(Last Updated On: September 13, 2021)

Who doesn’t love a good cup of coffee in the morning? I know I certainly do! Having that extra energy boost helps me wake up and feel energized to face the day ahead. Since I am such a fan of coffee and I drink it every day, I decided to find out the positive and negative effects of coffee on the body. Is my daily cup of coffee doing more harm than good? Or is it better for me than I realize?

Finding out these answers is important to me, and that’s why I decided to share what I have found with you! So you too can decide for yourself if your cup of coffee is good or bad for you.

21 Positive and Negative Effects of Coffee that Will Freak You Out!

Positive Effects of Coffee

Let’s start off with the good stuff, and by good stuff, I mean the health benefits of coffee. Caffeine is one of the most consumed psychoactive chemical substances in the entire world. Is it the positive benefits of coffee that make this so? Or is it the different varieties and tastes? Whichever it is (personally I think it’s the benefits), with so many people indulging in their daily cup of coffee, or two, there has to be a reason behind it!

#1 Coffee will boost physical performance


One of the most popular reasons why people drink coffee is for the additional caffeine they will receive from just one small cup of hot or iced coffee. When you drink a cup of black coffee just an hour before you decide to work out or indulge in physical activity, you can actually increase your physical performance. Think: faster, harder, sweatier.

According to a published study with the US National Library of Medicine, you can actually increase your physical performance by at least 11-12 percent. The additional high levels of energy provided from the simple cup of coffee can allow you to workout longer and do more strenuous activity. That added boost of energy is what gets most people through their workout. I know it certainly helps me!

#2 Coffee can help you to shed those extra pounds

lose weight

Weight is an issue that many adults struggle with and luckily, coffee can help out. Coffee naturally contains high levels of potassium and magnesium, both of which help to fight off those sugary cravings. This is because these vital minerals will help your body to use insulin and regulate your blood sugar.

Not to mention, coffee will also help you to burn those unwanted fat cells since coffee will help to break them down and turn them into the fuel your body needs. Since the caffeine in coffee helps to kick start your metabolism, you will soon find, that with regular coffee drinking (2-4 cups of coffee per day) you will be shedding those unwanted pounds and achieving a healthier state of being.

#3 Coffee will hone your focus and keep you alert


Another popular reason why coffee is a drink of choice for most is because of fact it can help with your overall alertness and focus. When you drink coffee moderately, say 1-6 cups per day, the coffee will help you to improve your alertness and mental focus.

When you drink your coffee, the caffeine will enter your bloodstream and travel throughout your body. You may feel your heart rate quicken, yet your mind will stop wandering and you will be able to hone your focus while ever still increasing your alertness on the job in front of you. It’s no wonder why office workers love to have an afternoon coffee. They can get past their sleepiness, and power into the work ahead to finish out their day.

#4 Coffee can help you live longer

live longer

Everyone wants to have a long and healthy life, and coffee can be your secret weapon. Scientific studies have proved that coffee drinkers end up reducing their risk of premature death by at least 25% compared to those who do not drink it. The secret to longevity is as easy as indulging in one of the world’s most popular hot beverages.

#5 Coffee can significantly reduce the risk of cancers


Drinking up to four cups of coffee per day can help to significantly reduce your risk of prostate cancer if you are male, and endometrial cancer, if you are female. I’m talking by 20 to 25 percent, which can make a big difference!

Furthermore, drinking coffee can also help to reduce your risk of getting one of the most common strains of skin cancer. Since skin cancer can occur to nearly anyone of any age, reducing your own risk by sipping a latte or your iced coffee can seriously be a lifesaver. And if you’re a sun lover like me, this is important!

#6 Coffee can help reduce the risks of having a stroke

old people

As an avid coffee drinker, say at least two to four cups of coffee each day, you are helping your body to lower the risks associated with having a stroke later in life. This is due to the fact that the compounds in the coffee can produce healthy activity in the areas of the brain that are affected by stroke.

If you have a family history of stroke, consider drinking coffee regularly to help reduce your chances of having a stroke when you are older.

#7 Coffee provides antioxidants


Coffee contains many vitamins and minerals naturally, yet one amazing benefit to drinking coffee would be the fact that it is packed with antioxidants. Antioxidants help to heal your body’s cells and to remove any toxins present as well as fight against free radicals in your system.

In addition, antioxidants will give your body the immune boost it needs to help stay healthy and strong. The antioxidants will help rid your body of toxins and infection while still increasing your cell production. Plain and simple, our bodies crave antioxidants and if you can provide what your body needs with a simple cup of coffee each day, you should!

