60 minutes after consuming coffee, when caffeine levels in the blood reach their peak. The effect lasts for 3 to 5 hours, although it may last longer in some people.

Coffee has a particularly beneficial effect on executive functions, the mental abilities that allow us to plan, solve problems, and focus on a single task. Therefore, coffee can be invaluable for mental work, studying, or long car journeys.

Individual reaction to caffeine

It's worth noting, however, that caffeine's effect on concentration isn't the same for everyone. Genetics, body weight, caffeine tolerance, and lifestyle all play a significant role. People who regularly drink large amounts of coffee may experience a weakening of its stimulating effect—the body develops a tolerance, and caffeine doses become less effective.

In more sensitive individuals, too much caffeine can cause anxiety, irritability, and even impaired concentration. Therefore, it's important to monitor your own reactions and adjust your coffee intake to your individual needs.

How much coffee is the optimal dose?

According to the European Food Safety Authority (EFSA) , a safe daily dose of caffeine for an adult is 400 mg—the equivalent of about 3–5 cups of coffee. Just 75 mg of caffeine (about one small coffee ) can have a positive effect on concentration and attention.

However, just as important as the quantity is the proper distribution of coffee consumption throughout the day. The best results are achieved by drinking coffee at times when alertness levels naturally decline—for example, in the early afternoon. Drinking coffee late in the evening can disrupt circadian rhythms and impair sleep quality, which in the long term negatively impacts concentration and mental health.

Coffee, multitasking and creative work

Contrary to popular belief, caffeine doesn't always improve all aspects of mental performance. While it's excellent for tasks requiring attention and precision, it can somewhat limit creativity or flexible thinking. Therefore, coffee supports analytical work better than, for example, brainstorming.

Some studies also suggest that coffee can help eliminate distractions—acting as a filter to focus attention on the main task. This is especially valuable for work that requires concentration for extended periods, such as writing, coding, or studying.

Is it worth drinking coffee for better concentration?

Coffee can be an effective tool for supporting concentration, alertness, and productivity when used in moderation and mindfully. It works best when consumed at appropriate times, in reasonable doses, and in balance with rest and sleep.

For many people, a cup of coffee is not only a source of pleasure but also a way to work more effectively mentally. However, as with any supportive tool, the ability to use it properly is crucial.