What happens in your brain when you drink coffee?

Caffeine triggers a series of neurochemical processes. How does it affect us?

Many people start their day with a good cup of coffee.. This substance has reached throughout history a very high level of popularity, being drunk by about 80% of the adult population and being an element widely present in everyday life, its consumption being used even as a pretext at the time of socializing.

Coffee helps to clear the mind, increase the level of activation and improve attentional capacity. But how can coffee affect us in this way? But how can coffee affect us in this way? What happens in your brain when you drink coffee?

Caffeine, an excitatory substance

Caffeine, one of the main components of coffee, has, as we already know, psychoactive effects on our brain. Due to the effect they produce on the nervous system, they form part of the psycho-stimulant substances or psychoanaleptics, substances characterized by producing an increase in the activation and cerebral metabolism, generally increasing the level of activity of the organism.

However, within this group, caffeine is considered a minor activator, forming, together with theophylline and theobromine, the group of substances known as xanthines. This group, although it presents activating effects in the organism, has a much less potent action than that of other excitatory substances and many fewer secondary effects, and it is not frequent that they present serious adverse effects.

Caffeine takes a few minutes to reach the brain, and its effects tend to last between four and six hours.. It is not uncommon to consume it several times a day, without this having to be dangerous due to its low addictive potential. In spite of this, its regular consumption ends up producing certain levels of tolerance, each time a greater quantity or frequency of the substance being necessary to provoke the same effects as at the beginning.

Action at brain level: mechanisms of action

Around five minutes after drinking a cup of coffee, caffeine begins to exert its effects on the nervous system. This substance acts in different ways throughout the nervous system, interacting and provoking effects on different types of neurotransmitters.

The activating effect of coffee is mainly due to the action on a hormone called adenosine, a hormone that contributes to maintain a state of calm and relaxation by inciting the suppression of brain activity as well as to maintain medium or low levels of other hormones such as dopamine and noradrenaline. Caffeine acts as an antagonist of the adenosine receptors, affecting its absorption in such a way that it inhibits its reuptake by the neurons. This action results in an increase in brain activity and in the intensity of the transmission of nerve signals by allowing an of nerve signals by allowing greater action by other hormones such as dopamine.

Brain reward system

In addition to its effect on adenosine, caffeine also interacts with other neurotransmitters. Another of the great effects of caffeine on the brain is the increased release of dopamine, which activates the brain's reward mechanisms to induce a state of well-being.

However, while other substances such as cocaine activate the whole system (which facilitates its enormous addictive potential), caffeine and xanthines tend to provoke an increase in dopaminergic release in more specific areas such as the caudate nucleus and the prefrontal cortex. In this way, an activation sensation is achieved, to a certain extent pleasant, but without activating the whole brain reward system.

Caffeine in turn stimulates the noradrenergic and cholinergic systems, producing an increase in activation and an improvement in the capacity for concentration and information processing. and information processing.

Finally, it is important to highlight that the consumption of caffeine causes an increase in the levels of cortisol, known as the stress hormone, and adrenaline. This effect helps to induce a state of activation at a physiological level that allows us to remain alert and attentive. However, it can also cause distress or negative stress that can lead to maladaptive behaviors, cardiac acceleration or anxiety.

Beneficial Effects

The consumption of coffee can bring numerous benefits as long as it is consumed prudently and without excesses. Some of the positive effects that coffee has on the organism are as follows.

1. Increases wakefulness and decreases the level of tiredness.

The fact that caffeine inhibits the action of adenosine and potentiates an increase in cortisol and other excitatory hormones causes the level of consciousness to remain elevated, thus causing the levels of tiredness and fatigue that the body may be experiencing to be reduced.

2. It favors the attentional and learning capacity.

By maintaining the level of consciousness and reducing the sensations of fatigue and tiredness, the subject's attention span is also increased, allowing him/her to use and distribute his/her physical and cognitive resources more efficiently and for a longer period of time.

In addition, it allows nerve impulses to be transmitted with great intensity, which can favor the acquisition of new learning and the reinforcement of existing ones.

3. It has a protective effect against certain dementias.

Recently, research has been conducted on the possible role that caffeine consumption may have in contributing to the prevention of certain dementias.

