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Coffee & Health

How Much Coffee Is Too Much?

There’re several bioactive compounds found in coffee. Coffee is the biggest source of dietary antioxidants for most people. Also, research findings indicate that people who drink coffee regularly have a reduced risk of developing conditions such as neurological disorders, liver diseases, and type 2 diabetes.

However, many people wonder whether consuming excess coffee has any health risks. Thus, you may want to know the safest amount of coffee to drink. In this article, you’ll know the amount of coffee that’s safe to drink without any health risks.

man drinking a lot of coffee while at work

Caffeine Content in Coffee

Caffeine is the most active compound in coffee. In fact, it’s the most consumed psychoactive compound across the world.

The caffeine content in coffee varies significantly depending on the type of coffee. Generally, the caffeine content in coffee ranges between 50 to more than 400 milligrams per cup. For instance, a small serving of home-brewed coffee can contain about 50 milligrams of caffeine while a 475 ml (16-ounce) Starbucks grande serving can contain at least 300 milligrams of caffeine. Generally, an average 240 ml (8-ounce) cup of regular coffee contains about 100 milligrams of caffeine.

Many studies suggest that consuming up to 400 milligrams of caffeine daily (about 945 ml or four cups of regular coffee) is generally safe for the majority of healthy adults. Some individuals consume a higher amount of caffeine than the recommended amount without any health issues.

It’s also worth noting that caffeine is also available from other sources such as tea, energy drinks, soft drinks, certain medications, and chocolate.


Short-Term Signs of Excessive Caffeine Intake

In case you consume excessive coffee within a short time, you might experience physical and mental symptoms such as:

  • Anxiety
  • Restlessness
  • Upset stomach
  • Dizziness
  • Tremors
  • Fast heartbeat
  • Insomnia
  • Irritability

If you happen to experience these symptoms after consuming coffee, then you’re likely sensitive to caffeine. In this case, consider reducing your coffee consumption or avoid it altogether. Although it’s likely to die as a result of caffeine overdose, it’s very unlikely for this occurrence to result from drinking coffee alone. For this to happen, you’ll need to drink at least 100 cups of coffee within a day.

However, there’re a few but rare instances of people succumbing as a result of consuming caffeine supplements.


People Tolerate Different Amounts of Caffeine

Generally, caffeine tends to affect people differently. There’re various genes that affect an individual’s sensitivity to caffeine. These genes have an effect on how caffeine is broken down in the liver by enzymes. Receptors in the brain are also affected by consuming caffeine.

Also, the effects that caffeine has on an individual’s sleep are genetically determined. Thus, some individuals may consume coffee and sleep immediately whereas others stay awake overnight after consuming coffee.

An individual’s genetic makeup determines the amount of caffeine they can tolerate. Some individuals tolerate high amounts of caffeine while others can only tolerate a little amount of it. Most people tolerate a moderate amount of caffeine.

You can also acquire caffeine tolerance. Individuals who consume coffee regularly tolerate more caffeine than individuals who consume it infrequently.

It’s worth noting that certain medical conditions may affect caffeine sensitivity. If you’re suffering from health conditions such as diabetes, hypertension, panic disorder, anxiety, and heart arrhythmia among others, you may only tolerate a little amount of caffeine. It’ll help to consult your doctor to know whether you can tolerate caffeine depending on your health situation.


Coffee and Increased Longevity

Although excessive caffeine intake may have serious side effects, taking coffee moderately is linked to numerous health benefits. In fact, research shows that coffee intake increases longevity. For instance, in a study done on several people aged 50 to 71, the participants who took four to five cups of coffee daily had a lower risk of dying over the period of the study, which was 12 to 13 years. These results are backed by other reviews.

However, there’re mixed results in the research. For instance, recent research found that consuming at least four cups of coffee daily was associated with a higher risk of dying among individuals below 55 years old.

It’s worth noting that most of these studies didn’t specify whether a cup of coffee was a standard 240 ml (8-ounce) cup or generic vessels of different volumes that many individuals often use to take coffee. However, variations in cup sizes aren’t very significant.


Coffee and Reduced Health Risks

Coffee is linked to reduced health risks for several illnesses including:

  • Depression– Research shows that consuming at least four cups of coffee daily is associated with a reduced risk of developing depression by 20 percent and a reduced risk of committing suicide by 53 percent.
  • Diabetes– Drinking more coffee regularly is shown to reduce the risk of developing diabetes. Research shows that each cup of coffee per day reduces the risk of developing diabetes by 7 percent.
  • Liver cancer- Every two cups of coffee per day reduces the risk of developing liver cancer by 44 percent.
  • Liver cirrhosis– Taking at least four cups of coffee per day reduces the risk of developing liver cirrhosis by as much as 84 percent. Liver cirrhosis is a severe result of certain liver diseases.
  • Parkinson’s disease– Drinking coffee is linked to a lower risk of developing Parkinson’s disease. Those who drink at least five cups of coffee per day experienced the hugest reduction.
  • Alzheimer’s disease– Research shows that taking three to five cups of coffee daily is associated with a 65 percent reduced risk of developing Alzheimer’s disease.

Considering the above health benefits, it’s healthy to drink coffee daily (preferably four to five cups). However, the above results are from observational studies. Thus, they don’t prove that the reduced risk of developing the diseases was caused by coffee. They only show that individuals who drink coffee stand lower chances of getting these diseases. Regardless, it’s worth taking note of these results.

Decaf coffee may also have similar beneficial effects. However, Parkinson’s disease would be an exception as it’s mainly affected by caffeine, which is minimal in decaf coffee.


Caffeine and Pregnancy

Studies show that caffeine can get through the placenta, thereby reaching the fetus. The fetus appears to have problems with metabolizing caffeine.

Research shows that high caffeine consumption during pregnancy may increase the risk of premature delivery, miscarriage, low birth weight, and stillbirth.

Pregnant women are advised to limit caffeine intake to between 100 to 200 milligrams per day, which is about 240 to 475 ml or one to two cups of coffee. Regardless, many experts advise pregnant women to avoid taking coffee to be on the safer side.


Recommended Intake

Research shows that the best amount of coffee to take per day is about four to five cups. Drinking this amount of coffee is associated with a reduced risk of dying prematurely and a reduced risk of developing numerous health conditions that affect millions of individuals across the globe. However, this doesn’t necessarily mean that it’s a must to take coffee.

If you have certain health conditions, sensitive to caffeine, or you just dislike coffee, then avoid it. Also, if you love taking coffee but it gives you sleep problems or anxiety, then reduce your intake or eliminate it from your diet altogether.

It’s also worth noting that adding high-calorie and unhealthy ingredients or sugar to coffee can invalidate its benefits. Regardless, you can optimize your coffee intake to enjoy maximum benefits.



Research has proven that coffee offers numerous benefits. There’s little evidence that links coffee to any significant harm. While the optimal amount of coffee to drink per day is four to five cups, several people tolerate more amounts of coffee without any health problems. In case you like taking coffee without any side effects, then you shouldn’t stop consuming it.


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