#8 Coffee can help to protect your brain


Drinking coffee will give you a major boost of caffeine. This caffeine soaring through your veins will help to significantly reduce your chances of developing cognitive conditions in your later years. Drinking at least one to two cups of coffee each day will lower your risks of dementia as well as Alzheimer’s disease. Keep your brain safe by drinking coffee, it’s that simple!

#9 Coffee can brighten your day

happy day

A nice cup of hot coffee in the morning will help to wake you up and get you ready for the day ahead of you. But did you know that your morning cup of jo’ will also help to brighten your mood?

The caffeine will stimulate your central nervous system and boost the production of your neurotransmitters. These neurotransmitters will send noradrenaline, dopamine, and serotonin through your body which will leave you feeling happier, lessen any depression you may have and even help to reduce the risk of suicide.

In fact, drinking coffee twice per day will prevent the risk of suicide by a whopping 50%. So next time you’re feeling blue, treat yourself to a hot cup of coffee.

#10 Coffee can reduce the risks of Parkinson’s Disease

Another cognitive condition that is common to develop in old age would be Parkinson’s disease. Reduce your risk by regularly drinking coffee. As a matter of fact, those who drink coffee regularly (at least 1-3 cups of coffee per day!) will decrease their risk of developing Parkinson’s disease by twenty-five percent. Studies have recently shown that the chemicals in coffee will produce activity in the areas of the brain that can be affected by this debilitating disease.

Negative Effects of Coffee

Ok, now that you are familiar with how great coffee can be by discovering the good effects of coffee, let’s discuss the not-so-great things about coffee. Because while there are a plethora of health benefits to drinking coffee regularly, there are also associated risks and disadvantages to drinking coffee that you need to be aware of. Some of these negative effects may be common knowledge, yet others might downright shock you! Read on to discover the negative effects of coffee and caffeine.

1. Bad coffee is toxic

When you get a bad cup of coffee, whether it is burnt or over-brewed, it might not taste the way you want it. And yes, many would think that this would qualify the coffee to be bad. In this instance, I’m talking about coffee that has beans that are full of impurities or even over-ripened.

When you drink a low-quality coffee, even with just a single bean that is overripe or filled with impurities, you place yourself at risk of developing headaches, feeling sick, or just overall feeling not so great.

These feelings can be avoided if you drink a high-quality, trusted brand of coffee.

2. Too much coffee can be lethal

Yes, while it might seem unbelievable, drinking too much coffee can actually be lethal. Within a short amount of time, if you drink twenty-three liters of coffee, you will end up overdosing on caffeine. The lethal dose is approximately 10-13 grams of caffeine in the system.

Although you will be vomiting by that point, because 23 liters of liquid is too much for the body to handle, the caffeine will still be ingested. While this can be a risk, 23 liters of liquid being drunk in a short amount of time, is actually very lethal, even if that liquid just so happens to be water.

3. Coffee can cause restless nights and sleeplessness

Due to the caffeine present in coffee, you can end up having feelings of restlessness or end up losing sleep. This just so happens to be one of the major negative effects of caffeine on many individuals, which is why some people choose to avoid coffee altogether.

It is recommended not to exceed the maximum dose of 400 mg of caffeine per day. If you are sensitive to caffeine, keep it light and make sure you do not drink coffee late in the day as it can affect your sleep. Since there are many different strengths and variations of coffee on the market, you are probably already aware of what types suit you and which ones do not. While one coffee might be perfect for you, it could wreak havoc on your friend. This is due to the fact that the amounts of caffeine that are safe for consumption are actually hard-coded into our DNA. Freaky right?

4. Coffee and babies don’t mix


Of course, you should never give babies a cup of coffee. That goes without saying. However, it is highly debatable whether or not pregnant women should drink coffee due to the caffeine that is present. There have been numerous studies on how coffee affects the fetus. One thing is for sure that fetuses in the womb are highly sensitive to caffeine and it can end up affecting their overall development in the womb.

If you are a heavy coffee drinker and you become pregnant, it is recommended to either cut your coffee consumption down to a maximum of one cup per day. Or you could switch to decaf.

5. Coffee can cause issues for those with high cholesterol

Those who are affected by high cholesterol should be wary as to what type of coffee they consume. Coffee beans will contain kahweol and cafestol. These two major ingredients in coffee beans will directly raise the LDL cholesterol levels in the body. Cafestol and kahweol will be found in Turkish coffee, espresso, French press, and Scandinavian cooked coffee. If you suffer from high levels of cholesterol, it is best to stick to filtered coffee to play it safe.

6. Drinking coffee on an empty stomach can wreck-havoc


Sometimes you roll out of bed and just need to have your cup of coffee before you can begin to think straight or begin to plan the day ahead. However, it is important to realize that drinking coffee on an empty stomach can actually cause more problems than you think.

