Caffeine In Coffee - Good or Bad For Health?

by | Oct 18, 2018 | General

An espresso generally has lower caffeine content, about 50 mg per shot, while a cup of drip coffee easily contains as much as 200 mg of caffeine. This indicates that there is plenty of variation.

An average coffee cup usually contains around 90 to 100 mg of caffeine.

is the recommended limit of caffeine /mg/ in a day

In the absence of strict guidelines and lab tests, it is quite tricky to determine the level of caffeine in different types of coffees. This makes it even more difficult to keep your caffeine consumption under the recommended limit of 300 mg in a day.

Average caffeine in various types of coffee

200 mgs135 mgs110 mgs50 mgs8 mgs
brewed coffeefilter coffeeinstant coffeeEspressoDecaf coffee
Brewed CoffeeFilter CoffeeInstant CoffeeEspresso CupDecaf Coffee

There are several factors that can have an impact on the level of caffeine in a coffee cup. Perhaps, the most distinctive among these factors is the roast intensity; however, there are a number of other important factors to take into account.

Caffeine content tends to vary between species and types of coffee beans and may depend on the location where coffee beans are grown, the method by which coffee is roasted and how it is prepared. All these different factors lead to variations in the level of caffeine between cups of coffee.

According to the Mayo Clinic, even the same kind of coffee bought from the same shop may vary considerably in the level of caffeine from one day to the next. In case the coffee beans were ground in a different manner, or an additional scoop was poured in the coffee machine, it can lead to a significant fluctuation in the caffeine content.

Whether you are looking for low or high caffeine levels, bear in mind that these factors can make a difference.

Dark Roast vs. Light Roast

coffee roast

When choosing whether to go for dark or light roast coffee, plenty of people tend to opt for the deeper and bolder flavor of dark roast coffee as they often believe that it contains more caffeine.

However, this is not true.

In fact, light roast coffee contains a much higher concentration of caffeine due to the fact that coffee beans themselves are the primary source of caffeine. The longer you roast the coffee beans, the more caffeine you will end up losing.

This is one coffee myth that definitely needs to be debunked.


Arabica and Robusta Coffee Beans

The level of caffeine in a typical cup of coffee may fluctuate considerably based on the kind of coffee beans used. Robusta and Arabica are the two most commonly used coffee beans. Arabica beans are typically used in most coffee houses and are often considered premium quality.

On the other hand, Robusta beans are often used in packaged coffee products and have a lower quality compared to Arabica beans. Robusta beans have a higher level of caffeine concentration compared to Arabica beans; however, the brewing and roasting process can affect the level of caffeine.

Instant vs. Brewed

Brewed Coffee Instant Coffee

Instant coffee has lower caffeine concentration as it has evolved into a swift dissolve formula. A cup of coffee, on average, has around 150 mg of caffeine when made using the drip method.

However, when percolated, an average coffee cup contains about 80mg. In contrast, instant coffee usually contains 100 mg of caffeine in each cup, on average.

Brewing Methods

Brewing Methods

Another factor that can have a direct impact on the caffeine content in coffee is the kind of brewing method used in the preparation of coffee. There are various different methods that can be used to prepare coffee. Some of them are regular brewing, French press, drip coffee, and espresso.

The general rule is that the longer the coffee stays in the brewing process, the higher the level of caffeine it will have. For example, if you prepare French press coffee, depending on your preference, the coffee can stay for a long or short interval of time in the brewing process before you pull the plunger.

The longer the coffee stays in the brewing process, the higher the level of caffeine accumulation. Even in the case of espresso, you can experience fluctuation in the level of caffeine as you can brew espresso for a long or short period of time.

Serving Size

Serving size also affects your caffeine consumption. To figure out the exact amount of caffeine you are taking in a cup of coffee, you should know the size of your coffee cup.

Most coffee shops are known for their notoriously large cup sizes. These can easily go as high as 25 oz. The quantity of coffee in these large cups is equivalent to nearly 3 to 4 standard-sized coffee cups and this leads to a much higher caffeine intake.

Top 10 Benefits of Caffeine

  • Caffeine increases memory
  • Caffeine can speed up metabolism
  • Caffeine detoxes the liver
  • Caffeine protects the skin
  • Caffeine helps those with asthma
  • Caffeine can stimulate hair growth
  • Caffeine helps ward off Alzheimer’s
  • Caffeine reduces kidney stone risk
  • Caffeine is good for the heart
  • Caffeine protects against Parkinson’s disease

Top 10 Side Effects of Caffeine

  • Caffeine content raises blood pressure for up to three hours
  • Caffeine Contributes to Insomnia
  • Caffeine reduces insulin sensitivity
  • Caffeine withdrawal can cause headaches, anxiety, irritability, lack of focus, fatigue, digestive issues
  • Caffeine can even make you feel shaky
  • Caffeine harms eye health
  • Caffeine could reduce fertility in women
  • Caffeine Increases cholesterol
  • Caffeine may cause blood clots
  • Caffeine overdose can be life-threatening

Caffeine Levels in Commercial Brands

A number of commercial coffee brands often contain greater caffeine content compared to regular or home-brewed coffee.


