In some, caffeine can produce feelings of anxiety and even be a catalyst for a full-blown panic attack.
However, this occurs only in people who have a slight genetic variation in their adenosine receptors which are responsible for caffeine's awakening effects but also regulate a person's sense of anxiety.
The Science Behind Caffeine and Anxiety Disorders
A well-conducted study, published in 2003 which was a joint project in part by the Department of Psychiatry, The University of Chicago and The Department of Psychiatry, University of Munster, Germany 1 Adenosine receptors were likely responsible for caffeine-induced anxiety.
Newman's Own Organics Special Blend Keurig Single-Serve Medium Roast Coffee K-Cup Pods, 32 Count
The team looked at 3 different genotypes involving adenosine receptor genes to see if any of them would indicate whether or not a person would have increased anxiety when consuming caffeine.
They found that people with an A 2a receptor gene seem to be especially at risk of experiencing increased anxiety when consuming coffee, tea, energy drinks, or other caffeine-containing products.
Both the A 1 and the A 2a adenosine receptors in a person's brain are thought to also regulate how a person deals with stress and anxiety. Since caffeine binds to these receptors , it is thought to interfere with anxiety regulation.
Therefore, those who have the A 2a gene difference could experience increased anxiety when consuming caffeine. People in an already anxious state could be prone to full-blown panic attacks if they consume caffeine during this period.
In the study referenced above, participants were given just 150 mg of caffeine, which was enough to elicit anxiety in those with the gene variation. This is less than half the amount of caffeine found in a Starbucks Grande Coffee .
The study did not account for other factors such as caffeine tolerance since all the participants were nonhabitual caffeine users.
Yet another study published in The American Medical Journal 2 looked at people who were already diagnosed by the DSM-III criteria for agoraphobia with panic attacks or panic disorder and those with normal anxiety levels.
They evaluated each group's responses to caffeine. They found that within the diagnosed group, 71% reported feelings associated with panic attacks after consuming the caffeine.
Recommendations
Since most people, without genetic testing, would have no idea whether or not they have the A 2a receptor mutation, most people will have the safety of consuming caffeine based on their current history of anxiety and inclination towards panic attacks.
Those who experience anxiety and who are not habitual caffeine users should abstain from caffeine altogether. They should be aware of which products contain caffeine and avoid them.
Those who are daily caffeine consumers and who also suffer from anxiety should try to keep their daily consumption of caffeine fairly consistent. Consuming more caffeine than their usual amount could increase anxiety levels. This group should also be aware how much caffeine their favorite beverages contain and keep track of their daily consumption.
The aforementioned group should also consider cutting back on caffeine or quitting caffeine to better manage their anxiety and risk of panic attacks. Even habitual caffeine users could be at increased risk of panic attacks if life situations arise that cause increased stress and anxiety. Caffeine could "push them over the edge".
Exercise May Help Reduce Caffeine-Induced Anxiety
Additional research from the Department of Psychiatry, University of California, San Diego 3 found that regular exercise seems to lessen the degree to which caffeine heightens anxiety levels in those prone to anxiety.
In this study, researchers exposed to group of anxiety-prone men to both 60 minutes of cycling and 60 minutes of quiet rest after the administration of 800 mg of caffeine and then evaluated their level of anxiety after each test.
They found that rest did not have any effect on decreasing the level of anxiety reported, but the exercise did significantly reduce the level of anxiety reported by the participants.
So, the bottom line here is that exercise could lessen the degree to which caffeine causes increased anxiety in those already prone to problems with anxiety.