Table of ContentsView AllTable of ContentsSleepiness After CoffeeCaffeinated DrinksHow to Feel Awake
Table of ContentsView All
View All
Table of Contents
Sleepiness After Coffee
Caffeinated Drinks
How to Feel Awake
People drink coffee for its ability to increase alertness. However, for some people, coffee makes them more tired. This is likely due to caffeine blocking the receptors of a chemical found in human cells called adenosine. It may also be due to poor sleep habits or the development ofcaffeinetolerance.
This article will discuss why caffeine can make some people sleepy and what to do to optimize the effects ofcaffeine.
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Reasons Coffee Makes Some People Sleepy
Coffeeis a popular morning beverage. Around 85% of the U.S. population drinks at least one caffeinated beverage daily.
For many people, this daily dose of caffeine helps them wake up and stay alert, but for others, it can make them more tired. Below are the reasons why caffeine may make some people sleepy.
Disrupts Nighttime Sleep
Many people drink coffee to wake up and stay awake during the day. Then, when they go to bed, they have difficulty falling asleep. This creates a vicious cycle, in which alack of sleepencourages someone to drink coffee, then makes it difficult for them to sleep.
One-third of Americans typically sleep less than the recommended minimum of seven hours per night.And research shows that caffeine consumption is linked to insomnia.Studies have shown that consuming caffeine even six hours before bedtime can disruptnighttime sleep.
Adenosine Blocker
Adenosineis a crucial part of the sleep/wake cycle. It increases the time that someone is awake and decreases the time that they are asleep.
How coffee makes someone sleepy is that the caffeine in coffee blocks adenosine receptors in the brain, which prevents adenosine from causing sleepiness. Over time, the body increases its sensitivity to adenosine, and once caffeine is metabolized, it can cause excessive tiredness.
Caffeine Tolerance
People who drink coffee or other caffeinated products regularly can develop a tolerance to caffeine. This means that they become used to the effects ofcaffeineand may need more to achieve their desired effects.
Taking in morecaffeineto achieve the desired effects can negatively impact sleep. Ultimately, this leads to tiredness despite drinking coffee.
An Overview of Caffeine Sensitivity
Blood Sugar Effects
A morning coffee may contribute toinsulin resistance(when cells don’t respond well to insulin and can’t take up glucose from the blood, causing the pancreas to produce more insulin).
A 2020 study found that drinking coffee in the morning after a poor night’s sleep increasedglucose intolerance, causing higher than average blood glucose levels. Interestingly, the study also found that a poor night’s sleep without a morning coffee did not reduce glucose tolerance.
The caffeine causes a rise in glucose levels, which will then fall back down. When these glucose levels return to normal, a person may feel tired and have lower energy levels.
Conditions Associated With Fatigue
Sleepy After Coffee But Not Other Caffeinated Drinks
Caffeine and how it affects the body is the underlying reason behind why someone would feel sleepy after drinking coffee.
Other caffeinated drinks—with similarcaffeinecontent—should have the same effects as coffee. However, many caffeinated energy drinks have higher caffeine content than coffee, which may be why someone who is used to the caffeine content of coffee does not feel tired after drinking an energy drink.
An example isenergy drinksrange from 40 milligrams (mg) to 250 mg. Whereas a cup of coffee is approximately 80 mg to 100 mg.
What Can You Do to Feel Awake After Coffee?
Coffee can be a good way to increase morning alertness but cannot cover up long-term poorsleep habits.
Two of the best ways to feel awake after coffee is to make sure you are getting enough sleep and do not drink coffee within six hours ofbedtime.
Summary
Coffee contains a popular stimulant called caffeine that can help some people perk up in the morning. But for others, coffee can make them feel more tired. This may be due to how the caffeine in coffee blocks the chemical receptors for adenosine. It may also be due to caffeine tolerance and poor nighttime sleep.
10 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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