Have you ever wondered how much caffeine in a cup of coffee? Well, coffee is one of the most popular drinks in the world and it can give us a boost in the morning.
But do you know how much caffeine is too much for you or coffee is good for you? If you want to know how much caffeine in a cup of coffee and the most caffeinated coffee?
Then keep reading this blog to know the answers of all these questions.
What Is Caffeine?
Coffee is one of the biggest sources of caffeine. How much caffeine in a cup of coffee depends on several factors, such as the brewing method, brand, and type.
Caffeine is a natural stimulant that is found in many nuts, seeds, and leaves, and it is native to South America and Africa.
Coffee is well known as the source of caffeine, but caffeine is also present in cocoa and tea. Caffeine blocks the adenosine that makes you feel tired and help to relax the brain.
Caffeine takes an hour to reach its full effect. According to the Dietary Guidelines For Americans 2015-2020, in the United States, 95 percent of adults are consuming drinks and foods that contain caffeine.
On average, American adults consume between 110 and 250 mg of caffeine daily. The amount varies between different coffee drinks that range from almost zero to over 500 mg.
The Food and Drug Administration estimates that a typical 8-ounce cup of coffee contains around 80-100 of caffeine.
What Are The Factors Affecting Caffeine Content?
How much caffeine in a cup of coffee depends on many factors such as:
1. Type Of Coffee Beans:
There are so many factors that affect how much caffeine content in a cup of coffee. So, one of the main factors is the type of coffee beans.
There are many varieties of coffee beans available, that may naturally contain different amounts of caffeine.
But the most popular two spices of plants that produce coffee beans are coffee arabica which is known as Arabica and coffee canephora which is known as Robusta.
Most of the coffees are made up of either Robusta, Arabica, or a mixture of these two types of beans. So the coffee brand can play a role in your caffeine intake.
For example, Arabica beans contain half the caffeine of Robusta beans. The higher dose of caffeine may seem like a good thing, so it makes the taste of Robusta beans acidic and unpleasantly bitter.
You can also find the robusta beans in espresso-like coffee or the coffee blends that claim to be the best strongest coffees.
According to one study, researchers had found that arabica beans contain 34.1-38.5 g caffeine per kg of dry coffee, and the robusta beans contain 68.6-81.6 g caffeine per kg of dry coffee.
How much caffeine in a cup of coffee depends on coffee roasting. Lighter roasts have more caffeine than darker roasts, so although the darker roasts coffee beans have a deeper flavor.
The type of roost you choose depends on you, whether it is light, medium, or dark. Because it can influence the amount of caffeine that goes into the cup of coffee.
Many people believe that dark roasting coffee contains more caffeine because they are stronger in flavor. However, the darker roasting coffee is generally lower in caffeine levels as compared to the lighter roasts.
Because the prolonged heat of heavier roasting can break down the caffeine molecule. Some of the people also like to put roasting burns off the caffeine.
If you want less caffeine in your cup then go with the dark roast coffee because the dark color means dark roast and less caffeine in a big cup of coffee.
3. Type Of Coffee:
How much caffeine in a cup of coffee also depends on the type of coffee. Because the caffeine content varies significantly different between regular brewed coffee, decaf coffee, espresso, and instant coffee.
If you also prefer to drink coffee from a cafe as compared to making it at home. Then the commercial brand type that you choose may influence how many mg of caffeine in coffee.
(Also read: Benefits Of Coffee Face Pack For Healthy And Glowing Skin)
4. Serving Size:
The serving size can also affect how much caffeine in a cup of coffee.
Because one cup of coffee can range anywhere from 30-700 ml, so it greatly affects the amount of caffeine content.
5. Brewing Methods:
The way coffee is made can also affect caffeine content. When you make your coffee at home then it depends on how strong you make the coffee.
If you like a stronger coffee taste or flavor and you brew the coffee for longer periods of time. Then there may be a higher amount of caffeine in a coffee as long it takes you to brew it.
The water ratio in the coffee is also very important as well as the serving size of a coffee mug.
How Caffeine Works?
When you consume the caffeine it quickly absorbs from gout to the bloodstream. From the bloodstream, it travels to the liver and breaks down into the compounds that affect the function of various organs.
The main effects of caffeine are on the brain. It functions by blocking the effect of adenosine, which makes you feel tired, and neurotransmitter that relaxes the brain.
Normally, the adenosine levels build up over the day and make you increasingly more tired and you feel sleepy.
