20 Caffeine Side Effects For Health (No.1 & 2 Uncompromising)

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The word “caffeine” is originated from German word “kaffee” and  French word “café”, which means “coffee”. Caffeine has chemical name that is is 1,3,7-trimethylxanthine, based on its formula, C8H10N4O2. Caffein is one kind of Alkaloid in exact form of methylxanthines alkaloid  or a chemical compound as produced by plant from metabolism of nitrogen. In the pure form it is white crystalline purine with bitter taste. Caffeine is found in more than 60 plant species worldwide. Coffee bean is the most well known source of caffeine else the cocoa, tea, berries of guarana plant also contain caffeine. We also know that caffeine also one of ingredients that we found in beverages such as energy drink. Caffeine is belong to psychoactive drug or psychotropic which is a chemical compound that can changes brain function and results in changes of mood, perception, or consciousness. Unlike other psychoactive drug which is illegal, the usage of caffeine is legal.

History Of caffeine

Caffeine has a long history worldwide for thousands years and every country has its own story. There is a folk story that grew among generations in Ethiopia which mentioned a farmer who had goats in his era found that his goats were restless and “dancing”.  On the next day, farmer found that his goats consumed small red berries from a plant. Later these berries become famous today as dried coffee beans. Other story of cocoa and tea were found in some countries which both also contain caffeine and contribute the caffeine history. On 2737 B.C a story Chinese Emperor Shen Nung started to sipped hot brewed tea which he found tea leaf on his cup mistakenly and later chinese start to consumed tea leaves as healthy beverages.

On 1519 when Colombus arrived on America, Aztecs introduced cocoa or chocolate to those spanish explorer then later cocoa also made its way to Europe. On 1820, a German Scientist named Friedrich Ferdinand Runge was the first man who extracted caffein from cocoa bean into the purest form, a white powder caffein and then the extraction of caffeine lead a way to created the first caffeinated soft drink in 1880s. Today, we can almost found any beverages in store which contain caffein and people start to consumed on daily basis.

How Much Caffeine Contained in some Foods And Beverages?

Some foods that are largely sold today contain some amount of caffeine. Here you can see some foods item and how much caffein contained in those items.

Popular Foods                                                   Serving                            Caffeine Quantity (mg)

Beverages                                                       oz           ml  or g


Espresso (single)                                                1                  30 ml                                          56-75

Espresso (double)                                              2                 60 ml                                            150

Cappuccino                                                         8              237 ml (1 cup)                                150

Brewed                                                                 8              237 ml                                              135

Roast and ground, percolator                         8              237 ml                                              118

Roast and ground, filter                                   8              237 ml                                              179

Roast and ground, decaffeinated                   8              237 ml                                                3

Instant                                                                 8              237 ml                                            76–106

Instant decaffeinated                                       8             237 ml                                                 5



Regular blend                                                    8               237 ml                                           43

Green                                                                  8               237 ml                                            30

Instant                                                                8               237 ml                                           15

Loose tea or tea bags                                       8               237 ml                                           50

Decaffeinated 8 237 ml 0


Cola type soft drinks

Regular cola                                                    12            355 ml (1 can)                              36 – 46

Diet cola                                                          12            355 ml                                            39 – 50


Energy Drinks (ex. Red Bull)              8             250 ml                                               80


Cocoa based products

Chocolate milk                                                8            237 ml                                                 8

1 envelope hot cocoa mix                              8            237 ml                                                 5

Candy, milk chocolate                                    1              28 g                                                    7

Candy, sweet chocolate                                  1              28 g                                                  19

Baking chocolate, unsweetened                     1             28 g                                            25 – 58

Chocolate cake                                              2.8             80 g                                                 36

Chocolate squares (brownies)                       1.5           42 g                                                10

Chocolate mousse                                          3.2             90 g                                                15

Chocolate pudding                                         5.1           145 g                                                 9


(Table adapted from de Caffeine and Food. Health Canada, accessed on 15 March 2016

Based on table we can measure our daily caffeine consumption. If a cup of coffee (8 oz) contain 85mg caffeine, it means based on Recomended Daily Allowance of caffeine, 300mg a day we can consume 3 cups of coffee savely.

