Caffeine is, by far, the most used psychoactive drug on Earth. Yet, because of its widespread use and acceptance, people often fail to consider whether caffeine and mental health influence one another.

Not all caffeine use is bad. In fact, there are several positive benefits of caffeine, but certain people will experience fewer mental health symptoms if they cut down on caffeine.

Caffeine Use in the United States

In a study from 2014, researchers found that 85% of the United States population drinks a caffeinated beverage every single day. On average, this accounted for 165 mg of caffeine per day for everyone who drank some type of caffeine.

Adults between the ages of 50 and 64 drank significantly more caffeine at around 226 mg per day, with the 90th percentile drinking 380 mg per day.

The United States isn’t alone in its caffeine consumption. Worldwide, about 80% of the population consumes caffeine every day, with an even higher average of 200 mg of caffeine per day.

Common Sources of Caffeine

Caffeine is available in many forms. Most often, it is consumed as a beverage, such as coffee or tea. Each type of caffeinated beverage contains a different amount of caffeine, and the same type of beverage can often have varying levels of caffeine content.

Some of the most common caffeinated beverages and their caffeine content include:

  • Coffee: 96 mg in an 8 oz. serving
  • Espresso: 64 mg in a 1 oz. serving
  • Soda: 22 mg in an 8 oz. serving
  • Black Tea: 47 mg in an 8 oz. serving
  • Green Tea: 28 mg in an 8 oz. serving
  • Energy Drinks: 71.9 mg in an 8 oz. serving

In addition to beverages, caffeine can often be found in several supplements. It is a common ingredient in pre-workout blends, in its pure powdered form as a capsule, or in many common “energy” supplements.

Caffeine is also a common ingredient in many migraine medications, such as Excedrin or its generic varieties. Recognizing the different sources of caffeine is important if you’re aiming to stay below the daily suggested limit, which can significantly reduce your risk of mental health consequences of caffeine use.

Recommended Limits of Caffeine

The Food and Drug Administration suggests that healthy adults consume no more than 400 milligrams of caffeine each day. Using the caffeine content of common caffeinated beverages outlined above, this translates to roughly four cups of coffee, six shots of espresso, or five servings of an energy drink.

Serving size matters. A typical energy drink can is 16 ounces, meaning each can contains over 140 mg of caffeine on average. And while a one-ounce serving of espresso has just 64 mg of caffeine, a latte or cappuccino at your local coffee shop can contain two or three ounces of espresso per drink.

Similarly, some energy drinks may have substantially more caffeine than the average. And if you brew your own coffee, using more than the standard amount of coffee beans can similarly drive the caffeine content skyward.

These are important considerations when looking at caffeine and mental health, as the effects of caffeine on the brain can quickly escalate with higher dosages.

How Caffeine Interacts With the Brain

Caffeine belongs to a class of drugs known as central nervous system stimulants. Broadly, this means that it increases activity in the brain. Caffeine accomplishes this task by blocking the adenosine receptor, which, in turn, promotes wakefulness and a sense of energy.

Adenosine is a chemical produced constantly in the body. It is the waste product of a chemical known as ATP, which is used to produce energy throughout the body. When adenosine binds to its receptor sites throughout the brain and body, it creates a feeling of tiredness and fatigue.

But when people drink caffeine, adenosine is unable to latch on to these receptor sites. Essentially, caffeine blocks your body from feelings of tiredness, which makes people feel more alert and awake.

But adenosine isn’t the only way caffeine produces its stimulating effects. It also increases the level of cortisol and adrenaline inside of the brain. Cortisol is commonly referred to as the stress hormone, whereas adrenaline is a neurotransmitter that is triggered during the “fight-or-flight” response.

Taken altogether, these effects of caffeine all contribute to both its perceived benefits and many of the negative mental health effects of caffeine consumption.

Mental Health Effects of Caffeine

Research on caffeine and mental health has been ongoing for decades. It has uncovered countless mental health impacts of caffeine, ranging from large negative mental health effects to mild positive effects and everything in between.

While the body of evidence on caffeine’s effects on mental health is vast, it is often contradictory too. Seemingly, every couple of weeks, a new study shows that caffeine is either helpful or harmful.

Sifting through this data for the most reliable, evidence-based effects isn’t always easy, but the main, consistent findings are outlined below.

Impaired Sleep Quality

Perhaps the most dramatic and obvious effect of caffeine on your mental health is caffeine’s ability to negatively affect your sleep. Since caffeine blocks your body from receiving the fatigue signal from adenosine receptors, people who consume large amounts of caffeine often have trouble falling asleep or staying asleep at night.

