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Home » How Much Coffee is Too Much? The Truth About Caffeine in Coffee

How Much Coffee is Too Much? The Truth about Caffeine May Surprise You

How much coffee is too much coffee? Is there such a thing as too much coffee? Look – there are several undeniable health benefits linked to daily coffee consumption, and every day it seems scientists gather more hard evidence to strengthen the case.

a word or two about the Benefits

On average, if you drink the following cups of coffee (black, no milk, no cream, no sugar) per day you’ll also benefit from:

  • 35% lower risk of developing type 2 diabetes from 6 to 7 cups.
  • 20% lower risk of being hospitalized for arrhythmia or strokes from 1 to 3 cups.
  • Decreased risk of developing Parkinson’s disease (stats not available).
  • Decreased risk of developing cirrhosis and also liver cancer (stats not available).
  • 65% lower risk of developing dementia and also Alzheimer’s disease from 3 to 5 cups.

The evidence is overwhelming, so let’s raise our mugs and drink up to the magical fountain of caffeinated youth, right? Right? Well, you just hang on to that thought, because a critical question arises here: Is there such a thing as a caffeine overdose?

How much coffee is too much coffee? See, there are many factors involved, and this also varies from person to person, but we’ll walk you through absolutely all the details.

The Basics of Coffee & Caffeine

First things first: caffeine comes from coffee beans and other sources like berries and nuts. Caffeine is the substance in your cup of joe that wakes you up.

In this article, it’s also important that you understand that when we refer to coffee, we are talking about regular, black coffee. This means NO milk, or cream, or sugar.

A standard cup of coffee has roughly two calories, approximately 80-100mg of caffeine, and packs a powerful source of antioxidants that will get you covered for your daily needs whether it’s caffeinated or decaf, the benefits are the same.

Related: What is caffeine made of?

Caffeine Sensitivity and Caffeine Tolerance.

We all react very differently to the substances we consume, and coffee is no different. This is because our unique genetic makeups and the genes responsible for metabolizing caffeine do it through our livers.​

All existing variations give room to something known as caffeine sensitivity, and there are three large groups:

Hyper-sensitive: People in this group get reactive to small amounts of caffeine, sometimes a cup or less will cause them insomnia, accelerated heartbeat, and jitters. Also worthy of note, all of the health benefits mentioned above, are not established as true for people under this category.

Normal: The vast majority of the population lies under this group. They can usually take up to 400mg of caffeine daily without showing any side effects. All of the studies made about the caffeine benefits are proven right for people with normal sensitivity.​

Hypo-sensitivity: Roughly 1 out of 10 people are born hypo-sensitive to caffeine, which means they can take massive doses (sometimes more than 600mg per day) and not show any side effects at all. People in this group might not experience the same health benefits from drinking the recommended amount of coffee per day.

After reading the above groups, can you take a guess at which one you fall under?

 2 cups of coffee and beans on the table - how much coffee too much

On the other hand, we have caffeine tolerance, and this happens when your body slowly generates a natural resistance to the effects of caffeine, as opposed to the first time you had it.

Caffeine tolerance can develop in as early as one day, or take up to four. You can also reset your caffeine tolerance level by detoxing your body completely from it — tapering off your consumption for several weeks (1).

However, our bodies have simple detoxing protocols for all foreign substances, and they do it now and then, so you don’t have to worry about this.

Simply put, regular coffee drinkers have a higher tolerance for caffeine. So do people with a higher metabolism rate, and women in general when compared to men, unless they are taking contraceptive pills, in which case their tolerance level is up to 33% slower than females who are not on the pill (2).

To help guide you on how much caffeinated drink you can consume, here’s our very own caffeine intake calculator.

Caffeine Concentration in Certain Types of Coffee

Remember how we stated earlier that a regular cup of black coffee has roughly 80-100 mg of caffeine? Well, now that you can consider yourself some sort of coffee guru, how about we go a little deeper?

cup of coffee with spoon

Let’s analyze the amount of caffeine found in the following 8 oz (240 ml) samples, measured consistently over time. After all, plain black coffee can’t be everyone’s vice:

  • 3-12mg for decaffeinated.
  • 27-173mg for instantaneous.
  • 102-200mg for plain and brewed.
  • 240-720mg for espresso.

Notice the limits? Unlike caffeine pills that have a fixed amount of caffeine per dosage, coffee drinks have varying caffeine content. Maybe you’re wondering why the heck there such is a broad range in the first place? Well, the caffeine molecule is a natural occurrence in around 60 different types of plants.

The biological evolution of a certain plant, combined with environmental conditions, and even the brewing method used, all play a role in the amount of caffeine a sample will have. Also different types of coffee beans will have different levels of caffeine, such as:

  • 1.13% for Ethiopian.
  • 1.42% for Tanzanian.
  • 1.5% for Arabica.
  • 2.4% for Robusta.

