Caffeinated Beverages Affect Adult Brain

Keywords: caffeine, beverages, coffee, tea, chocolate, decaffeinated coffee, herbal tea, caffeinism, intoxication, tolerance, withdrawal, anxiety.


Caffeinated Beverages Affect Adult Brain. What are caffeinated beverages?  Effects of caffeinated beverages on the brain? How much caffeine should an adult take? Who can take caffeinated beverages?

The term beverages comprises of all drinkable liquids. These include water, alcoholic drinks, juices, coffee, tea, cocoa drinks, milk, soft or carbonated drinks like cola, etc. Others are energy drinks, smoothies, herbal drinks, etc.

Their main functions are to provide nutrients, energy and hydration. They can be taken in private or in social gatherings. Incidentally, these beverages affect not only the physical health, but also the mental health. The effects on mental and behavioural health can be both positive and negative.

What are caffeinated beverages? 

Caffeinated beverages are drinkable liquids that contain caffeine. And caffeine is a psychoactive drug that is found in many plants. It is psychoactive in the sense that it has a strong effect on the brain. By this, caffeine is able to affect the brain neurotransmitters in such a way as to affect brain function.

Examples of caffeinated beverages include coffee, tea, chocolate drinks, cola soft drinks, energy drinks and some over the counter medications.

Effects of caffeinated beverages on the brain?

Putting it in a short form, caffeine stimulates the brain, by causing the increase in the brain neurotransmitters such as dopamine, norepinephrine, etc.

Caffeine acts immediately, within 20 minutes to one hour after consumption. And it is mainly absorbed from the stomach and small intestine. After absorption into the blood stream, caffeine quickly moves into body cells, including the brain.

The good:

At low dose, caffeine gives a desirable effect such as increasing alertness, reducing fatigue or tiredness and elevating ones mood. That is give caffeine makes the person happy.

When taken at low or normal dose, caffeine can also improve attention and concentration, work and study performance. It improves learning and remembering.

As it increases alertness, it also increases vigilance. It also increase the speed with which the brain processes information and creative thinking.

In normal dose, caffeine can keep one from developing depression, anxiety and has a low risk for suicide.

When it comes to cognitive decline in aging, caffeine has reduced the risk of developing dementia and Parkinson’s disease. So it reduces the decline in memory as one ages.

The bad:

When caffeine is taken in excess, it cause anxiety in some people, especially to those who are sensitive to it.

Mental health issues –

Caffeine can bring about, increase and maintain anxiety, when taken above the recommended dose or in sensitive people. And it can provoke panic attack.

The anxiety disorders include phobias, etc.

People who suffer from psychosis, like schizophrenia, by taking caffeinated drinks are prone to increased delusions and hallucinations. But then, even people without psychotic disorder, can also have increased delusions and hallucinations with excess caffeine intake.

When taken in excess, it can predispose one to major depressive disorder as well as personality disorder. And high intake of caffeinated drinks can predispose one to having mania. This high intake can also cause excitement, irritability, agitation and aggression.

Taking caffeinated beverages, can decrease the absorption of certain medications such as antipsychotics. It can also increase the side effects of some of these medications.

Sleep issues –

Caffeine containing beverages can also affect sleep negatively. Being a stimulant, caffeine can keep one awake, thus causing poor sleep. It does this by delaying falling asleep and causing multiple wakes in the night. Taking caffeinated drinks even up to 6 hours before bedtime can still negatively affect sleep.

Substance abuse issues –

Caffeine intake will also potentiate the intake of hard drugs such as cocaine, alcohol and smoking. This is more in those who are addicted to hard drugs. And for such people, by smoking or taking alcohol their liver can metabolize or degrade caffeine much faster. Thus making the person want to drink more of the caffeinated beverage.

Physical issues –

Because of the blood flow effects of caffeine on the brain, it can cause headaches. Caffeine can also bring about dehydration because it causes a lot of urination.

The ugly:

Caffeine being a stimulant is also a substance of abuse. And for this, some people can become addicted or have dependence on caffeine. Thus he or she can become intoxicated, have tolerance and withdrawal symptoms from the ingestion of caffeine.

Excessive intake of caffeine can cause intoxication called caffeinism. When this happens, the person will become agitated, restless and excited with poor speech and poor sleep.

In some people after long term of use of caffeine at a particular dose, they will develop what is called tolerance to caffeine. This means that they have to take higher dose of caffeine to get the good effects from the caffeine.

And for people who are on high dose of caffeine, when they suddenly stop the intake, they develop what is called the withdrawal symptoms.

Withdrawal symptoms include headache, being irritable, sleeplessness, confusion and urge to vomit. There are also anxiety symptoms like restlessness and tremor, fast heart beats and raised blood pressure. These symptoms get worst by 1–2 days of not taking the caffeine and stops within a few days. The withdrawal symptoms are relieved by taking caffeine.

How much caffeine should an adult take?

Different people use caffeine for different reasons. The medical personnel use caffeine to increase their alertness and reduce tiredness. People in sports use caffeine to increase their physical performance. Then generally, adults take caffeine for the taste and to increase their energy to work or study. Others use it in social gathering to enhance their status.

But many people can overdue their intake to the point of causing them physical and psychological harm. So how much of caffeine in beverages are actually safe?