Specifically, its regular consumption may serve as a protective factor against Parkinson's and Alzheimer's disease by stimulating the dopaminergic, cholinergic and noradrenergic systems and having antioxidant effects that reduce the number of free radicals present in the system.

4. Accelerates metabolism

The increased activity produced by caffeine usually translates into a state of physiological excitation accelerating the metabolism not only of the brain but of the whole body. It has been demonstrated that the consumption of coffee before physical exercise helps to break down the fat in our body.

In addition, this acceleration usually leads to an increase in physical activity, which not only facilitates fat burning, but also predisposes the organism to perform activities that allow fat loss.

5. Diuretic effect

Caffeine also has an important diuretic effect. It has been demonstrated that it stimulates the production of urine, helping to excrete elements that are harmful to the body.

It also has antiemetic effects if consumed in moderation, preventing the onset of vomiting and reducing the level of nausea,

Potential Harm

One or several cups of coffee a day can have a positive effect on our brain, but, as with most substances and substances that have a positive effect on the brain, it can also have a negative effect on the brain.s with the majority of substances and foods consumed, an excess can have adverse effects.

1. Sleep problems

As mentioned above, caffeine causes a decrease in the sensation of fatigue or tiredness.

While it may increase alertness in people with daytime sleepiness, depending on how, when and how much is consumed, it may cause the individual to be unable to fall asleep. may cause the individual to be unable to fall asleep, with insomnia being the most frequent effect.The most frequent effect is insomnia of conciliation.

2. Anxiety disorders

The elevation of the amount of cortisol and adrenaline produced by coffee causes an increase in the excitability of the subject who has consumed it. Although in some circumstances it can be favorable in terms of learning or acting efficiently, in other occasions this increase generates a higher stress than the individual is able to handle, and anxiety reactions may appear.and anxiety reactions may appear.

In fact, caffeine consumption is not recommended for stressed individuals or those with anxiety-related disorders.

3. Agitation, tachypsychia and logorrhea

While the increased activation produced by coffee may be desirable in low doses, in higher quantities caffeine can provoke the presence of agitation, tremors (and even epileptic seizures)..

At a cognitive level, the presence of tachypsychia or accelerated thinking can also occur, in which frequently there is a flight of ideas or loss of the train of thought. Another common symptom is logorrhea.

4. Stress and irritability

The increase of activation in the nervous system and the slightly more expansive mood than usual, as well as the increase of the level of the nervous system.as well as the increase in the level of stress that coffee generates, cause that sometimes the person who has consumed caffeine has a tendency to be aggressive or irritable in front of stimuli that would not usually be aversive.

5. Cardiac effects

The consumption of caffeine is not usually recommended for people with cardiac disorders.The use of this product may induce tachycardia and arrhythmias, which in people with a certain standard of living and certain pathologies could lead to a Heart attack or even cardiorespiratory arrest.

6. Risk of death

Although a high quantity is usually necessary, the consumption of quantities exceeding ten grams of caffeine can induce epileptic seizures, or cardiorespiratory problems that could culminate in the patient's death..

7. Abstinence Syndrome

It has also been discussed that caffeine can, with prolonged and frequent consumption over time, can lead to withdrawal syndrome.. This syndrome translates into the presence of excessive drowsiness, nausea and vomiting, anxiety and/or depression after abrupt cessation or reduction of consumption.

8. Other aspects

The elevation of mood and the high level of activity that caffeine consumption may produce in some people, making it not suitable for people with certain characteristics.. For example, in mood disorders (for example during manic episodes in the case of bipolar disorder) or in psychotic disorders.

Bibliographic references:

• American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders. Fifth edition. DSM-V. Masson, Barcelona.

• Glade, M. J. (2010). Caffeine - not just a stimulant. Nutrition, 26(10), 932-938.

• Macedo, J. (n.d.). Drinking coffee: advantages and disadvantages of its consumption. [Online] Available at: https://psicologiaymente.com/neurociencias/beber-cafe-ventajas-desventajas

• Salazar, M.; Peralta, C.; Pastor, J. (2006). Manual de Psicofarmacología. Madrid, Editorial Médica Panamericana.

• Smith, A. (2002). Effects of caffeine on human behavior. Food and chemical toxicology, 40(9), 1243-1255.