If you’ve ever drank an energy drink or put on a pot of coffee in the late hours, you may have experienced this effect — your body feels fatigued, and your motivation is low, but you don’t feel tired. If you try to lie down and go to bed, you may spend hours tossing and turning before finally falling asleep.

Lack of sleep can lead to a number of serious mental health side effects. Getting consistent, high-quality sleep plays an important role in regulating mood, aiding with concentration, and having you feel your best mentally.

When this cycle of healthy sleep is interrupted by caffeine, you can quickly start to feel worn down and experience ever-growing mental health symptoms.

Thankfully, the solution to this problem is relatively simple and doesn’t have to mean quitting caffeine altogether.

Caffeine has a half-life of about four to six hours, which means that 50% of caffeine is eliminated from the body in this amount of time. This means that if you drink a caffeinated beverage at 4 p.m., your body still has half of the caffeine content of the beverage in your bloodstream between 8 p.m. and 10 p.m.

Restricting your caffeine intake to the morning hours — meaning not drinking any caffeine past noon — can dramatically reduce the impact caffeine has on your sleep.

Increased Anxiety

As a central nervous system stimulant, caffeine increases the level of adrenaline and cortisol within the brain. For many people, these small boosts are what produce the spike in energy and focus. However, for people prone to anxiety, this can trigger panic attacks or anxious symptoms.

These spikes in anxiety can occur whether someone has a diagnosed anxiety disorder or not. Research has shown that even moderate caffeine usage can significantly increase the risk of anxiety symptoms, but the risk of anxiety becomes much higher when people consume more than 400 mg of caffeine in a single day.

If you’re a regular caffeine drinker and have been experiencing symptoms of anxiety, cutting back on your caffeine intake might be a good idea.

Caffeine Withdrawal

If you are a habitual caffeine drinker, you may experience several symptoms of caffeine withdrawal if you skip your coffee or tea in the morning. Caffeine withdrawal can have a number of both physical and mental health effects, including:

  • Headache or migraine
  • A feeling of fatigue
  • Irritability
  • Difficulty concentrating
  • Depressed mood

For most people, caffeine withdrawal occurs about 12–24 hours after the last dose of caffeine consumed. If no more caffeine is taken, the symptoms of caffeine withdrawal begin to get worse and peak around 48 hours after your last caffeinated beverage, but they can continue for up to nine days.

Since the effects of caffeine withdrawal can start in less than a day, many habitual caffeine consumers can experience the symptoms of mild withdrawal on a daily basis.

If you wake up feeling groggy every morning, have difficulty concentrating, or are irritable to your friends and family before your first cup of coffee, it might be a sign of caffeine withdrawal.

Positive Effects Between Caffeine and Mental Health

Of course, not all of the effects of caffeine on mental health are negative. There have been several studies showing that moderate caffeine usage can have beneficial effects such as:

  • Mood boost
  • Increased focus
  • Greater productivity
  • Faster reaction times

But while there is an astounding amount of evidence that supports the positive benefits of caffeine consumption, there are significant caveats that need to be considered.

First, most of these studies examine the effects of caffeine on people who aren’t habitual caffeine consumers. People who rarely drink coffee will experience a much greater sense of elevated mood and focus than those who drink several cups a day.

Second, many studies that look at habitual caffeine consumers specifically often compare their performance after caffeine consumption to their performance before caffeine consumption. That is, performance is compared against people who are currently experiencing caffeine withdrawal.

If you rarely drink caffeine, you can likely experience a number of positive mental health benefits. But if you consume caffeine every day, the perceived benefits you experience are much more likely to be the result of alleviating caffeine withdrawal rather than a boost over what you would experience if you never drank caffeine at all.

Should You Stop Drinking Caffeine?

Knowing the many potential side effects of caffeine and mental health, you may be wondering if it’s time to quit drinking caffeine once and for all. The answer, as is often the case, is that it depends.

If you’re experiencing significant anxiety symptoms or sleep disruption, caffeine is a likely culprit. Similarly, if you’re experiencing regular symptoms of caffeine withdrawal that you wish to get rid of, quitting caffeine for good may be the best solution.

But if you’re not experiencing these side effects, and you simply enjoy your morning cup of coffee, you don’t necessarily need to cut out caffeine for good. In moderation, caffeine can be an enjoyable and healthy part of your daily routine.

Finally, if you’ve tried cutting out caffeine but are still struggling with mental health symptoms that interfere with your daily life, you may want to consider seeking professional mental health treatment. Working with a therapist or mental health professional is the most reliable method of overcoming serious mental health concerns.

Get a free consultation with Plus by APN by calling 424.644.6486 or by filling out our online contact form. Our comprehensive mental health treatment options can help get you back on track to living a life free from mental health struggles.


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