Coffee, A True Wonder Drug?

Imagine a world without coffee

Guess what would be the average productivity in our countries if people had to start the day without having their cup of coffee first: it would probably look like a remake of Zombieland in most companies and organizations. Some people need that first java cup before they are able to say a single word. Some others are less addicted to coffee but it is still part of their morning routine and they probably underestimate the effects that a cup of Joe has for their body and mind. And we don’t even mention the java cup or two which fortunately prevent most offices to look like dormitories in the afternoon.

This sort of nightmare scenario refers of course to the physiological effects of coffee which are well-known, coffee being one of the most consumed beverages around the world and studied since years in thousands of medical studies, analyzing the risks and benefits for adults and even children. Then, why this buzz around coffee these last weeks? Simply because a recent study, published in May 2012 by the New England Journal of Medicine, concluded after 13 years of follow-up of almost 230,000 men and 175,000 women that coffee consumption decreased all-cause mortality by more than 10%.

We have a special interest in this topic for several reasons:

  • Caffeine is an alkaloid, this fascinating family that we have described through the example of ephedrine.
  • From a scientific point of view, it is interesting to see how coffee has been perceived in terms of risks and benefits for health: doctors used to tell us that coffee was bad us and now they say it’s good, what should we believe?

We will go through these risks and benefits based on the latest studies, reflecting the current point of view of the medical community. Then we will detail what belongs to caffeine, based on studies which compared the effects of coffee and caffeinated coffee.

Benefits of your daily java cups

Based on a serious body of research, there is today a strong evidence that coffee consumption plays a positive role in the following conditions:

Coffee can lower the risks of Type 2 diabetesType 2 diabetes
Due to its strong antioxidant capacity and improved glucose metabolism, coffee can reduce the risk of type 2 diabetes up to 35% [1] [2] [3] [4]



Coffee can prevent neurodegeneration (Parkinson, Alzheimer)Neurodegeneration
Lower risk of Parkinson’s disease [5] [6] and dementia such as Alzheimer’s disease [7] [8] [9], up to 60% and even 80% depending on studies.



Coffee reduces the risk of cardiovascular diseasesCardiovascular and cerebrovascular diseases
The counter-intuitive result of studies shows that coffee can reduce heart rhythm problems and lower the risk of stroke up to 20% [10] [11] [12] [13] [14] [15]



Coffee prevents several cancersCancer
Coffee drinkers have fewer cases of cancers such as head and neck [16] [17], basal cell carcinoma [18], breast cancer [19], endometrial cancer [20], oral, esophageal and pharyngeal cancer [21], aggressive men’s prostate cancer [22] and colorectal cancer [23]. This is most probably due to the antioxidant and antimutagenic properties of coffee. [24]



Coffee lowers the risk of depressionDepression
A Harvard study found that women who drink four or more cups of coffee daily have a 20% lower risk of depression. [25]




Coffee helps your liverLiver Disease
Probably due to its strong anti-fibrotic properties, coffee acts as a protection for the liver against cirrhosis [26] and hepatocellular carcinoma. [27]




Coffee increases the effects of pain killers for headachesOther conditions
Coffee consumption appears to lower also the risk of gallstones and gallbladder disease [28] [29], gout [30], headache [31], dry-eye syndrome [32] and even dental caries [33].

Negative effects of coffee

While recent studies add to the list of benefits associated to a reasonable coffee consumption, many health professionals keep drawing attention on the risks linked to an excessive number of coffee cups per day. Some of the following conditions are still a matter of debate between medical experts, due to contradictory results of the concerned studies. In that case, further research is needed but meanwhile it is safe to consider that people who drink too much coffee may be exposed to these risks:

Coffee does not harm your heartHeart rhythm problems (cardiac arrhythmias due to vasoconstriction) may occur in case of heavy coffee drinking habits. [34]




Coffee will not cause hypertensionBlood pressure and risk of hypertension: this point is unclear, as different studies presented contradictory results, the latest ones show no relation between coffee drinking and clinical hypertension. [35]




Coffee may increase cholesterolCholesterol levels may go up in case of excessive consumption of unfiltered coffee. [36]




Coffee may be linked with osteoporosisOsteoporosis is due to the loss of calcium and magnesium in urine at high levels of caffeine per day (more than 600 ml) and can affect older people.




