How your brain works on caffeine

As Americans are becoming busier and busier, the dependence on one of the most ubiquitous drugs in the world has continued to evolve. The most common form it takes is in coffee, which has become mass produced and marketed through a multi-billion dollar industry. The prevalence of this beverage, however, is not simply a result of its ability to keep you awake, but also the reduced risk of diseases caffeine has been linked to. More than 54% of Americans over the age of 18 drink coffee everyday. Given that the majority of our nation consumes this beverage, observational research has been conducted to identify the effects it has on the human body.

The dose of caffeine will dictate the response the individual has. Acting as a mild stimulant, it affects the central nervous system of the human body. Within the brain, there are specific receptors for a chemical known as adenosine. As this chemical travels through the neural membrane, it will bind to these receptors and slow neural activity by inducing sleep. As a neurotransmitter, it sends chemical messages throughout the body, and in the case of adenosine, these messages are inhibitory. Caffeine works to counter this depression of the nervous system by working as an antagonist to these receptors. The primary chemical within coffee then binds to these sites instead of adenosine, which limits its ability to induce the sleepiness we seem to feel almost daily. It stimulates our activity by preventing adenosine from doing its job. Caffeine’s effect on the brain is not strictly on this chemical. Additionally, it stimulates the secretion of the hormone adrenalin from the adrenal glands. By activating the bodily response in the sympathetic nervous system, coffee drinkers become more attentive and receive energy from the innate fight or flight response that is elicited.

The benefits of improved performance on tasks in addition to feeling a greater sense of wakefulness is enough to keep many coffee drinkers on a daily consumption schedule. The attention and concentration boost, however, are only a few of the short-term benefits afforded to caffeine users. Further research suggests a wide array of long-term benefits available as well. Caffeine seems to have a neuroprotective feature that decreases the users’ risk of developing degenerative disorders such as Parkinson’s disease as well as Alzheimer's and dementia. Research in the past decade has also found evidence of caffeine preserving cognitive abilities in older adults and decreasing the risk of suicidal thoughts. Although we have yet to reach a point where research has yielded more empirical evidence of the potential disease prevention, the upside of this drug seems promising.

This being said, research has confirmed that physical dependence arises from continued consumption. As a result, when a user stops their normal intake, they can experience withdrawal symptoms. Headaches are most common as well as drowsiness and a marked decrease in concentration. These in conjunction with potential irritability and anxiety impact the individual’s mood and disrupt their ability to work and be productive. Symptoms are typically short term and vary in both degree and duration. Overall, it is important to recognize both the upside and downside of the drug and consume in moderation to maximize the benefits you accrue.

Sources:
http://www.coffeeandhealth.org/topic-overview/coffee-and-the-mind/
http://www.health.harvard.edu/blog/caffeine-healthy-diet-may-boost-memory-thinking-skills-alcohols-effect-uncertain-201406187219
http://emedicine.medscape.com/article/1182710-overview

Coffee by the Numbers

http://www.businessinsider.com/facts-about-the-coffee-industry-2011-11
http://thebrain.mcgill.ca/flash/i/i_03/i_03_m/i_03_m_par/i_03_m_par_cafeine.html
http://www.news-medical.net/health/What-is-Adenosine.aspx
http://www.aarp.org/health/healthy-living/info-10-2013/coffee-for-health.html