Coffee can aggravate the stomach lining, especially if you have a sensitive stomach. In addition, if you are prone to IBS, Crohns disease, gastritis, or have an ulcer, the coffee will wreck-havoc upon your delicate digestive system. Your small intestine lining will also be at risk since the coffee will be the first thing to arrive in that part of the digestive system.

Drinking coffee on an empty stomach can cause you to have stomach cramps, abdominal pain, diarrhea, and/or even constipation. So make sure you get a light snack or have a meal before you indulge in your daily coffee.

7. Coffee can cause heartburn

As soon as you drink a cup of coffee, your lower esophageal sphincter will become relaxed. This can be a problem for those who have acid reflux disease and/or are prone to developing heartburn. This muscle, albeit small, should remain tightly closed so it can prevent the contents of the stomach from going where they should not be going.

Even if you end up drinking a cup of decaf, you can still be prone to having heartburn afterward. Many scientists believe that the acidic content or other compounds in the coffee cause these problems.

8. Coffee is a laxative

Ok, it is no secret that coffee is a natural laxative and many coffee drinkers choose to use coffee to, well, get the train out of the station so to speak.

Since coffee will stimulate the peristalsis, you know, giving you the urge to go to the toilet, it can end up disrupting the natural process of your body’s digestive system. When you stimulate the peristalsis you will end up promoting an increase in gastric emptying. This can happen too quickly and the contents of your stomach will move faster through the digestive system and will not be broken down properly.

When you have partially digested food in your system it will make it more difficult to pass through your body. You will also reduce the number of nutrients being absorbed into your body. To make things worse, you can irritate and even damage your gastrointestinal tract.

While this is definitely true of caffeinated coffee, the same can be said for decaf. So if you have a sensitive digestive system and/or gastrointestinal tract, be careful when drinking coffee.

9. Coffee affects your mineral absorption

Those who are heavy coffee drinkers may find it difficult to intake enough minerals into their system, even if they are adding supplements or vitamins to their daily diet. This is caused by the way that coffee affects your iron absorption within your stomach. It will also affect your kidney’s ability to absorb zinc, calcium, magnesium, and other vital minerals.

While all of the above minerals are important for your digestive and your overall health, it can be especially worrying when it comes to retaining magnesium. Many adults are already suffering from low levels of magnesium. Magnesium is vital for digestive support and maintaining bowel regularity.

10. Darker roasted coffee contains Acrlyamide

First things first, Acrlymide is a compound that is found in coffee that is a potential carcinogen. Carcinogens can cause cancer. Coffee that is roasted at very high temperatures will end up forming the dangerous acrylamide since the high temperatures will draw it out from the beans.

The darker roast the coffee has, the higher the temperature it was roasted at. These are the beans you will need to be wary of. Coffee is actually one of the main causes and sources of Acrylamide consumption.

11. Coffee can cause tension and stress you out

stress out

As I mentioned earlier, drinking coffee can release feel-good chemicals in your brain that will leave you feeling happier and brighter. Yet at the same time, coffee can also cause your brain to release other naturally occurring chemicals that can negatively affect you.

When you drink a lot of coffee, you will promote the release of what are known as stress hormones. The stress hormones that will be released include cortisol, norepinephrine, and epinephrine. These stress-related chemicals will cause a reaction in your brain and body known as the flight or fight reaction.

Many coffee drinkers will drink coffee for the added energy boost, but for some, it can leave them feeling aggravated and even jittery. Although a cup of coffee can help you get through a mountain of paperwork or the daily grind when it leaves you feeling not so great shortly after consumption, you may feel the negative outcomes outweigh the benefits.

Furthermore, the stress hormones will cause the digestive system to be interrupted. Once you have entered the flight or fight mode, your body will react in a way to preserve any resources it has. This means any fat cells will not be burned away and your metabolism will slow right down.


While many heavy coffee drinkers will praise the benefits of their caffeine addiction, there are some precautions you will need to keep in mind before you pick up your next cup of coffee. If you are highly sensitive to caffeine, pregnant, have digestive issues or problems, or you are feeling bad after a cup of really strong coffee, maybe it’s best to avoid it for a while or at least reduce your intake. Or at the very least you can switch to decaf or find another type of coffee to drink and enjoy.

That being said, I truly believe that the positive benefits you can receive from drinking coffee heavily outweigh the negative ones. Because honestly, I don’t think I could live without my daily cup of coffee!

Did you find any of these positive and negative effects of coffee to be interesting, helpful, or downright strange? Will you have a second thought before your next cup of coffee? Are you going to leave your grinder alone from here on? Let me know!


Annalise O'Conner is a Registered Dietitian and Personalized Nutritionist. She is a lecturer at the University of California, Berkeley, teaching nutrition in the School of Public Health and APAN (Asian Pacific Islander American Network) Email: [email protected]

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