The amount of caffeine in beverages vary due to the source from which the beverage comes from. They also differ due to the processing method in the factory and how hot the water you infuse into them is. The hotter the water you use to make your beverage, the more the caffeine content is released. For example, if you are using tea bags, the hotter the water, the more the caffeine content you will get. And the longer you leave the bag(s) in the cup, the more the caffeine content of the water in the cup.

Also, different types of coffee contain different amounts of caffeine. Then a regular can of cola drink can have as high as 40mg. And an average can of energy drinks has up to 80mg or more of caffeine.

It is important to note that there are different types of coffee, different types of tea, etc. And we should know also that even decaffeinated coffee contains some quantity of caffeine. But herbal teas don’t have caffeine, because they are not teas in the actual sense of the word. They are made from dried fruits, flowers, spices, or herbs.

The varieties of tea include black tea, green tea, white tea and herbal tea. These can come in bags or as dried loose crushed leaves.

Safe levels of caffeine in beverages:

The American Food and Drug Administration considers 400mg daily of caffeine or lower, in beverages as safe for healthy adults.

One aspect of caffeine ingestion is that it is not a ‘one size fit all.’ And it is easy for one to know what quantity of caffeine suits oneself.

If you try a certain quantity of caffeine and it doesn’t suit you, then you can lower the amount. You can also change to a different brand of product or beverage. This will enable you to get the type that suits you or is safe for you.

It is important to know that the amount of caffeine in these beverages differ. So let us take the beverages separately.

One level teaspoon of instant coffee, contains about 30mg to 90mg of caffeine. So one table spoon has 90mg to 180mg of caffeine.

And one level teaspoon of decaffeinated coffee contains approximately 6mg of caffeine. This removes about 97% of caffeine from normal coffee.

For chocolate drinks, one level table spoon of the cocoa powder, contains 12mg of caffeine.

One tea bag has 30mg – 50mg of caffeine. But the amount of caffeine that gets infused into the cup depends on two factors. These two factors are, how hot the water is and how long the tea bag is let in the cup.

A regular size of can cola soft drink will contain about 34mg to 38mg of caffeine.

As for energy drinks, a regular can size contains 170mg – 200mg of caffeine. But there are more concentrated shots of energy drinks that can have between 100mg to 200mg per shot.

When best to take caffeinated beverages:

Caffeine beverages are not recommended to take as soon as you rise from the bed. One reason is that, when we wake up in the morning, the level of a hormone called cortisol is high. Cortisol rises as soon as we wake up and helps to boost our wakefulness. But as the day passes, the level reduces. So if one takes caffeinated beverages as soon as he or she wakes, it keeps the effect of cortisol high. High level of cortisol is not good for health.

The recommendation is that, the first caffeinated drink in the morning, should come between 30 to 120 minutes after waking. This will give enough time for the level of cortisol to reduce.

Another good time to take these beverages is in the afternoon. But note that taking a caffeinated drink 6 hours or less before bedtime, can prevent you from sleeping well.

For example, if you go to bed by 10pm, then, keep off these beverages from 2pm or 3pm. If you take caffeine by 4pm, you may not sleep at night.

Who can take caffeinated beverages?

There are benefits from consuming caffeinated drinks, comprising of physical and mental health effects, including being an antioxidant.  These notwithstanding, not everyone should consume these drinks, due to their down sides.

Choosing which caffeinated beverage is good for you, will depend on your type of work and your health condition.

Mental health:

If you have any mental illness such as anxiety, you should not take caffeinated drinks. These anxiety disorders include generalized anxiety disorder, social phobia, panic disorder, etc.

Also, if you are already suffering from a major depressive disorder, caffeinated drinks are not for you. If you have other mental illnesses such as schizophrenia, keep off caffeinated beverages. And caffeinated drinks prevent the proper absorption of antipsychotic medications, thus lowering their effects.

During the times of stress, it is advised that you do not take caffeinated beverage. This is because it can affect your sleep and your blood pressure, negatively.

Persons that abuse substances such as alcohol, cannabis, cocaine, etc. should stay away from caffeinated beverages.


If you are sensitive to caffeine in foods and drinks, then caffeinated beverages are not for you. For such people, even a little amount of caffeinated drink, can make them jittery. But if you can withstand a little amount of caffeine, then switch to taking teas. And also reduce the number of cups you take daily. You can also take decaffeinated coffee.

Physical health:

People who suffer from hypertension and heart diseases, should keep off these beverages. Or if you have sleep problems, keeping off caffeine is the best. But if you cannot, then lower your intake. Lowering your intake of caffeine in cardiovascular diseases, have been shown by some researchers, to not affect these conditions. These researchers believe that at low dose, caffeinated drinks do not cause or increase these conditions. Cardiovascular diseases include heart disease and hypertension, etc.

If you suffer from migraine headaches, you are pregnant or breast feeding, it is better to keep off caffeine. But if you must take, then go for teas, including herbal tea or decaf. coffee. The less time you brew your tea, or the less hot the water, the less caffeine in the cup. Note that caffeine intake up to 300mg per day can cause miscarriages and still birth in pregnant women. Also, it is important to know that a baby in the womb exposed to caffeine may suffer from childhood obesity.

Persons suffering from heart burns or peptic ulcers will do well to keep off caffeine because they increase stomach acid.

Caffeine can make you urinate a lot. So if you have any disorder or on any medication that will increase urination, caffeine will make it worse.

For those suffering from glaucoma, taking caffeine can make it worse. And for those suffering from epilepsy, caffeine may increase the seizures.

Caffeinated Beverages Affect Adult Brain. Share to friends.

Share with friends!!!