Caffeine is the most widely consumed psychoactive substance in the U.S. and the world. A study in the Food and Chemical Toxicology journal on caffeine intake in the U.S. found that roughly 85% of Americans consume caffeine. The same study found that 96% of caffeine consumed via beverages is from drinking coffee. Globally, around 1.6 billion cups of coffee are consumed daily.
Coffee has become an indispensable part of modern culture and living. Workplaces and productivity rituals are centered on the dark brew, while coffee shops are a nexus for socializing and connecting.
For all of its overarching popularity and adoration, coffee, like any other psychoactive substance, comes with its fair share of downsides and adverse effects. Certain segments of the population have an increased sensitivity to the adverse effects of caffeine, while other individuals might have genetic-based vulnerabilities to caffeine. Studies have found that caffeine increases anxiety in younger populations, especially those with panic disorders. Infamously, caffeine also affects sleeping patterns and sleep quality.
When caffeine intake is suddenly reduced or ceased after consistent consumption, caffeine withdrawals can also cause a range of detrimental effects. One of the most common symptoms is headaches. The link between caffeine and headaches is still being investigated, with some studies reflecting that it assists in alleviating headaches and migraines, while others claim that it causes them.
Getting a clear view of the relationship between caffeine, headaches and caffeine withdrawals requires an in-depth examination of caffeine’s mechanisms of action and the current scientific literature findings.
Caffeine’s Mechanisms of Action
Caffeine works, in part, by influencing the neuromodulator adenosine. Adenosine regulates how neurons respond to the excitatory or inhibiting effects of neurotransmitters, i.e., chemicals that facilitate brain and nerve communication.
In particular, adenosine inhibits excitatory neurotransmitters that produce sensations of alertness and wakefulness. As per Matthew Johnson, Ph.D., Professor of Psychiatry and Behavioral Sciences at Johns Hopkins, adenosine concentrations increase in our bodies throughout the day to ensure that we are not too stimulated to sleep at night. Caffeine attaches to adenosine receptors on our nerve cells, reducing their effects and making us feel less sleepy.
Caffeine also causes other biological changes, such as lung bronchial dilatation and increased coronary blood flow around the heart.
Can You Get Headaches From Caffeine Withdrawal?
Caffeine withdrawal is a recognized diagnosis as per the American Psychiatric Association’s (APA) Diagnostics and Statistical Manual’s (DSM) latest edition, DSM-5. The DSM is recognized as the leading authoritative scientific text on mental disorders.
The DSM-5 acknowledges that headaches from caffeine withdrawal are genuine symptoms. Other symptoms include irritability, decreased focus and fatigue. A study in the peer-reviewed Psychopharmacology journal found that caffeine withdrawals affect cerebral blood flow and electrical activity in the brain.
It is clear that headaches from caffeine withdrawal or a lack of caffeine relative to one’s regular consumption are genuine physiological phenomena.
Why Does a Lack of Caffeine Cause Headaches?
José Lemos, Professor of Microbiology and Physiological Systems at the University of Massachusetts Chan Medical School, states that headaches from caffeine withdrawal are caused by the sudden increase in the effects of adenosine after caffeine stops inhibiting the neuromodulator.
The brain and nervous system are suddenly flooded with more adenosine; as such, feelings of drowsiness and fatigue, which adenosine causes naturally, take hold.
Caffeine withdrawal can impact blood flow in the brain, which is why, according to Professor Lemos, headaches from caffeine withdrawal can mimic migraine-like symptoms.
The unwelcome effects of caffeine withdrawal can even be part of a cycle that leads to Caffeine Use Disorder, a condition recognized by the DSM-5 as a problematic and concerning consumption pattern of caffeine.
How Long Do Caffeine Withdrawal Headaches Last?
Headaches from caffeine withdrawal, alongside other caffeine withdrawal symptoms, generally appear 24 hours after caffeine consumption has stopped. Some symptoms last up to a week — peaking in a couple of days — but headaches from a relative lack of caffeine can endure for three weeks.
If someone experiencing headaches from caffeine withdrawal consumes caffeine, they can achieve symptom relief in as little as two hours.
How To Manage Caffeine Withdrawal Headaches
Going cold turkey is not the most effective and pleasant way of cutting caffeine out of one’s life. To avoid falling into a cycle of caffeine dependence and bypass the dreaded headaches from caffeine withdrawal, a gradual decrease in caffeine consumption is wise.
To taper off your coffee intake, swap out your regular brew for decaf and choose a drink with less caffeine than regular coffee, such as black tea.
It can also be helpful to restrict your consumption of these beverages to certain times of the day. For example, one can commit to not drinking caffeinated beverages after the early afternoon. Drinking enough water can also assist in lessening headaches from caffeine withdrawal.
Does a Lack of Caffeine Cause Headaches?
While a lack of caffeine in and of itself does not cause headaches, caffeine withdrawals are a common cause of headaches and migraines.
Those who deal with regular or contextual headaches and migraines should also be wary of their caffeine consumption, especially in the hopes that caffeine will alleviate their symptoms. While a study in The Journal of Headache and Pain found that caffeine improved the efficacy of common analgesic medication (such as ibuprofen and acetaminophen), an enormous Norwegian study published in the same journal found that a high-caffeine diet increases the prevalence of headaches.
A study of over 50,000 individuals from the Nord-Trøndelag Health Survey observed that subjects with high caffeine consumption were more likely to experience frequent headaches of more than 14 days per month.
If work stress and other personal circumstances have had you reaching for a coffee more often of late, and you are suffering from headaches, perhaps the cup of Joe is to blame.