How to Know if Caffeine is Preventing Quality Sleep

If you struggle with sleep and can’t find the culprit, you may want to look in your coffee mug. Your caffeine habits could be interfering with your sleep.

How to know if caffeine is disrupting your sleep quality

Most adults can enjoy a cup or two of coffee or tea safely, and some even find they’re more productive after a boost of caffeine. 


Caffeine is a stimulant that tricks your brain into thinking you’re not tired. It can help you get a jump on the day and is purported to have many health benefits to offer. 


But as with most things in life, there’s never just one side to the story. 


Understanding how caffeine works and what it does to your body can help you decide if coffee is compromising your sleep quality, and uncover whether or not your daily cup o’ joe is helping or hurting your body’s ability to get a solid night of rest.


Here’s what you need to know to decide if caffeine is contributing to your sleep problems:

(Sneaky) Sources of Caffeine

We all know that consuming caffeine too late in the day can keep you up at night. But just because you take a pass on the late afternoon coffee run, doesn’t mean you haven’t invited caffeine into your system by some other means. 


Caffeine likes to hide out where you least expect it: Here are a few places you’ll find caffeine outside of your morning coffee cup:


  • Decaffeinated coffee—decaf is really a misnomer. Even decaf coffee contains trace amounts of caffeine. 
  • Chocolate—yep. That chocolate mousse dessert you just enjoyed after dinner might be keeping you awake! Remember that hot chocolate and other treats are also likely to contain caffeine. Look out for chocolate puddings, breakfast cereals, and other treats that might be keeping you awake.
  • Energy drinks & Colas—it’s not surprising that most energy drinks and colas contain caffeine. What’s surprising is the amount of caffeine some drinks contain. One 8oz Redline energy drink contains 316mg of caffeine, which is 
  • Medications—some headache remedies and PMS medications contain as much as 60mg of caffeine. Read the label and make sure you aren’t accidentally ingesting caffeine too close to bedtime.

Know Your Serving Size

Depending on whether you buy your coffee from a coffee shop or brew your own at home, your serving size will differ. Caffeine’s power is measured in milligrams (mg), and a standard 8oz cup of coffee has around 95mg of caffeine per cup. That means if you’re stopping by Starbucks on your way to work and guzzling down a 20oz Venti coffee, your actually drinking almost 3 whole cups of coffee, and close to 300mg of caffeine.


The Mayo Clinic claims that while the caffeine content of each individual drink may vary, up to 400mg of caffeine per day should be safe for a healthy adult. 

Side Effects of Too Much Caffeine

Caffeine is a stimulant and affects the body as much as it does the brain. Moving beyond the 400mg recommended daily allowance for caffeine can have some negative effects on the body. If you go overboard with the caffeine you’ll probably notice some physical symptoms. 


Here are a few of the telltale signs you’ve had too much caffeine:

  • Migraine
  • Insomnia
  • Nervousness
  • Dizziness
  • Excessive thirst
  • Fever
  • Irritability
  • Diarrhea
  • Increased heart rate

Some People Are Sensitive to Caffeine

It’s important to note that some people are more sensitive to caffeine than others. How well you tolerate caffeine and the effect it has on your brain and body depend on your individual genetic tolerance and how well your liver processes caffeine. If your body metabolizes caffeine quickly and your central nervous system tolerates caffeine well, you’ll likely be able to consume more of it without affecting your sleep. If your liver metabolizes more slowly and you have a genetic makeup that is more sensitive to the effects of caffeine, your system will be more likely to suffer from lack of sleep after even moderate amounts of caffeine.


Caffeine affects each person differently, so you are truly the only person who can decide if it’s having a negative impact on your sleep. Being aware of how your body feels under the influence of caffeine and Knowing when and how to drink your coffee will help you to enjoy your favorite brew without disturbing your sleep.