Safe Amounts of Caffeine Intake

Safe amounts of caffeine
DISCLAIMER: we are coffee fanatics – not doctors. Please consult with a medical professional before going on a wild coffee binge based on the above figures. More on our disclaimer here.

While it would be almost impossible to set an accurate amount of caffeine that would be safe for absolutely everyone (for all the reasons stated above). According to Mayo Clinic, it looks somewhat like this:

Up to 400 milligrams (mg) of caffeine a day appears to be safe for most healthy adults. That’s roughly the amount of caffeine in four cups of brewed coffee, 10 cans of cola or two “energy shot” drinks. – Mayo Clinic

Here is a consensus for most of the general population:

  • 400mg or less for healthy adults.
  • 300mg or less for pregnant women.
  • 0mg for children from 0 to 4 years old.
  • 2.5mg or less for every kilogram of body weight for children from 4 to 12 years old.
  • 200mg or less for people who suffer from arrhythmia, hypertension or type 2 diabetes.

The bottom line is: coffee has way more positive effects on our overall health than negative ones. The evidence gathered can’t be argued with and if you get yourself the time to analyze exactly how your body reacts to caffeine, and adhere to the safe amounts recommended (about 4 to 5 cups daily for adults), you will be just fine.

Not only that, you will benefit hugely from it, in the long run, because a regular intake of caffeine WILL improve your overall quality of life.


  • Because coffee’s boosting effect usually takes about 30 minutes to act, you should take your cup of coffee right before your 26-minute power nap (yes, scientists figured out exactly how much you should nap for optimal results). Try it out, and your energy level will go Beast-Mode to help you out on those never-ending office days. Works with coffee from a good espresso machine, or any other highly caffeinated brews.
  • Do you love the smell of freshly made coffee in the morning, but can’t finish one cup without feeling jittery? Try lower caffeine types of coffee, like instant (god forbid) or Ethiopian beans.
  • Time to go to bed but you get a craving for a Cup of Joe? Go decaf. While technically still caffeinated, for a coffee to be considered decaf it must have 97% of its total caffeine removed. Hard to argue with that. And you will still get a good night’s sleep.

Next time someone asks “how much coffee is too much?” you’ll know exactly what to tell them, without taking a wild guess. For more coffee-related goodness, start on our homepage.

Frequently Asked Questions

It depends on the type of coffee, your health, and your weight. Generally, healthy adults can consume up to 400mg of caffeine daily. So, to determine how many cups of servings of coffee you can drink, you need to know how much a caffeinated beverage contains. For example, a 16-oz (475 ml) serving of Starbucks cold brew contains 200mg of caffeine (3). This means that a healthy adult can drink as much as 2 servings of this beverage daily. Meanwhile, caffeine in soda is around 46 mg per can, which means you can drink as much as 4 to 5 cans per day before you reach the limit. Learn how much caffeine is in each type of coffee.

If you consumed a lot more caffeine than recommended amount, you may experience unpleasant side effects such as irritability, diminished quality of sleep, and jitteriness. In severe cases, caffeine overdose can cause tummy ache, headache, irregular heartbeat, vomiting, and/or even seizures. Constant consumption of highly-caffeinated drinks may also cause hormonal imbalance (4). 

The lethal dose of coffee is 150mg per kilogram of your body (5), which means that a 70-kg man can die if he consumes 10,500mg of caffeine or 11 to 15 cups of highly-caffeinated drinks like Death Wish Coffee in a single day! That’s a lot of coffee!

  1. Romm, C. (2016, July 28). Here’s How to Undo a Caffeine Tolerance. Retrieved from https://www.thecut.com/2016/07/heres-how-to-undo-a-caffeine-tolerance.html
  2. Hall, A., & Hall, A. (2017, December 07). 7 Reasons You’re So Sensitive To Caffeine. Retrieved from https://www.huffpost.com/entry/varying-effects-of-caffeine_n_6671788
  3. Caffeine Informer. (n.d.). Starbucks Cold Brew Coffee. Retrieved from https://www.caffeineinformer.com/caffeine-content/starbucks-cold-brew
  4. Pietrangelo, A., & Cherney, K. (2017, August 7). The Effects of Caffeine on Your Body. Retrieved from https://www.healthline.com/health/caffeine-effects-on-body
  5. ASAPScience. (2014, August 28). Your Brain on Coffee. Retrieved From https://youtu.be/4YOwEqGykDM
Jovana D
I come from a country where people drink domestic coffee (what the rest of the world knows as Turkish coffee) and where Nescafe designates all instant coffees ever made. So, imagine my first encounter with, say, Hario V60...Yes, it was love at first sight.  Today I’m a moderate coffee connoisseur and a huge coffee lover. My favorite brewing methods are the V60 and traditional espresso-making. Yet, despite my country’s long tradition of Turkish-coffee-adoring, I somehow cannot stand it. That’s just too dark, even for me.