If you have a hard time functioning in the morning without coffee, you're not alone.
In fact, caffeine is considered the most commonly used drug in the world (1).
Many people see coffee drinking, and the caffeine intake that goes with it, as one of the few socially acceptable addictions.
However, some are wary of putting coffee or caffeine in the same category as stronger addictions.
This article takes a critical look at both sides of the coin to determine whether caffeine truly is addictive.
Coffee contains caffeine, a natural stimulant also found in smaller amounts in tea, chocolate and soft drinks.
It is currently the most commonly consumed psychoactive substance, and the one to blame for coffee's potentially addictive properties (2).
The amount of caffeine found in coffee varies greatly. For instance, some cups of coffee can contain as little as 30 mg, whereas others hold over 300 mg.
However, on average, an 8-ounce cup of coffee contains around 100 mg of caffeine — enough to produce noticeable effects for most people.
Once consumed, caffeine takes about 30–60 minutes to reach its maximal concentration in the blood. Effects tend to last between three and nine hours, depending on the person (3).
Summary: Coffee contains caffeine, a natural stimulant that is responsible for coffee's addictive properties.
When you consume caffeine, it's quickly absorbed by your gut before traveling to your brain (5).
Once there, it has a direct stimulating effect on your brain cells.
This allows caffeine to fit into adenosine receptors in the brain, blocking them and preventing adenosine from binding to them to produce feelings of tiredness.
In turn, the blocked receptors stimulate the release of other natural stimulants and allow some of them, such as dopamine, to work more effectively. This further increases alertness and reduces feelings of tiredness (1, 5).
Put simply, caffeine works in two ways:
- It prevents your brain cells from signaling that you're tired.
- It causes your body to release other natural stimulants and boosts their effects.
The end result of caffeine's effect on the brain is feelings of alertness, well-being, concentration, self-confidence, sociability and motivation to work (4).
Summary: Caffeine acts as a stimulant on the brain, reducing fatigue, increasing alertness and enhancing concentration.
Just as with other addictive substances, caffeine may become physically addictive.
That's because regular, sustained caffeine consumption can lead to changes in the chemistry of your brain.
For instance, your brain cells may start to produce more adenosine receptors as a way to compensate for the ones blocked by caffeine (1).
In turn, the higher amount of receptors requires you to consume a higher amount of caffeine to achieve the same "caffeine fix." This explains how regular coffee drinkers build up a tolerance over time.
On the other hand, abruptly cutting off the caffeine supply suddenly leaves your brain with a lot of free receptors for adenosine to bind to.
This can produce strong feelings of tiredness and is thought to be the main reason behind the caffeine withdrawal symptoms that often arise from going cold turkey (1).
While daily caffeine consumption creates a physical addiction, the act of regularly drinking coffee may promote a behavioral addiction (1).
Unlike physical addiction, behavioral addiction may not be caused by the caffeine intake itself.
Rather, the social environment in which coffee is consumed and the feelings that accompany its consumption are what may encourage you to have another cup.
That said, it's unclear how large a role this behavioral aspect plays in caffeine addiction. More research is needed (9).
Summary: Caffeine can become addictive through changes it causes in your brain. Additionally, drinking coffee often produces positive feelings, which encourage you to repeat the behavior.
As is the case with other substances, the risk of becoming addicted to coffee depends on various factors.
For one, experts believe that your likelihood of getting hooked may be influenced, in part, by your genetics (1).
Naturally, regular coffee drinkers have an increased risk of undergoing the brain changes previously described and becoming dependent on caffeine.
For the moment, what remains unclear is how long it takes for your body and brain to physically adapt to daily caffeine intake.
What experts do know is that withdrawal symptoms such as headaches, lack of concentration, drowsiness and irritability can appear as little as 12–24 hours after your last caffeine dose, and can last up to nine days (10).
In addition, they can result from reducing your daily caffeine dose by as little as 100 mg — the equivalent of one cup of coffee per day (10).
