How Much Caffeine Did I Just Drink?

If you’re reading this, then it’s pretty certain that you, just like 80% of the entire world’s population, drink some form of caffeine every day. Caffeine helps billions of people wake up every morning, or get through a tiring day. It helps athletes perform their best, and it boosts learning for students. It also just makes us feel good, and the ritual of sharing a cup of tea or coffee brings people together, all over the world.

A little bit of caffeine does no harm, but we all know that it’s possible to have too much. To avoid this, it’s important to know how much caffeine is in your drink. The average cup of filter coffee (based on a serving size of 8oz, or 240ml) has around 130 milligrams of caffeine in it — but depending on how you drink your coffee, the amount of caffeine in your cup could be anywhere from 15 to 300 milligrams!

You might also be wondering what caffeine is and whether caffeine is good or bad for your health. Even though most of us drink caffeine every day, not many of us know what caffeine is, or what exactly it does to our bodies. The good news is that caffeine not only makes you feel good — it has some surprising health benefits as well.

In this post, we’ll explain what caffeine is and how it works. We’ll explore the health effects of caffeine and find out how much is too much. And we’ll finish by telling you how much caffeine different drinks contain, so you can work out how much you drink in a day.

If you want to skip ahead to the detailed numbers on each drink, then follow the links below. 

• What is Caffeine and Where Is It Found?
• How Does Caffeine Work?
• Is Caffeine Good or Bad for Your Health? / How Much Caffeine Is Safe to Drink?
• Which Has More Caffeine — Tea or Coffee?
• Which Variety of Coffee Has the Most Caffeine?
• How Much Caffeine Do Different Drinks Contain?
• Table: The Caffeine Content of Different Drinks

What is Caffeine and Where Is It Found?

Caffeine is a naturally occurring compound found in the beans, leaves, and fruits of more than 60 different plants. Most of us get our caffeine from coffee, tea, and cocoa, but there are plenty of other plants with caffeine, such as yerba mate, guarana, or kola nuts.

Plants produce caffeine to protect themselves against being eaten by insects and other animals. It has a bitter taste and is harmful to most insects. For humans, though, caffeine has pleasant effects and is mildly addictive. It’s no wonder we drink so much coffee!

As well as natural caffeine, we also use caffeine that has been purified or even made artificially. Pure caffeine looks like small, white crystals — and it is chemically exactly the same, whether it is natural or made in the laboratory. Pure caffeine is added to soft drinks and is also used in some medications such as cold or allergy medicines, and in some weight loss supplements.

How Does Caffeine Work?

Caffeine stimulates the brain and central nervous system, helping you feel more alert, and reducing the effects of tiredness. It also boosts your mood and improves your reaction time and short-term memory.

It works by blocking a molecule in the brain called adenosine, which the brain uses to signal tiredness. Normally, the amount of adenosine builds up during the day, and the more there is, the more tired you feel. Caffeine blocks the brain from being able to detect adenosine, so it prevents you from feeling so tired.

Caffeine also boosts the levels of other hormones in the brain that lift your mood, and make you more alert and focused.

After you drink caffeine, it works pretty quickly. It reaches your bloodstream within 20 minutes, and the effect peaks about one hour after you drink it. Once the caffeine is in your bloodstream, the liver gets to work on breaking it down right away. It takes about ten hours to clear the caffeine from your system.

Is Caffeine Good or Bad for Your Health?

The Good News

You might be surprised to learn that caffeine has a lot of possible health benefits. Caffeine is proven to be effective against headaches, which is why it turns up in painkillers and other medicines. Caffeine also increases your physical endurance and boosts your metabolism, helping you to burn fat. This is why athletes love it, and why it’s also found in weight loss supplements.

Caffeine has also been linked with many other possible benefits: it seems to help prevent depression, and reduce the risks of some brain diseases such as Alzheimer’s and Parkinson’s disease. It may also reduce the risk of diabetes and heart disease.

Tea and coffee have lots of other health benefits, too — so it’s not always easy to tell which benefits are due to caffeine, and which are due to other compounds in the drink. In any case, there are plenty of good reasons to keep up your caffeine habit!

The Bad News

On the other hand, not all of caffeine’s effects are positive. We all know what too much caffeine feels like: it can make you jittery, anxious, or nauseous — but does drinking too much caffeine do any real damage?

Too much caffeine can cause anxiety, restlessness, tremors, fast or irregular heartbeat, and trouble with sleeping. Most of these negative effects disappear once the caffeine wears off, but it has also been linked with some longer-term effects such as high blood pressure, or heartburn, and can reduce the body’s ability to absorb calcium.

One common misconception is that coffee is dehydrating. Caffeine is a mild diuretic, meaning that it encourages your body to eliminate water. But the water content of the coffee outweighs any diuretic effect.

How Much Caffeine Is Safe to Drink?

Some people are more sensitive to caffeine than others, but for most people, both the US Food and Drug Administration (FDA) and the European Food Safety Authority (EFSA) consider that up to 400 milligrams of caffeine per day is a safe amount. That’s roughly equivalent to drinking four cups of filter coffee per day. It’s important not to drink it all in one go, though! If you have too much caffeine in your body at one time, it becomes harder to break down and the side effects are more severe.

Caffeine can also increase the risk of miscarriage or low birth weight, so for pregnant women, the recommended limit by the EFSA and the American College of Obstetricians and Gynecologists is lower — 200 milligrams per day. That means restricting yourself to around two cups per day, depending on the kind of coffee that you drink.

