Can caffeine cause insomnia?

Can caffeine cause insomnia?

What is caffeine?

Caffeine is a drug naturally occurring in many coffee and tea plants, which stimulates our central nervous system, increasing alertness and attention. Caffeine is considered the world’s most widely consumed psychoactive drug.  

Because of its mainstream popularity and social acceptability, it is one of the least regulated psychoactive substances in the world. The US Food and Drug Administration recognizes the drug as generally safe, and classifies a toxic dose as over 10 grams a day for adults, with an average cup of coffee containing between around 80-180 mg of caffeine. On an average day, approximately 85% of Americans consume some kind of caffeine.


Where does caffeine come from?

The bitter substance can be found in more than 60 plants, such as coffee beans, tea leaves, tree bark, kola nuts used in sodas, and cacao pods which we use to make chocolate. Synthetic caffeine can also be found in a number of medicines, drinks, foods, and snacks.


How does caffeine affect our bodies?

Caffeine affects our bodies and brains to help us feel alert and awake by blocking sleep-promoting receptors, called adenosine receptors. Adenosine is a very important organic compound that helps regulate our sleep-wake cycles; when adenosine is able to bind to the receptors in our brains, we feel more tired and our neural activity is slowed, encouraging us to get the rest we need. 

Caffeine stimulates our metabolism in a number of ways. The drug excites our central nervous system making us feel more awake, acts as a diuretic encouraging urination to remove excess water and salt in our bodies, increases our stomach acid levels, and increases our blood pressure. Caffeine typically affects our bodies for four to six hours, on average, with many feeling the lasting effects for more.


What are the side effects of excessive caffeine consumption?

Consuming too much caffeine (around 400 mg in a day) can lead to a number of health concerns, including insomnia, headaches, dizziness, dehydration, anxiety, restlessness, and dependency. High doses can also cause sweating, nausea, increased heart rate and breathing rate, diarrhea, and muscle tremors. Withdrawal from caffeine after periods of extended use can lead to headaches, sleepiness, bad moods, and lower energy levels.


How long does caffeine keep you up?

Caffeine consumed at night can cause challenges to our sleep cycles as it blocks our ability to feel tired. While it can lead to increased cognitive function, it is no match for a restorative, full night of sleep! 

The half-life of caffeine, or the time it takes for the drug to decrease or disintegrate by half, is between four and six hours according to the FDA. This long-lasting effect of caffeine can be responsible for keeping us awake for much longer depending on your metabolism however. Other factors that affect caffeine’s impact include how much caffeine is already in your system, and the actual caffeine content in your beverage, medication, or food. 

Can caffeine cause insomnia?

The stimulant can affect our sleep in a number of ways; causing trouble getting to bed, and impacting our quality of sleep itself. Caffeine, blocking our adenosine receptors, makes it hard for us to feel tired and more challenging to drift off to sleep. If you’ve ever laid wide awake in bed and remembered that late night cup of coffee or tea, you’re probably all too familiar with this side effect. 

Caffeine can also prevent us from sleeping deeper, and be responsible for more sleep interruptions. Additionally, because caffeine is a diuretic, it can cause you to wake up more frequently, sending you to the bathroom for your bladder. 

Older people may also be more sensitive to caffeine and its lasting effects on sleep. Additionally, nicotine users (those who consume tobacco, or vape nicotine) can typically metabolize caffeine faster than those who don’t. 


How can you tell if caffeine is disrupting your sleep?

While insomnia and other sleep disorders are incredibly common among adults, it is very possible that caffeine intake is preventing you from getting deeper sleep. Insomnia, headaches, and anxiety are all common signs and symptoms of caffeine dependence and overuse. 


How can you reduce caffeine’s interference, and improve your quality of sleep?

Because caffeine can interrupt our ability to fall asleep, stay asleep, and sleep deeper, it’s best to limit intake to early in the day, and only a few cups or doses as needed.

There are a number of ways to improve your sleep habits and hygiene, including setting a sleep schedule, establishing nightly routines, making changes to your daily habits and lifestyle, and setting up your bedroom environment for the best sleep possible. Learn more about ways to improve your sleep hygiene from our blog.