As many of you probably know, Dunkin Donuts gives out free coffee on the Monday after a Penn State football victory. So, while I was sipping my free medium hazelnut coffee this morning, and that familiar anxious feeling started to come upon me, I began to wonder: why exactly does caffeine give some people the jitters? And why only some people, and not others?

Caffeine is the most widely-used psychoactive drug in the world, and it is no wonder why. Caffeine exists in more than 60 plant species throughout the world. Many people feel as though they could not get by without the boost of energy that caffeine, whether in the form of coffee, soda, or energy drinks, provides them. The science behind caffeine’s “pick-me-up” effect lies in its effect on the brain. According to this article, caffeine blocks adenosine receptors in the brain, stimulating the central nervous system, specifically, the hippocampus, cerebral cortex, cerebellar cortex, and the thalamus. Blockade of these receptors also allows for the release of adrenaline which results in stimulation of the sympathetic nervous system. This can cause a person to feel more alert and focused, and less fatigued. However, caffeine does not just affect the brain. Consuming caffeine also stimulates cardiac muscle, and at high doses, can cause tachycardia of the heart. All of these effects culminate in what is known as “caffeinism,” the anxiousness, restlessness, and agitation that one feels when they drink high doses of caffeine.

However, the line between a moderate and a high dosage of caffeine is hard to define for different people. One’s sensitivity to the effects of caffeine is influenced by his/her gender, weight, caffeine consumption habits, and proneness to anxiety, according to this article. Focusing for a moment on “proneness to anxiety,” we can see that the results of this study are consistent with the hypothesis that patients with anxiety disorders are more likely to experience caffeine-induced anxiety than are medical inpatients. In other words, people who are more prone to anxiety are also more prone to the anxiety-inducing effects of caffeine than others are. In summary, all these factors affect how someone’s body will react to caffeine, which might be the reason why I, an 18-year-old female who seldom drinks coffee and who has a tendency to be anxious, am more sensitive to the effects of caffeine than say, someone who drinks coffee everyday and rarely gets anxious.

All in all, people often forget that caffeine is a drug because it is such a prevalent part of our everyday routine as a society. It is perfectly mainstream to drink a cup of coffee every morning to start your day. However, it is important that people know what effect caffeine has on their body and why so that they can limit their consumption. The goal is to find a cup of coffee that produces the desired “energy boost” without reaching the point of caffeinism, which puts stress on the brain and the heart. Due to a variety of factors, the size of this cup will be different for everybody. For me, I think I’ll just stick to my free cup every victorious Monday.