Caffeine is a stimulant that can be found naturally in plants we use to make coffee, tea, and chocolate. Even though many people believe caffeine to be a supplement, that is not the case. Caffeine is the world’s most used psychoactive drug, and, contrary to most, it is legal.

Caffeine affects your body in multiple ways. Many of us rely on caffeine every day to reduce fatigue and increase focus. Caffeine temporarily increases our energy and alertness, but it can also cause irritability, anxiety, nausea, and headaches, as well as negatively affecting our sleep.

How does it work?
For every hour that we stay awake, a compound called adenosine starts to pile up in our brain, binding to certain receptors that gradually increase our need for sleep. Eventually, this need becomes so strong that sleep becomes inevitable, whether we like it or not.

However, there is a way around this. Caffeine binds to the same receptors as adenosine, blocking it from sending signals to our brain and allowing us to stay awake even though the amount of adenosine has come to a critical point. Nevertheless, consuming caffeine does not stop adenosine from piling up in our brain, resulting in a so-called caffeine crash when our body finally breaks down the caffeine, freeing the adenosine.

Caffeine has a half-life of about six hours, meaning that six hours after being consumed, 50% of the caffeine is still in effect. Even though you might find it easy to sleep after consuming caffeine, it does not mean that you sleep well. Caffeine impairs our sleep quality significantly, especially when it comes to our deep sleep. Deep sleep is essential for all human beings, contributing greatly to muscle growth/repair and waste removal in our brain, allowing us to feel invigorated after a good night’s sleep. Thus, it is recommended to minimize the consumption of caffeine in the afternoon, promoting better sleep.

Side Effects and Withdrawal Symptoms
Caffeine is usually harmless when consumed in moderate amounts. However, it can cause various side effects, such as tremors, dizziness, rapid heartbeat and breathing, high blood pressure, headaches, nausea, irritability, and stress. When you consume caffeine regularly, your body develops a tolerance to it, making you less responsive to its effects. For this reason, many people become dependent on caffeine and experience withdrawal symptoms once they stop consuming it. These withdrawal symptoms include headaches, muscle pain and fatigue. Withdrawal from caffeine is not considered dangerous but it is recommended to gradually reduce the consumption to minimize discomfort.

Moderate amount
Caffeine should be consumed moderately, 400mg a day (4-5 cups of coffee) has been cited as a safe amount. Of course, this varies between individuals, some people are more sensitive to caffeine than others, and it is important to take body weight, health, and caffeine tolerance into account. Women who are pregnant or nursing are advised to limit their consumption to 200mg a day. Caffeine consumption can be harmful to children and teenagers, and should, therefore, be avoided. Caffeine has no nutritional value, so there is no need for it in our diet.

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