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How Long Does Coffee Keep You Awake? – Does It Affect Your Night Sleep?

People love to drink a cup of coffee or other caffeinated drinks to keep them boosted in the morning, as well as have more energy throughout the day.

If you are one of the people who rely on this drink to stay alert, it is important to understand how long does coffee keep you awake. In reality, each person will wear off the effects differently. Find more details in the sections below!

How Long Does Coffee Keep You Awake?

Well, there is no certain number for this question other than “it depends”. Different people feel the effects of coffee on different levels. The duration of a drug’s effect on someone varies depending on a number of other factors. It can be the way it imbibes, how tired your body is, and what people’s tolerance for it is.

Caffeine has a half-life of 3 – 5 hours, meaning it can stay in your body for up to 5 hours. For example, once you ingest 20 milligrams (mg), half of the amount (10 mg) you have consumed will remain in your system after 5 hours. It can reach the peak level in your bloodstream within 30 to 60 minutes.

This substance works quickly. Most people start to feel more alert within 15 minutes after consuming. These effects will normally last up to six hours. If you drink it daily, the tolerance ability in your body will develop. The reason is that caffeine in such drinks can stop the signal of sleepiness in your nervous system.

How Does Caffeine Work To Keep You Awake?

Several factors impact your brain and body in a cup of Joe. These can be the percentage of caffeine in one pack, the number of cups you drink each day, and how quickly your body metabolizes it.

Out of these factors, it is essential to understand how this substance works, which is the main reason to keep you from overcoming sleepiness.

First of all, why do you feel tired without a cup of coffee? Because there is one substance built up naturally in our body that promotes sleepiness called adenosine. Adenosine is created when your muscles and brain are working actively during the day. The more molecules are released, the more you feel tired and sleepy.

When it goes to the blood, it blocks the way adenosine binds to your adenosine receptors, stopping the feeling of sleepiness. It also delivers serotonin and dopamine to help you feel more energetic and awake.

If it is still working, it will influence your sleep time at night. So, it is better to drink no later than 3 p.m each day to have a good sleep at night.

How Long Can You Keep Yourself Awake By Continuing To Drink Coffee?

As mentioned earlier, each person feels the effects differently. Some people begin to be sensitive to caffeine within a cup of Joe, while others need to drink several of them.

A sufficient dose can keep you alert for up to three days. After that, there are no caffeinated drinks that could do the above trick to your body.

Are There Side Effects To Drinking Coffee To Keep Awake?

Caffeine can lead to sleep of lesser quality and even disrupt your sleep at night. The easiest symbol you could see is that it is hard to fall asleep. One research also concluded that it could pause the timing of your body clock then your total sleeping time will decrease.

So, are there any adverse effects of drinking this liquid to stay awake?

If you consume more doses in a day, it can produce these common side effects:

  • The feeling of sleep or insomnia
  • Nervous
  • Diarrhea
  • Sweating
  • Nausea
  • Heart rate increasing
  • Breathing rate increasing
  • Muscle tremors

But again, human sensitivity to the effects of this substance is variable. Most people do not suffer negative side effects unless they are intake more than four cups a day. Even so, it’s not recommended for you to have such an amount each day.

Always keep in mind that if you are catching up on a few of the above symptoms, try to deduct the daily intake slowly.

How Does Drinking Coffee Affect The Sleep Cycle Long-Term?

Our internal body clocks have two periods of time that affect a one-day cycle of alertness and drowsiness.

Darkness time generates a hormone called melatonin which sends us a signal for sleep. At the same time, bright light delays the production of melatonin that prohibits your going to bedtime.

So, how does this process work in a cup of Joe?

If you consume this drink several hours before bedtime, it will decrease the production of melatonin. This disrupts the natural rhythm in your body. In other words, drinking at night can potentially rearrange the body’s internal clock, establishing insomnia symptoms.

Read more: Why do people like black coffee

What To Do When Too Much Caffeine Disrupts Sleep?

This substance is a helpful drug to stay awake, but consuming too much will cause sleepless nights. If you are staying in this trouble, it is advisable to lower your intake until you get the right amount.

It could be a great help if you practice some yoga or breathing exercises before bed.

Do not forget to set up a healthy sleep schedule by going to bed and waking up at the same time each day. This can help the body to regulate automatically and decrease the need for addictive drugs like caffeine.

What Are Some Caffeine Recommendations?

As with other healthy drugs, you should use them on a daily basis in moderation. To be effective, we have suggested some general instructions for you to follow:

  • Do not consume more than about 300 mg to 400 mg per day. This is approximately three to four cups of coffee.
  • Try to consume a smaller amount if you are pregnant
  • Parents should lower the amount for their children.
  • People who suffer from heart issues or high blood pressure should cut off their levels of caffeine.
  • Try to drink in the earlier hours. Avoid intaking this substance at 3 p.m or before bedtime.
  • It is recommended to stay away from pure powdered caffeine.

FAQs Of How Long Does Coffee Keep You Awake

1. How Much Coffee Is Safe For Adults?

400 mg per day is a recommended amount to keep you healthier. It equals four cups of boiled coffee, 10 cans of coca-cola, or two shots of energy drinks. In fact, the actual content of this substance in beverages is different, especially energy drinks.

2. How Do You Know If Your Coffee Is Causing Sleep Deprivation?

Caffeine is interfering with your sleep and appears in different signs. Worries all night, awakenings frequently, and difficulty falling asleep are common symptoms you could suffer from.

If you are still sleepy during the day with a cup of Joe, this could be a sleep-deprived signal from too much caffeine consumption.

3. What Is Caffeine Withdrawal?

The dependence on it develops quickly in case you drink this beverage on a regular basis. If you cannot get out of bed in the morning without it, you may catch up with a term named caffeine withdrawal.

At that time, your body believes that it needs that particular substance to wake up and make you feel energetic. Without it, your body may go through sweats, chills, and headaches. After that, tiredness, bitterness, muscle pain, and nausea are the next symptoms you could see.

Nevertheless, you can stop your dependence on it after a few days without it. This process takes a lot of power to get through. You may feel uncomfortable in the first place.

4. Can You Really Become Addicted To Coffee?

Yes, people become addicted to this drink and other caffeinated drinks quite quickly. This is due to the chemical changes in your brain. If you consume it regularly, the tolerance to caffeine will increase rapidly the same way with drugs or alcohol.

5. What Are The Foods And Drinks That Contain Caffeine?

Caffeine is usually found in most daily beverages, including:

  • All types of coffee (espressos, lattes, and cappuccinos)
  • Teas (black, green, and white)
  • Soft drinks (coca-cola, sprite, etc)
  • Energy drinks (red bull, monster bang energy, etc)
  • Decaf coffee

You could find caffeine in some kinds of food and medicines, such as:

  • Chocolate and its product (hot cocoa)
  • Ice cream included coffee or mocha ingredients
  • Guarana seeds
  • Protein and energy bars
  • Pre-workout drinks and powders
  • Weight loss pills and headache medicines


After reading our post, you now have information about “how long does coffee keep you awake,” right? There are a lot of factors that play a role in keeping you energetic throughout the day with a cup of Joe.

Its effects typically last for a few hours. If caffeine is keeping you awake, continue to consume it in moderation. If you experience trouble sleeping at night, try to avoid drinking in the afternoon.

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