So consuming caffeine can help you to stay awake by connecting the adenosine receptors in the brain without activating them.
This blocks the effects of the adenosine that leads to reduce tiredness. It may also increase blood adrenaline levels and increase the brain activity of the norepinephrine and neurotransmitters dopamine.
This combination further stimulates the brain and also promotes the state of arousal, focus, and alertness. Because caffeine can affect the brain, caffeine is also referred to as a psychoactive drug.
Additionally, caffeine is effects to quickly. The amount of caffeine that in one cup of coffee can take as little as 20 minutes to reach your bloodstream. It will take about 1 hour to reach full effectiveness.
How Much Caffeine In A Cup Of Coffee?
Different types of coffees contain varying amounts of caffeine. So, how much caffeine in a cup of coffee depends on the type of coffee that you like to drink.
Here are some most common types of coffee below:
1. Brewed Coffee
Brewed coffee is the most common way that most of the US and European people are using to prepare. The brewed coffee is also a collard filter coffee or regular coffee.
It is made by pouring hot or boiling water over the ground coffee beans and it usually contained in a filter. This mixture can usually sit in a metal, paper, or plastic filter that separates the grounds from the brewed coffee.
People make the brewed coffee in various ways like using a filter, french press, or a percolator. Have you wondered how much caffeine does 8 oz of coffee have?
An 8-oz coffee cup typically contains around 95 mg of caffeine. There are also different techniques in brewing coffee that affects the caffeine content in the final cup these are:
- French press
- Filter or drip coffee
- Percolating vacuum brewing
- Greek or Turkish
- Concentrate brewing
The caffeine content varies also follows:
- Percolated: 64- 272 mg of caffeine in coffee
- French press: 80 – 135 mg of caffeine in coffee
- Boiled (Turkish or greek): 160- 240 mg of caffeine in coffee
- Drip or filter: 115 – 1175 mg of caffeine in coffee
Espresso is the most popular type of coffee worldwide. It is known for the heavily caffeinated drink.
Espresso is made by forcing the hot water or the steam through the very fine coffee grounds and producing a thick, richly flavored liquid with a layer of foam, or the cream on top.
For making the espresso coffee involves the use of a machine or stovetop moka pot.
One serving of pure espresso can measure just two fluids once, but the many espresso drinks like flat whites, Americano, lattes, and macchiatos are combined with the shot or two of the espresso with other ingredients like hot water, foam, steamed milk, chocolate, and whipped cream.
The average shot of espresso contains approximately 150 mg of caffeine. This is the same caffeine content as an eight-ounce cup of pour-over coffee.
The one shot of espresso contains caffeine as one eight-ounce cup of brewed coffee.
But if you prefer to buy coffee from a coffee shop like Starbucks, then the cup of brewed coffee contains more caffeine than one shot of espresso.
In that sense, the serving of espresso contains less caffeine than a serving of regular coffee. In terms of caffeine per ounce, espresso coffee contains more caffeine.
One ounce of average espresso contains 75 mg of caffeine, while one ounce of an average drip of coffee contains only 18 mg of coffee.
If you drink an eight-ounce cup of full or pure espresso then you consume 600 mg of caffeine, which is equal to the caffeine in just over four cups of pour-over coffee.
3. Espresso-Based Drinks
Many popular coffee drinks are made with espresso shots by mixing the varying types and amounts of milk. These include Americanos, cappuccinos, lattes.
The milk does not contain any additional caffeine, so these drinks contain the same amount of caffeine as the straight espresso.
The single small espresso shot contains about 63 mg of caffeine, while the double or large contains 125 mg of caffeine.
4. Instant Coffee
Instant coffee is made from brewed coffee that freezes dried or sprays dried. It is generally in the large, dry pieces that dissolve in water.
To prepare this instant coffee, you need to simply mix one or two teaspoons of dried coffee with the hot water. But it does not need any brewing.
Instant coffee contains less caffeine than the regular coffee, with one cup contain roughly 30-90 mg caffeine.
5. Decaf Coffee
Although the name may be deceiving, decaf coffee does not mean that it is entirely caffeine-free.
It may contain varying amounts of caffeine, it contains approximately 0-7 mg per cup, with the average cup of coffee containers 3-milligram caffeine.
While some varieties contain higher amounts of caffeine that depends on the type of coffee, cup size, and the method of decaffeination.
6. How Much Caffeine In A Cup Of Coffee In Cold-brew
Cold-brew coffees are different from ice coffee. It simply contains serving brewed coffee over ice.