Caffeine Effect and Metabolism

After consuming caffeine, the body will not accumulate the caffeine over time and it is usually excreted within several hours after consumption. This is why people found the smell of coffee in urine after some hours drinking coffee. The time of excretion of coffee varies among individuals, but normally a healthy adults will metabolize and excrete caffeine quickly.

Caffeine is known as brain stimulator which can produce consciousness and people who feel sleepy tend to drink or consume caffeine to get rid sleepiness. The effect of caffeine may vary to every person. Some people who consume coffee during evening and it does not effect to their ability to sleep, but others found that only small amount of caffeine can keep them awake . This condition happen when every individual tend to have their own daily  acceptable level of caffeine consumption based on their experience with caffeine.

Caffeine sensitivity which can rise the chance health problems depend on many factors including amount of intake, body rate metabolism, weight, and physical health. Based on Food and Drug Administration, caffeine is categorized as “generally recognized as safe” (GRAS). Caffeine can be toxic substance if it consumed more than 10grams per day. A cup of coffee can contains 80-175mg of caffeine depending on what kind of been is used to make the coffee and also the process during preparing. So consume 50-100 cups a coffee can be lethal, but no one drink that amount of coffee in a day right? Even so, if you consume pure form of caffeine as supplement, just a tablespoon size of caffeine can cause death or lethal.

Is caffeine addictive? 

We used to think that consuming caffeine can cause addiction. According to the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV, 1994) and paraphrased by Drewnowski and Bellisle (2007), Addiction can be describe as a situation which involves compulsive and repeated use of a substance that poses a threat to physical, social and economic health.  Substance dependence is built around persistence in procuring the substance of choice, in the face of obstacles, and despite psychological, social and economic costs.”

Based on the definition of previous phrase so caffeine does not fit to the criteria of addictive one. Caffeine can acts as mild central nervous system stimulator depend on the amount of caffeine consumption. Some individuals may think they got addictive to caffein since they experienced mild temporary symptoms of discomfort such as headache, drowsiness or fatigue. Those effevts can absolutely be removed by reducing or avoid caffeine intake over several days.

Side Effects of Caffeine

Even caffeine has proved to give some benefits for human such as calming and stimulates the nervous sytem also can get rid sleepiness during daytime, caffeine also has bunch side effects that you should know.

1. Caffeine May Cause Insomnia

Caffeine which acts as stimulator of central nervous system can also increases mental alertness and help someone to stay awake for longer time. Some research has shown that consuming caffeine provokes secondary effects to people who have certain sensitivity such as headache, irritability, nervousness and insomnia. Caffeine also inhibits deep sleep and make someone face difficulity to fall asleep and lowers the ability to wake easily. In other words caffeine can higher the risk of insomnia

2. Increase the risk of Heart Disorder and Hypertension

According to American Heart Association, many studies shown that there is a direct link between caffeine and coronary heart disease. Beside its role on stimulating central nervous system, caffeine also acts as cardiovascular system stimulant which can increase heart rate and resulting heart palpitations. From just consumption of 250mg caffeine the heart can increase the blood pressure of 6 to 8 mm Hg. So people who are suffering from heart problems especially those with cardiac arrythmia should avoid consuming caffeine so does the people who suffering hypertension. Some Individuals with genetically predisposed to metabolized caffeine slower than general people may have a higher health problem consuming caffeine if they have heart problems.

3. Higher Blood Sugar Level in Diabetes People

Caffeine can increase level of blood sugar on diabetic people when they consume 250mg or more amount of caffeine after meal especially those with diabetes type 2. In the study of Duke University researcher James D. Lane PhD and colleagues, people which consumed 250mg of caffeine increase their blood level to 8% than normally and it makes people with diabetes are harder to control their blood level.

4. Bigger Chance of Fractures

Based on US National Library of Medicine National Institutes of Health Journal, caffeine increases urinary calcium output and has been implicated as a factor in developing osteoporosis. Study also showed that high caffeine usage can increase the risk of fracture indirectly. Other study also show that caffeine can effect the intestine and decreasing the ability of intestines to absorb calcium.