Coffee may increase the risk of rheumatoid arthritisChemical solvents used to produce decaffeinated coffee, such as methylene chloride, trichloroethylene or ethyl acetate, might explain a higher risk of rheumatoid arthritis.




Pregnant women should not drink too much coffeePregnancy: the excess of coffee (more than 7 cups) is suspected to raise the risk of low birth rate, miscarriage, premature birth and stillbirth [37]. It is recommended to pregnant women to have a moderate coffee consumption.




Heartburn is frequently associated with coffeeHeartburn results from the acidic nature of coffee, but it has been found that espresso and dark-roasted coffee may contain a substance that limits the production of acid by the stomach. [38]




Coffee may cause sleep disorders (insomnia)Sleep disorders (insomnia, nervousness, anxiety) [39]: depending on individual sensitivity, these side effects can occur until caffeine is totally processed by the liver (half live of 5 to 7 hours).




Being diuretic, coffee may cause dehydrationDehydration: coffee acts as mild diuretic.




Coffee may develop addiction and withdrawal syndromesAddiction: considered as low by most experts, due to the quick development of a tolerance to caffeine. The main symptoms of withdrawal include headache, irritability and fatigue. [40]

Coffee or caffeine?

Some might be surprised by this question but it makes sense: caffeine is naturally the important ingredient in coffee but other compounds such as antioxidants play also an important  role in the above mentioned health benefits. This is why several studies found the same effects for coffee and decaffeinated coffee. In fact, you can have coffee without caffeine, but also you might take caffeine without coffee: during the decaffeination process, may it be through water extraction or by chemical solvents, caffeine is recovered by manufacturers and sold alone as tablets. Thus three intake possibilities exist: coffee, decaffeinated coffee or caffeine alone. We will detail in our next article the effects of caffeine combined to ephedrine in EC stacks for weight loss purpose, in this section we would like to review the main differences found by medical studies between the consumption of coffee and decaffeinated coffee.

  • Caffeine has been identified as the probable key factor for the risk reduction in several conditions, thereof breast cancer, skin cancer, gallstones and gallbladder disease, mental sharpness especially by older people, because people who drank decaffeinated coffee did not experience the same benefits.
  • On the other hand, one study found that people who had 2 cups of decaf coffee per day had half the risk of rectal cancer, compared with people drinking normal coffee.
  • All other benefits mentioned in the previous section appear for both coffee and decaffeinated coffee: prevention of diabetes and strokes, reduction in endometrial or prostate cancer among others.

The researchers explain it by the fact that both coffee and decaffeinated coffee share protective components such as minerals and antioxidants, methylpyridinium for instance, which lower inflammation and protect cells from oxygen-free radicals.


Is coffee good or bad for us? Based on their current knowledge, today medical experts say that they have few proven benefits but a growing list of potential benefits, especially in case of a moderate coffee consumption.
Regarding decaffeinated coffee, it appears that coffee with caffeine has more health benefits, as it brings the full range of effects and not only those associated with antioxidants properties.
Why is decaffeinated coffee so popular then, or in other words, why are so many people deliberately avoiding caffeine? We will give our own answers in the next article.

Recommended posts about observational studies: here the Cross-Sectional StudyWhy Do People Drink Decaffeinated Coffee?
Knowing the benefits of a moderate coffee consumption, we can legitimately raise the question. In this post we analyze medical studies’ methodology (observational versus interventional studies) explaining why doctors were lacking scientific evidence of health benefits of coffee and caffeine.



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By Mike Budd.