For making cold brew coffee, just manufacturers steep the coffee grounds in the water at the room temperature for anywhere between 8 and 24 hours.
According to the one study, 12- oz cups of cold brew coffee contains between 153 mg and 238 mg of caffeine.
7. How Much Caffeine In A Cup Of Coffee In Decaf Iced Coffee
The amount of caffeine in the decaf iced coffee is not always the same as the amount of caffeine in the hot coffee.
Well, regular iced coffee is exactly the same as the hot coffee, but it pours over ice.
The ice that pours over the coffee takes up space in your cup which means a sixteen-ounce cup full of iced coffee doesn’t have much caffeine.
While a sixteen-ounce cup of hot coffee contains about 290 mg of caffeine. Whereas the sixteen-ounce cup of iced coffee contains about 203 mg of caffeine because about 30% of caffeine is taken up by ice.
The cold brew coffee is just as heavily caffeine contained hot coffee, it uses an entirely different brewing process than iced coffee. Cold brew coffee is made by steeping coffee grounds in cold water for at least twelve hours.
The water ratio in cold water is usually a little over double as compared to hot coffee, which means that more caffeine is extracted into the finished product.
This higher caffeine content in cold brew makes up for the space taken up by the sweetener, milk, and ice that dilutes the regular iced coffee.
How Many Mg Of Caffeine In Coffee Brands?
With the help of the above list, you can make a safe assumption that an 8-oz cup of brewed coffee contains 95 mg of caffeine.
One shot of espresso or an espresso-based drink contains about 63 mg and the caffeine content in the decaf coffee is about 3 mg.
The caffeine content in popular coffee brands are usually higher than the home-brewed drinks.
Additionally, the many coffee shops make coffee servings in rather larger cup sizes that range is up to 24 oz.
The amount of coffee in these serving cups is about 3- 5 times more amount than a regular size cup of coffee. Here are some example of popular brands are:
1. How Much Caffeine In A Cup Of Coffee Of Starbucks
The people who prefer to buy their coffee, then the amount of caffeine per brand also varies because of the different factors.
Some brands offer more caffeine than the homemade brewed coffees, like Starbucks. Starbucks is the most famous coffee brand in the world.
This famous shop can list the caffeine content of their coffee products along with the other nutritional information in their drink menu.
How much caffeine in a cup of coffee in Starbucks? Here is the caffeine content of brewed coffee at Starbucks is as follows:
- Short: 180 mg
- Tall: 260 mg
- Grande: 330 mg
- Venti: 415 mg
The one shot of espresso at Starbucks contains 75 mg of caffeine. All small espresso-based drinks also contain 75 mg of the caffeine of coffee.
The caffeine content of a tall cup of some Starbucks beverages as follows:
- Pike place roast: 235 mg
- Decaf pike place roast: 20 mg
- Caramel macchiato: 75 mg
- Cappuccino: 75 mg
- Cold-brew with col foam: 155 mg
The larger size of the cup is made with the two or even three espresso shots, so likewise it contains 150 or 225 mg of caffeine.
Decaf coffee from Starbucks contains approx 15-30 mg of caffeine it also depends on cup size.
2. How Much Caffeine In A Cup Of Coffee In Dunkin’ Donuts
Dunkin Donuts is a popular coffee and donut retailer shop that offers a wide range of caffeinated beverages.
How much caffeine in a cup of coffee from dunkin’ donuts.
According to caffeine informer, the caffeine in a medium cup of some of the coffee drinks which offered at Dunkin’ Donuts is the following:
- Decaf brewed coffee: 10 mg
- Latte: 119 mg
- Brewed coffee: 210 mg
- Americano: 249 mg
- Cold-brew: 260 mg
- Espresso coffee contains 85 mg per single shot.
3. How Much Caffeine In A Cup Of Coffee In McDonald’s
McDonald’s is one of the popular brands that sell coffee all over the world under its brand.
It is one of the biggest fast-food chains which sells coffee all over the world. But McDonald’s does not calculate or standardize the amount of caffeine in their coffee.
As estimates the caffeine content of their brewed coffee is about the:
- Small: 109 mg
- Medium: 145 mg
- Large: 180 mg
The espresso coffee contains approx 71 mg per servings and decaf contains 8- 14 mg, it also depends on the size of the cup.
