What Does Caffeine Do to the Body?

Drug Classification:

It is most important to know that caffeine is a natural nervous system stimulant. This means that it increases the speed at which chemical reactions occur in the body and in the short term it gives you more energy. It is also a diuretic, which means it increases production of urine, which can dehydrate you. In its pure form it is a white crystalline xanthine alkaloid type powder. Caffeine is found in over 60 different plant species, and is used as a pesticide to keep small bugs from eating any plants consuming caffeine. In higher doses caffeine can be toxic, and there have been reports of people going to the hospital and even dyeing from large caffeine consumption. For most normal people ingesting this much caffeine is impossible. Most of the cases of caffeine abuse are about people taking caffeine pills, or drinking straight espresso. In other words caffeine is quite safe, and is said to be consumed by 90% of the world’s population on a regular basis.

How Caffeine Works In Your Body:

Caffeine works by crossing the blood-brain barrier, causing it to travel to the brain where its real effects begin to take place. In the brain caffeine simulates adenosine. Adenosine works to slow down nerve activity and make you feel more drowsy by binding to adenosine receptors. This process is going on in your body every day from when you wake up to when you go to bed. When caffeine is added to this equation the adenosine receptors bind with it instead of adenosine, and instead of making you feel drowsy the caffeine speeds up nerve activity. When the pituitary gland sees this brain activity it starts to think an emergency is going on which causes it to excrete adrenaline. The absence of adenosine and the addition of extra hormones in the body cause you to feel awake and energized as long as caffeine is still in your system.


There are many effects of caffeine. The positive include increased attention, alertness, metabolic rate and decreased fatigue. On the other hand consuming caffeine puts your body through unnecessary stress which can have negative effects such as increased anxiety, blood pressure, reduced control of fine motor movements and dehydration. Also it should be noted that consuming caffeine (especially before bed) can have adverse effects on the quality of sleep. So keep consumption in moderation.


A safe amount of caffeine is under 400mg per day. This equals about 3-4 coffees. I recommend you try to stay well below this, unless you have an especially important event on that day. At this amount it is also important to take a day or two off caffeine every once in a while. This helps the body get some time to relax and reset itself. Too much caffeine can lead to caffeine addiction.

Source by Dylan McLauchlan