The good news is that the severity of symptoms usually peaks within the first two days and goes down gradually thereafter (10).
Summary: Regular caffeine consumption is needed to stimulate the physical adaptations consistent with addiction. However, it's currently unclear how long it takes for these changes to occur.
Arguably, addictions may vary in strength. That said, most share clinically meaningful symptoms, including:
- A persistent desire or unsuccessful efforts to cut down or control use
- Continued use despite harm
- Characteristic withdrawal symptoms
These symptoms are often used by clinicians to diagnose an addiction, and a recent review reports that a good proportion of caffeine users develop them (11).
However, despite this, many experts are wary of officially labeling caffeine as an addictive substance.
In fact, a recent survey of addiction professionals reveals that only 58% believe that people can develop a dependence on caffeine. Several reasons are cited in support of this view (12).
First, addictive substances such as amphetamines, cocaine and nicotine are thought to stimulate the area of the brain linked to reward, motivation and addiction to a higher extent than caffeine does (9).
In addition, for most people, regular caffeine consumption poses little harm to themselves and society, which is less often the case with illegal drug use.
What's more, most consumers do not struggle to control their caffeine intake like many do with other addictive substances.
That's because high doses of caffeine produce unpleasant sensations, such as trembling and jitteriness. This tends to discourage people from consuming more, rendering caffeine intake self-limiting (9).
When it comes to caffeine withdrawal, symptoms do not last as long and tend to be much milder than those linked to stronger addictions. They also generally do not require professional intervention or medication (12).
Due to these differences, some experts are concerned that officially labeling habitual caffeine use as an "addiction" may make addiction to other substances — for instance, illegal drugs — appear less severe.
Currently, the American Psychiatric Association (APA) recognizes caffeine withdrawal as a clinical condition, but has yet to classify caffeine addiction as a substance abuse disorder.
However, the APA agrees that the topic warrants further study and even proposes potential diagnostic criteria to be used for research (1).
On the other hand, the World Health Organization (WHO) does officially recognize caffeine dependence as a syndrome (1).
Summary: Caffeine users can develop dependence, but symptoms are generally considered milder than those linked to stronger substances.
Unlike most other addictive substances, coffee and caffeine consumption can have certain health benefits.
The most well-researched include:
- Improved brain function: Regularly drinking coffee may improve alertness, short-term recall and reaction time. It may also reduce the risk of Alzheimer's and Parkinson's diseases (13, 14).
- Improved mood: Studies show that regular coffee or caffeine consumers have a lower risk of depression and suicide (15, 16).
- Boosts your metabolism: Daily caffeine consumption may increase your metabolism by up to 11% and fat burning by up to 13% (17, 18, 19).
- Enhances exercise performance: Caffeine can increase tolerance to fatigue, improve exercise performance and make your workouts feel easier (20, 21, 22).
- Protects against heart disease and diabetes: Regularly drinking caffeinated beverages like coffee and tea may reduce the risk of heart disease and type 2 diabetes in some individuals (23, 24).
Summary: Unlike most other addictive substances, coffee and caffeine provide some health benefits. However, it's best to limit your intake to 400 mg of caffeine, or about 2–4 cups of coffee per day.
Despite these benefits, it's worth mentioning that too much caffeine per day may do more harm than good.
In addition, certain individuals should completely avoid caffeine or limit their intake to smaller amounts.
Moreover, if you're taking the muscle relaxant Zanaflex or the antidepressant Luvox, consider avoiding caffeine. These drugs can increase its effects (13).
Summary: Pregnant women and those who metabolize caffeine slowly may want to limit coffee and other caffeine-rich foods. Individuals suffering from certain medical conditions may also want to limit their intake.
Coffee and caffeine have addictive properties that may lead to dependence.
However, the risk of addiction is affected by many factors and can vary from person to person.
That said, if your current caffeine use is not causing you any harm, there's probably little to worry about.