Coffee is the second most consumed beverage in the world after water. At least a billion people drink at least a cup of coffee each day. There are many long term positive health effects from drinking coffee including protection from developing type II diabetes and various types of cancer and neurodegenerative diseases like Alzheimer’s and Parkinson’s diseases. The other side of the coin is that drinking too much coffee can cause side effects such as gastritis and the jitters. What is it about coffee that causes side effects? Just why does coffee give you the jitters.
What Are the Jitters?
Jitters refers to a state of hyper alertness, restlessness, and nervousness accompanied by a fast heart rate, physical shaking of the legs, sweaty palms, and a shaky voice. Jitters can be cause by emotional stress or by chemical stimulants. In regard to coffee it is the caffeine in coffee that blocks neurotransmitters that can have calming properties and rather stimulates the nervous system mimicking psychological stress.
Caffeine Effects on the Human Body
When you ingest caffeine it blocks adenosine which is a neurotransmitter that relaxes us and makes us sleepy. This is part of the “wake up” effect of a morning cup of coffee. Blockage of adenosine results in neurons firing faster while the brain releases norepinephrine and dopamine. These neuro transmitters are responsible for arousal and alertness. In excess their release causes the same symptoms as extreme anxiety with a fast heart rate and extreme restlessness.
Fight or Flight Response to Drinking Too Much Caffeine
Humans have confronted dangerous situations throughout virtually all of the existence of the species. When confronted with a dangerous situation a person goes into an automatic response that helps equip them for survival. This physiological response to danger was described at the beginning of the 20th century by Walter Cannon, a physiologist. The sequence of events prepares the body to most efficiently run away or fight for one’s life. A common problem in modern life is that all too often situations or chemicals that do not represent a threat to one’s life still provoke the same physiological response that being pursued by a bear, lion, or pack of hyenas might have in ancient times. Drinking too much coffee with a high caffeine content falls into this category. Physical threats to one’s life cause activation of the brain location called the amygdala which then turns on a host of neuro transmitter responses. Too much caffeine shortcuts this process by directly turning on responses that increase the heart rate and increase awareness. Thus a response that helped humans survive in the early days of the species is replicated with two or three cups of strong coffee back to back.
Are The Jitters from Coffee Dangerous?
The nervous effects of drinking too much coffee with too much caffeine are typically short term, lasting no more than a few hours and typically peaking in an hour or so. If a person suffers from high blood pressure or cardiac rhythm issues these can be complicating factors. However, over the long term jitters from coffee do not pose a health risk but rather an inconvenience. If person has a problem with severe esophageal reflux this problem can be worsened by too much caffeine. Long term reflux can lead to esophagitis and a stricture which be a serious health risk albeit not related to the jitters.