4. How Much Caffeine In A Cup Of Coffee Of Seattle’s Best
People find Seattle’s best coffee products at the company’s retail stores and drive-thrus as well as some fast-food restaurants, such as the burger king and Subway.
According to the caffeine informer, the small cup of Seattle’s best coffee products contains the following amount of caffeine:
- Latte: 75 mg
- Mocha: 80 mg
- Brewed coffee: 260 mg
Seattle’s best espresso contains approx 75 mg of caffeine per single shot.
Some Other Source of Caffeine
We all know that the most popular source of caffeine is coffee, but many other foods and beverages also contain caffeine.
But the FDA do not require manufacturers to list the quantity of caffeine on their packages of beverages, dietary, and food supplements.
Here are the other common sources of caffeine below:
1. How Much Caffeine In A Cup Of Tea
Tea contains varying quantities of caffeine, but the amount of caffeine in tea is typically less than a similar size cup of coffee. An 8-ounce cup of tea contains a variable amount of caffeine.
How much caffeine in a cup of tea also depends on how long you steep it and the type of tea whether white, green, or its black tea. Black tea contains about 40 mg of caffeine.
Black tea decaf contains about 2 to 10 mg of caffeine. Green tea contains about 20 mg of caffeine. White tea contains about 15 mg of caffeine.
While herbal tea contains 0 caffeine, but not all the herbal teas are caffeine-free so check the box.
If you want to reduce the level of caffeine from tea, just steep for five minutes and throw out the liquid then re-steep the tea bag in freshwater. This will help you to remove almost all caffeine from the tea.
2. Soft Drinks
Soft drinks, such as fruit-flavored beverages and sodas also contain caffeine.
For example, 12-ounce sodas contain lots of calories and varying amounts of caffeine from 54 mg in Mountain Dew to 34 mg in coke to 0 mg in 7-Up.
Even cream soda and root beer contain caffeine.
3. Energy Drinks
Energy drinks also contain a high level of sugar and caffeine. The caffeine that is present in the energy drinks is either synthetic or it from natural sources, such as guarana leaves.
The amount of caffeine that is present in energy drinks varies significantly between brands. According to the FDA, the amount of caffeine in these beverages typically ranges from 40 to 250 mg per 8 oz.
Brands of energy drink also contain 316 mg of caffeine per 8 oz of coffee. So you should consume these carefully because of the high amount of caffeine.
Chocolate naturally contains caffeine, but the amount varies according to the cacao content of the chocolate. Dark chocolate is good for the heart but it contains a high amount of caffeine. Only one ounce contains 20 mg of caffeine, while the same amount of milk chocolate contains about 6 mg of caffeine.
While an 8-ounce carton of milk chocolate gives you calcium, but you can also get a heavy dose of caffeine and sugar.
So, be sure to pay attention to the caffeine in all chocolate desserts too.
5. Coffee-Flavored Desserts
If you like to include 8 ounces of your favorite coffee frozen yogurt or similar products, then do it early in the day.
This may be made with real coffee and an average of 85 mg of caffeine.
Some of the OTC and the prescription medication contains caffeine that helps to enhance pain relief.
For example, the Menstrual Relief Maximum Strength is a combination of 60 mg of caffeine, 15 mg pyrilamine, and 500 mg acetaminophen.
How Many Mg Caffeine In Coffee Recommended Daily Intake?
The Dietary Guidelines For Americans 2015-2020 recommends that adults consume no more than 400 mg of caffeine per day.
But there are no set guidelines for children, according to the American Academy of Pediatrics discourage children and adolescents from consuming caffeine.
One review suggests that adolescents aged 12-18 years of age should consume less than 100 mg of caffeine per day.
They also warn that caffeine may have a stronger effect on under 12 years of age children because they tend to weigh less.
While younger children can tolerate an average of 2.5 mg of caffeine per 1 kg of their body weight.
How Much Caffeine Is In Cappuccino?
Most of the coffee-based drinks such as cappuccino, mocha, latte, and macchiato are all made by using espresso shots. They mixed with a variety of different and varying amounts of milk.
As we know that milk does not contain any additional caffeine, So these drinks contain approx the same amount of caffeine as the straight espresso shot contains.
While if you choose a single shot then the drink would contain about 63 mg caffeine coffee and a double shot of this drink will contain around 125 mg caffeine.
Most Caffeinated Coffee
Who is the most caffeinated coffee, the answer to this straightforward question is, it includes many factors.