StarbucksThis brand is easily the most famous coffee chain in the world and has probably the most caffeinated coffee drinks on the market. The levels of caffeine in brewed coffee available at Starbucks are as follows:

  • Short: 180 mg
  • Tall: 260 mg
  • Grande: 330 mg
  • Venti: 415 mg

Moreover, a single espresso shot at Starbucks has about 70 mg of caffeine. Therefore, all small cups of espresso-based coffee drinks contain 70 mg of caffeine. Some of these drinks include lattes, macchiatos, cappuccinos, and Americanos. Decaffeinated coffee from Starbucks has about 15 to 30 mg of caffeine, depending on the size of the cup.

Dunkin Donuts

Dunkin' Donuts

This is another popular coffee chain that operates throughout the worldwide. The levels of caffeine in their brewed coffee are given below:

  • Small: 215 mg
  • Medium: 302 mg
  • Large: 431 mg
  • Extra large: 517 mg

A single shot of espresso at Dunkin Donut contains about 75 mg of caffeine, and you can expect the same amount in their several espresso-based drinks. Decaffeinated coffee at Dunkin Donuts also contains some caffeine. According to a number of sources, a small coffee cup contains 53 mg of caffeine, while a large coffee cup has about 128 mg. This is almost the same level of caffeine as will you find in different types of regular coffee.


McDonald’s also offers coffee worldwide, under its McCafe brand. Although it is the biggest fast-food chain that also sells coffee, they don’t calculate or standardize the quantity of caffeine their coffee contains. According to estimates, the levels of caffeine in their brewed coffee drink are as follows:

  • Small: 109 mg
  • Medium: 145 mg
  • Large: 180 mg

The espresso drinks at McDonald’s has 70 mg of caffeine in each serving, and their decaf coffee contains about 8 to 14 mg, depending on the cup size.

Caffeine Infographic

CoffeeCorner Caffeine Infographic

Caffeine Infographic created by CoffeeCorner

Caffeine Facts

  • Caffeine was first discovered in 1819 in Germany.
  • The word “caffeine” is from the German Kaffe (“coffee”).
  • Caffeine is an alkaloid occurring naturally in some 60 plant species, of which cocoa beans, kola nuts, tea leaves and coffee beans.
  • Caffeine is the world’s most widely consumed psychoactive drug.
  • 90% of adults consume caffeine in some form.
  • Pure caffeine is a bitter, highly toxic white powder.
  • The USA imports more than 15 million pounds of powdered caffeine annually.
  • Decaf coffee is not completely caffeine-free; it still has up to 15 mg of caffeine.
  • The lethal dose of caffeine for humans is 150 mg per kilogram of a person’s body weight per day.
  • Pregnant and breastfeeding women are advised to limit their caffeine intake to 200mg per day.
  • Women metabolize caffeine about 25% faster than men.
  • Light roast coffee contains a much higher concentration of caffeine.
  • Instant coffee has a lower caffeine concentration.
  • The longer the coffee stays in the brewing process, the higher the level of caffeine is.
  • Coffee typically has three times more caffeine than tea or cola.
  • Energy drinks have less caffeine than coffee.
  • Caffeine is not addictive by accepted definitions and according to most authorities.
  • Caffeine kicks in after 20 minutes and lasts 8–14 hours.
  • The half-life of caffeine in your body is about 4 hours.
  • Smokers metabolize caffeine at a rate of 50% faster than nonsmokers.

Top 10 occupations with the heaviest caffeine drinkers

  1. Scientists/lab technicians
  2. Marketing/PR professionals
  3. Education administrators
  4. Editors/writers
  5. Healthcare administrator
  6. Physicians
  7. Food preparers
  8. Professors
  9. Social workers
  10. Financial professionals



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  1. Sadiq Zucker

    There are pleasures in life which transcend discussions of benefits and drawbacks. One of these pleasures is hot coffee upon rising.

  2. Clement Wong

    But I wonder if different origins of coffee beans do have difference in Caffeine level too ?
    If most American Coffees come from South and Central America, my experience is that they give a stronger kick and I felt a bit jittery after consumption…feels different ! When I drink a South East Asian bean Coffee, like from Vietnam, Arabicas, there’s less kick from them, even their robusta doesnt give me a kick as high as say, the Colombian Arabica, and still less than an Indian Colabar ( Monsoon Robusta) espresso which notably raised my heartbeat ! Can someone do some testing, compare caffeine levels amongst coffee origins ? Many thanks.
    I am 65 years old, and used to work in the coffee industry.


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