What is the most used drug in the world? It’s not nicotine or anything illegal.

It is caffeine.

And the most popular form it comes in is coffee. Many people joke that they can’t function without coffee. Others hate it.

Coffee has many clear health benefits, but also side effects especially if over-consumed.​ Here we present a balanced view backed by the latest scientific research.

Health benefit #1: Coffee increases your energy level

This is probably the most obvious of coffee. People drink it to feel less tired.

It is because caffeine is a stimulant drug. When you consume coffee, the caffeine is absorbed into your bloodstream. It then travels to the brain where it blocks the neurotransmitter adenosine.

Adenosine is an inhibitory neurotransmitter. Though it helps in energy transfer, it acts as a depressant of your central nervous system. This means it suppresses arousal and promotes sleep. Usually, the levels of adenosine in your brain rises each hour you’re awake, making you more and more sleepy.

When blocked, other neurotransmitters such as norepinephrine and dopamine increase. This is what causes the stimulant effect. Firing of neurons is increased. As a result, you’re more awake.

Many researches show that coffee improves: memory, mood, reaction speed, vigilance and general cognitive function.

So in addition to increasing your energy level, coffee also makes you . . . well, smarter.