These factors can help you to determine what type of coffee is the most caffeinated coffee. These factors also affect how much caffeine in a cup of coffee.
So, let’s have a look at these factors:
1. Brand And Cup Size Of Coffee
Buying coffee from commercial brands can affect the amount of caffeine that you get in your coffee. Because every brand has a different standard amount of caffeine and varying cup sizes.
The places such as fast-food chains have a large cup size of coffee, that can hold the 3 or 4 size cup of regular coffee.
This will increase the caffeine intake, well most of the people drink the entire cup of coffee and consider it as one cup of coffee.
But the reality is a lot more than that. Some commercial brands also have high caffeine coffee as compared to the coffee that you make at home.
2. How Much Caffeine In A Cup Of Coffee Depends On Beverage Type
You can also find out the most caffeinated coffee in terms of the type of coffee that you prefer to drink. As I mentioned above the 8 oz brewed coffee contains 70-114 mg of caffeine.
That means it has about 9 to 10 mg per ounce. In terms of having more caffeine per ounce then the espresso is more caffeinated coffee.
The one shot of espresso contains about 60-80 mg of caffeine coffee. Which is nearly about 40-55 mg per ounce. If you order a double shot of espresso so you can get as much caffeine.
How Much Caffeine In A Cup Of Coffee Is Good For You?
Coffee is containing high antioxidants properties that are good for health. But having too much caffeine can link you to the adverse side effects like:
- Sleep disruption
- Heart Palpitations
- Fast heart rate
- Upset stomach
Consuming 400- 600 mg caffeine in a cup of coffee per day does not cause any adverse side effects in most people.
Because it is about 6mg/kg of body weight or 4 – 6 an average cup of coffee per day.
But caffeine affects every person very differently. Some people are very sensitive to the coffee while others find a large amount of caffeine doesn’t affect them.
Well, this is largely due to genetic differences. You just need to experiment on you and find out what amount of caffeine is suits you the best.
What Are The Health Benefits Of Caffeine
1. Improve Mood And Brain Function
Caffeine contains the ability to block the brain-signaling molecule adenosine. This causes a relative increase in other signaling molecules, such as norepinephrine. Which benefits boost your mood and brain function.
According to one review, drinking 37.5-450 mg of caffeine can improve alertness, reaction time, and short-term recall.
Some study says that drinking 2-3 cups of caffeinated coffee per day that provide you about 200- 300 mg caffeine can help to lower the 45% risk of suicide.
Drinking coffee also lowers the 13% risk of depression. But when it comes to mood improvement more caffeine is not necessarily better.
Also, the second cup cannot provide the caffeine benefits unless if you consume them at least 8 hours later after the first cup of coffee.
Drinking between nearly 3-5 cups of coffee per day or more than 3 cups of tea per day can also reduce the 28-60% risk of brain diseases such as Parkinson’s and Alzheimer’s.
Because coffee and tea contain other bioactive compounds that are also beneficial for health.
(Also read: Super Foods That Improve Memory And Brainpower)
2. Boost Metabolism
Caffeine can boost metabolism and help you to lose weight. Because it contains the ability to stimulate the central nervous system so the caffeine may increase metabolism and burn fat.
Consuming 300 mg of caffeine per day can help you to burn an extra 79 calories per day. Also eating a low-calorie diet or 1000 calorie diet can help to lose weight fast
Well, this amount seems small, but it is similar to the calorie excess which is responsible for the average yearly weight gain of 2.2 pounds in Americans.
(Also read: Ignite Metabolism and Lose Weight Naturally)
3. How Much Caffeine In A Cup Of Coffee Can Enhance Exercise Performance
When it comes to exercise performance caffeine can increase the use of fat in the body. This is beneficial for the exercise performance because it can help the glucose to store in muscles last longer.
So, it will be delaying the time that takes your muscles to reach the exhaustion. Consuming caffeine can also improve muscle contractions and increase the tolerance of fatigue.
Researchers have found that doses of 2.4 mg per pound of body weight can improve the endurance performance up to 5 % when you consume caffeine 1 hour before the exercise.
One report has similar benefits of caffeine in the team sport, resistance exercise, and high-intensity workout.
Caffeine may also reduce the perceived exertion during the exercise by up to 5.6% that can make the workouts easier.
4. Make Your Heart Healthy And Reduce Diabetes
Caffeinated beverages like tea and coffee help to reduce the risk of heart disease and type 2 diabetes, but this may depend on the individual.
