What happens in your brain when you drink coffee?

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

Coffee helps to clear up, increase the level of arousal and improve attention span. But, How can coffee affect us in this way? What happens in your brain when you drink coffee?

Caffeine, an exciting 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 are part of psychostimulant or psychoanalptic substances, substances characterized by producing an increase in brain activation and metabolism, generally managing to increase the level of activity of the brain. 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 powerful action than that of other excitatory substances and much less side effects, not being frequent that they present adverse effects serious.

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

Action at the brain level: mechanisms of action

About five minutes after having a cup of coffee, caffeine begins to exert its effects on the nervous system. This substance acts in various ways throughout the nervous system, interacting and causing effects in different types of neurotransmitter.

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

However, while other substances such as cocaine activate the entire system (facilitating its enormous addictive potential), caffeine and xanthines usually cause an increase in dopaminergic release in more specific areas such as the caudate nucleus and the prefrontal cortex. In this way, a somewhat pleasant sensation of activation is achieved, but without the entire brain's reward system being activated.

Caffeine in turn stimulates the noradrenergic and cholinergic systems, producing an increase in activation and an improvement in the ability to concentrate. and information processing.

Finally, it is relevant to note 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 physiological level of activation that allows you to remain alert and attentive. However, it can also cause distress or negative stress that can lead to maladaptive behaviors, heart racing or anxiety.

beneficial effects

The consumption of coffee can bring many benefits as long as it is done prudently and without excesses. Some of the positive effects that coffee has on the body are the following.

1. Increases wakefulness and decreases the level of fatigue

The fact that caffeine inhibits the action of adenosine and enhances an increase in cortisol and other excitatory hormones causes the level of consciousness remains elevated, which causes the levels of tiredness and fatigue that the body may be experiencing are reduce.

2. Promotes attention and learning capacity

By causing the maintenance of the level of consciousness and the reduction of feelings of fatigue and tiredness, the attention span of the subject also rises, causing him to use and distribute his physical and cognitive resources more efficiently and for longer weather.

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 carried out on the possible role that caffeine consumption may have in helping to prevent certain dementias.

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

4. Speeds up metabolism

The increased activity produced by caffeine usually results in a state of physiological arousal, accelerating the metabolism not only of the brain but of the entire body. Drinking coffee before exercising has been shown to help break down fat in our bodies.

In addition, this acceleration usually involves an increase in physical activity, which in addition to facilitating the burning of fat predisposes the body to carry out activities that allow it to lose it

5. Diuretic effect

Caffeine also has an important diuretic effect. It has been shown to stimulate urine production, helping to excrete elements that are harmful to the body.

It also has antiemetic effects if consumed moderately, preventing the appearance of vomiting and reducing the level of nausea,

Possible damages

One or several cups of coffee a day can positively affect our brain, but cAs in most substances and foods consumed, an excess can have adverse effects.

1. Sleeping problems

As we have mentioned before, caffeine causes a decrease in the feeling of fatigue or tiredness.

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

2. Anxiety disorders

The increase in 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, on other occasions, said increase generates a stress greater than that which the individual is capable of handling, and anxiety reactions may appear.

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

3. Agitation, tachypsychia, and logorrhea

While the increased activation produced by coffee may be desirable in low doses, in higher amounts caffeine can cause agitation, tremors (and even seizures).

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

4. Stress and irritability

Increased activation in the nervous system and slightly more expansive mood than usual, as well as the increased level of stress generated by coffee, sometimes cause the person who has consumed caffeine has a tendency to be aggressive or irritable in the face of stimuli that generally would not be aversives.

5. Cardiac effects

The consumption of caffeine is also not usually recommended for people with heart disorders., since it can induce tachycardias and arrhythmias than in people with a certain standard of living and with certain pathologies it could lead to a heart attack or even stops cardiorespiratory.

6. Death risk

Although a high amount is usually necessary, consuming amounts that exceed ten grams of caffeine can induce epileptic seizures, or cardiorespiratory problems that could lead to the death of the patient.

7. Abstinence syndrome

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

8. Other aspects

The elevation of the mood and the high level of activity that It can produce caffeine 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. (s.f.). 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 of Psychopharmacology. Madrid, Editorial Médica Panamericana.

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