The Connection Between Caffeine & Sleep

Many people start their day with a hot cup (or two) of coffee.  The caffeine in coffee can make them feel more alert, less sleepy, more energized, even less moody. Without it, they might be cranky or sluggish.  Some even continue to drink coffee (and other caffeinated drinks such as sodas or energy drinks) throughout the day. But, how are these coffee habits affecting sleep? 

While caffeine is a common tool to promote wakefulness in the morning and to ward off sleepiness during the day, it comes with potential side effects, including jitteriness, headaches, and nervousness. It can also interfere with sleep, especially if consumed too late in the day. Data shows that many people who regularly consume caffeine in the afternoon have also reported at least one sleep problem.

How Does Caffeine Affect Sleep?

Throughout the day, our bodies produce a chemical called adenosine, a sleep-promoting chemical that is produced in the brain during waking hours. Normally, adenosine builds up in the brain the longer we’re awake; the longer we’re awake, the more adenosine we have and the sleepier we become.

Unfortunately for coffee drinkers, caffeine blocks adenosine receptors and their sleep-inducing effects. In other words, we’re wide awake. Our wired, overstimulated brains make it difficult to fall asleep or stay asleep at night. As a result, our overnight sleep quality suffers and we wake up tired the next day — looking for more coffee to compensate and starting the cycle all over again.

Can Caffeine Cause Insomnia?

When consumed in large amounts or close to bedtime, caffeine can disrupt the natural sleep-wake cycle, making it difficult to get a restful night’s sleep. It’s generally recommended to avoid consuming caffeine in the hours leading up to bedtime to minimize the risk of insomnia and to promote better sleep quality.

People who have chronic insomnia may use caffeine to cope with the daytime effects of sleep deprivation. However, this practice may worsen the symptoms of insomnia at night. The adverse effects of caffeine on insomnia symptoms can be more severe in people who only use caffeine occasionally compared with those who use it every day.

How Long Does Caffeine Keep You Awake?

Caffeine is known to boost cognitive functions, such as memory and attention, especially in sleep-deprived people. However, it cannot ward off all of the long-term sleep loss. Even though caffeine can marginally improve performance, it’s no substitute for a restful, restorative night of sleep. And, especially if consumed too late in the day, the alertness-promoting effects of caffeine can linger into the evening and interfere with sleep. 

The effects of consuming caffeine typically begin after around 30 minutes and may last up to five hours or longer.  Whether caffeine effectively keeps you awake when you are sleepy and how long caffeine makes you feel alert varies depending on various factors, including how much caffeine you’ve consumed, how frequently you consume caffeine, and even your genetic makeup.

Does Caffeine Make Some People Sleepy?

For some people, yes!  There are a few different reasons why some people feel that caffeine makes them tired instead of more alert:

• The disruptive effects of regular caffeine use on sleep can create a vicious cycle. Caffeine use can make sleep deprivation worse, and sleep loss causes sleepiness the next day, which in turn causes an increased need to consume more caffeine in order to cope. Ongoing sleep deprivation can cause a level of daytime sleepiness that even caffeine cannot counteract.

• Caffeine tolerance is another possible reason for feeling tired after consuming caffeine. Research studies looking at the effects of caffeine tolerance have produced mixed results, but some caffeine consumers recognize that consuming caffeine daily can dampen its alertness-promoting effects and lead to dependence over time.

• Sleepiness can also be a symptom of withdrawal from caffeine, which is why regular caffeine users may feel sleepy in the morning until they consume it.

How Much Caffeine Is Safe To Drink?

The Food and Drug Administration (FDA) indicates that it’s generally safe for adults to consume up to 400mg of caffeine per day. Since there can be a lot of variation in the way people respond to and metabolize caffeine, some people may be able to safely consume more, while others may need to limit themselves to less. The best way to get an individualized recommendation on caffeine intake for your specific situation is to speak with a doctor. 

Caffeine is most often consumed in drinks. Since there are so many different caffeinated products, it can be hard to know exactly how much caffeine is in a particular drink, especially a fresh-brewed cup of tea or coffee that has no label.

How Many Hours Before Bedtime Should You Have Caffeine?

The generally recommended cut-off time for caffeine use is a minimum of eight hours before bedtime. For example, if you typically go to bed at 10 p.m., avoiding caffeine after 2 p.m. may help minimize sleep problems. 

If you’re struggling with sleep, start keeping track of the time of day you consume caffeine and how you sleep that night. You may find that you sleep better with a longer period of caffeine abstinence before bed, such as 10 hours or more.

How Can You Tell if Caffeine Is Affecting Your Sleep?

Difficulty falling and staying asleep, nausea, headaches, or nervousness could all be signs of caffeine overuse or dependence. If you find yourself feeling excessively sleepy during the day and caffeine is not helping, this could be a symptom of a sleep disorder or an underlying medical issue. Schedule a conversation with your healthcare provider to discuss your sleep concerns and how caffeine and other factors may be affecting you.   

If you decide to reduce your caffeine intake or stop using caffeine altogether, it may help to taper down gradually to reduce the risk of withdrawal effects like headache, anxiety, and poor mood.

How Else Can You Stay Alert During the Day?

There are many energy-boosting alternatives to caffeine:

• Get morning light exposure: Your body’s internal clock responds to light as a cue to wake up and increase alertness. Turning on bright lights, or, better yet, going outside for natural light lets your body know it is time to start your day. 

• Practice healthy sleep habits: Setting a consistent sleep schedule and arranging a relaxing sleep environment are examples of sleep hygiene approaches that can improve your sleep and reduce your reliance on caffeine. 

• Exercise: Exercising can improve your and may help you sleep better as well. 

• Take a power nap: Napping is not a substitute for high-quality nighttime sleep, but a short nap of up to 20 minutes can temporarily restore your energy if you are feeling sleepy. 

The best rule of thumb when it comes to caffeine: Limit your consumption, both in quantity and timing.  You don’t necessarily have to give up your morning coffee, but it may be wise to cut back on it if you rely on it to make up for poor sleep.  There’s no substitute for getting a good, quality night’s sleep.

Do you feel your sleep issues go beyond caffeine consumption?  Visit our Sleep Study page to learn more about how we can help.

Source: https://www.sleepfoundation.org

Source: https://ahs.atlantichealth.org