Which Has More Caffeine — Tea or Coffee?

Tea leaves contain more caffeine by weight than coffee beans. This doesn’t mean that a cup of tea has more caffeine, though! You use a lot more coffee beans to make a cup, so a cup of coffee generally has about twice as much caffeine as a cup of tea. The amount of caffeine in tea varies a lot, but it’s usually around 50 milligrams per cup.

Black tea generally has more caffeine in it than green tea. Other kinds of tea have no caffeine at all — for example, rooibos, or red bush tea, contains no caffeine. Mint tea has no caffeine by itself, but Moroccan mint tea includes green tea as well, so the amount of caffeine depends on the amount of green tea used in the mixture.

Which Variety of Coffee Has the Most Caffeine?

The amount of caffeine varies from one coffee to another, depending on the way that it was grown and processed.

The biggest difference is between Robusta and arabica coffee. Robusta coffee contains about twice as much caffeine as arabica on average, so a traditional blend that includes Robusta will have more caffeine as a result.

Since specialty coffee is only made from arabica coffee, then a cup of specialty coffee will have less caffeine on average. However, there’s no way to say whether a cup of Brazilian coffee or a cup of Colombian coffee has more caffeine, for example. The difference in the caffeine content of individual coffees is much bigger than any difference between countries.

Dark roasted coffee also contains very slightly more caffeine than lightly roasted coffee. Caffeine doesn’t break down much during roasting, but other parts of the bean break down and escape as gasses. In a dark roast, more of the bean has broken down, so the amount of caffeine left behind is larger, compared to the weight of the bean.

However, since the flavor of dark roasted coffee is stronger, a lot of people use less of it to make coffee. A traditional dark-roasted Italian-style espresso, made with 7 grams of coffee, probably has less caffeine than a shot of light-roasted specialty coffee made using 10 grams of coffee — just because more coffee was used to make it.

How Much Caffeine Is in Decaffeinated Coffee?

Decaffeination can’t remove all of the caffeine from coffee, so even decaffeinated coffee has some caffeine in it. Decaffeination typically removes 97–99% of the caffeine from coffee, leaving just a few milligrams per cup behind.The amount of caffeine left in a cup of decaf coffee is less than the amount in a glass of chocolate milk.

Recently, some special low-caffeine varieties of coffee have appeared on the market, such as Laurina or Aramosa. These rare coffees are not decaffeinated but are naturally lower in caffeine because of a genetic mutation. The amount of caffeine they contain varies but typically they have 60–80% less than standard arabica coffee. This means that a cup of coffee made with these varieties might have 30 milligrams of caffeine — less than a cup of tea, but still much more than in decaffeinated coffee.

How Much Caffeine Do Different Drinks Contain?

The amount of caffeine in a coffee ranges from as little as 15 milligrams for a small serving of Qahwa, or Arabic coffee, to 300 milligrams or more for a cup of filter coffee from a chain coffee shop. What makes the difference is not so much how you brew it, but how much coffee you use to make each cup.

The amount of caffeine per cup of Arabic coffee is relatively small, because of the small serving size. A typical serving of Arabic coffee might be just 30 ml, so Arabic coffee contains only 15 milligrams of caffeine per cup. This allows Arabic coffee drinkers to drink many cups of coffee throughout the day, without having too much caffeine.

Turkish-style coffee, meanwhile, is also a small coffee, typically around 60 ml in size. It is around twice as strong as Arabic coffee because it is made with more coffee. Since it is twice as strong and twice as large, a cup of Turkish coffee contains 60 milligrams of caffeine — four times as much caffeine as a cup of Arabic coffee.

Espresso, the strongest coffee of all, contains around 40 milligrams of caffeine per cup. A single espresso is only around 30 ml, so although the coffee is very strong, the total amount of caffeine is not as large as a cup of filtered coffee.

The amount of coffee in an espresso varies a lot depending on how it is made. A single espresso in Starbucks uses more coffee than traditional espresso, so has about 60 milligrams of caffeine per cup. An espresso in a specialty coffee shop might use even more coffee, and thus contain more caffeine — as much as 80 milligrams. Most coffee drinkers drink double espressos — so a latte or Americano made with a double espresso could have anywhere from 80 to 160 milligrams of coffee in it.

At the other end of the scale, a cup of black filter coffee has more caffeine than an espresso, just because it is so much bigger. A 240ml cup of filter coffee will have between 100–150 milligrams of caffeine — but some cafes serve bigger cups than that, even up to 600ml, which can be an enormous amount of caffeine in a single cup.

A cup of Nescafe or other instant coffee, meanwhile, will have around 90 milligrams per 240ml cup. The typical cup size in the home is a bit smaller than that, so the average cup of Nescafe at home has about 60 milligrams per cup.

To summarize, here are the main coffee drinks and the average amount of caffeine they contain. Each cup is assumed to be 240ml or 8oz, except for the espresso, Arabic coffee, and Turkish-style coffee. We also tell you how many cups you can drink before you hit the 400 milligrams per day maximum.

The Caffeine Content of Different Drinks

Armed with this knowledge, you can go and enjoy your next cup of coffee and be sure that you’re drinking a safe amount of caffeine. As long as you make sure that you’re not drinking too much, then caffeine has many health benefits. Go ahead and enjoy the buzz!