Yes, you heard the right, caffeine does not raise the risk of heart disease. Consuming caffeine can lower the 16-18% risk of heart disease in men and women, who are drinking between 1-4 cups of coffee daily.
Drinking 2- 4 cups of coffee or green tea per day can lower the 14-20% risk of stroke. But caffeine slightly increases the blood pressure in some people.
Well, this effect is generally small and tends to fade for most individuals when they consume regular coffee. Drinking coffee or caffeinated beverages also help to protect against diabetes.
According to the one review, the people who drink the most coffee have a 29% lower risk of developing type 2 diabetes.
So similarly people who consume the most caffeine have a 30% lower risk of type 2 diabetes. Because the risk drops by the 12-14% on every 200 mg of caffeine that they consume.
While consuming decaffeinated coffee link to a 20% lower risk of diabetes. All these factors indicate that the beneficial compounds of coffee can also help to protect you from type 2 diabetes.
(Also read: How To Control Diabetes Naturally)
Some Other Health Benefits Of Coffee
- Liver protection
- Decreased cancer risk
- Gout Prevention
- Healthy gut
- Skin protection
- Reduce MS risk
- Eyelid spasm
- Mouth, throat, and other cancers
Side-effects Of Caffeine
Studies suggest that drinking more than 300 mg a day of caffeine, or the amount equal to the three cups of coffee, lead to the:
- Pregnancy loss
- Delayed the growth of fetal
- Abnormal fetal heart rhythm
According to the NIH, the weeks before the pregnancy are also counted in this.
Researchers say that, if both parents consume more than the two caffeinated drinks a day before a week they conceive may face the loss of pregnancy more likely.
So women should limit their caffeine intake to 200mg or less during their pregnancy.
2. How Much Caffeine In A Cup Of Coffee Cause Depression
Well, we know that caffeine increases alertness by blocking the effects of adenosine. But consuming high caffeine intake may worsen the symptoms of depression and anxiety.
According to the Diagnostic and Statistical Manual of Mental Disorders published by the American Psychiatric Association caffeine can induce anxiety disorder is one of four caffeine-related syndromes.
According to 2016 found that, in 234 middle students in Korea, the higher caffeine intake was linked to a higher weight than lower academic achievement and a higher risk of severe depression.
But this theory is unclear, whether the caffeine leads to depression or depression can cause people to consume more caffeine.
(Also read: Healthy Foods That Help To Fight Depression
3. High Blood Pressure
Caffeine doesn’t seem to increase the risk of stroke and heart disease in most people.
Caffeine seems to raise blood pressure when you consume it at high doses or prior to exercise as well as in the people who rarely consume it. But these effects may only be temporary so it’s best to monitor your response.
All studies show that it raises the blood pressure due to its stimulatory effect on the nervous system.
Elevated blood pressure is a risk factor for stroke and heart attack because caffeine may damage the arteries over time. Caffeine can restrict the flow of blood to your brain and the heart.
Well, the caffeine effect on blood pressure seems to be temporary in some people. But also seem to have the strongest impact on those people who aren’t used to consuming more caffeine.
High caffeine intake has also been shown to raise blood pressure during exercise in healthy people as well as those with mildly elevated blood pressure.
Therefore, paying attention to the dosage and timing of caffeine is important, especially if you already have high blood pressure.
Some researchers suggest that caffeine can reduce muscle activity in the fallopian tubes, which carry eggs from the ovaries to the womb.
This could mean that it can reduce a woman’s chances to become pregnant about 27 percent.
5. How Much Caffeine In A Cup Of Coffee Cause Fatigue
Tea, coffee, and other caffeinated beverages are well known to boost energy levels. It also causes the opposite effects on the body by leading to rebound fatigue after the caffeine leaves your system.
One review found that drinking caffeinated energy drinks can increase alertness and improve mood for several hours.
In this study participants often feel more tired than usual the following days.
If you continue to drink lots of caffeine throughout the day, it can avoid the rebound effects. It also may affect the ability to sleep.
The factors that affect how much caffeine in a cup of coffee include the brewing method, the number of coffee grounds, and the type of bean that a person uses.
Typically an 8-oz cup of coffee provides around 80-100 mg of caffeine, but some coffee drinks contain significantly more caffeine.
Some other sources that contain caffeine are energy drinks, some pain-relieving medications, chocolate, and soft drinks.
The side effects of consuming too much caffeine include jitteriness, sleeping difficulties, headaches, and gastrointestinal issues.