 5. Promoting Stomach Ulcers.

Caffeine stimulates the hypersecretion of gastic acids and its knowly as highly acidic. Even decaffeineated coffee has more powerful stimulant of acid secretion and gastrin releasing. Caffeine also speed up the process of gastric emptying which can lead to highly acidic stomach pass to small intestine faster than normally. This condition may lead to stomach ulcer and intestinal tissue injuries.

6. Caffeine can cause Diarhoea and Fecal Incontinence

Caffeine can stimulate sensitive bowel and has laxatife effect to the body. This condition makes up the cause of diarhoea and caffeine also play as big contributor in Irritable Bowel Syndrom or IBS. Drinking coffee which contain caffeine in the morning can trigger the production of Bile which has function of fat metabolism. Some people are sensitive to bile so when the bile moves to intestine, it can cause irritation and body will be forced to wash the bile away from intestine with absorb more liquid and this condition may lead to diarhoea and fecal incontinence.

 7. Promoting Dehydration

Consuming more than 225 mg of caffeine a day (equivalent to one or two cups of coffee or five cups of tea) can increase urine production. As explained before that caffeine will be excreated soon from the body after consumption. And increase urine production so this may lead to dehydration. For those who are suffering from urinary incontinence and prostate problem, this effect can be harmful for them.

8. Inhibit Iron Absorption and Causing Anemia

Caffeine which work together with tanins in coffee or tea can inhibit the absorption of iron mineral which are needed in red blood productions. People with Anemia history should avoid to drinking caffeinated beverages together with meal.

 9. Elevates the Stress Hormones Level

Caffeine can elevates the level of stress hormones cortisol, adrenaline and norephineprine which can cause in rapid heart beat and anxiety.

10. Suppresses Immune System Function

The increasing level of stress hormones does not only effect to anxiety. It also can promotes Immune system suppression. This situation which induced by caffeine allow Helicobacter pylory ( Bacteria which Implicates Ulcer) can thrive in to the stomach and causing more health problems

11. Increase the risk of Spontaneous abortion (miscariage) in Pregnant Woman and Effect Infant During Breastfeeding

Woman who are pregnant is suggested to not consuming caffeine more than 300 mg per day. Pregnancy can also make the woman more sensitive to caffeine which has negative effects to the body. Furthermore, mother who consuming caffeine while breastfeeding can affect the baby sleeping patterns because caffeine also can be detected in breast milk one to three hours after consumption.

12. Effecting Heart and Breath While Medication

Consuming caffeine while taking any medications can cause negative effects by the increasing of heart beat and breath disturbance. Caffeine is ingredients which usually found as painkiller medicine combined with aspirin or parachetamol.  So when you have taken some medicine its better to not consuming any coffee or other beverages with caffeine.

13. Caffeine in Coffee Contributes to Caries in the teeth.

Caffein which contained in coffee can affect the teeth and harmful for health. Beverage that contain caffeine leave stains behind the teeth. Based on study of Donna J Phinney and Judy H halstead, authors of “Delmar’s Dental Assiting”  reported that consuming caffeine in high quantities can cause the teeth turn into yellow or brown and lead the degradation of teeth enamel which play role in keeping teeth strong and healthy.

14. Increase intraocular pressure in persons with glaucoma

Researcher has found that caffeine can increase the intraocular pressure in people who suffer from intraocular hypertension and even some people linked it to blindness.

15. Coffee may interfere with proper levels of cholesterol by inhibiting vitamins folate, B12 or B6.

A study by Klag and his Collegues from John Hopkins University School of Medicine of Baltimore in 2001 showed that there is relationship between coffee consumption and cholesterol level. Drinking caffeine from unfiltered coffee or which prepared by the process of perculator on an average of 6 cups coffee can increase the total level of cholesterol and LDL which also factor that causing heart disease.

16. Increase Incidence of Heartburn and GRED

GRED or gastroesophagus reflux disease is a digestive disorder which affected the lower esophageal sphinchter (LES) which has causing heartburn, or the sensation of pain behind the breastbone. Heartburn happen when there is reflux of syomach acid from the stomach into esophagus. It is known that 5-7% of the global population suffering from GRED. Further, GRED which untreaten can cause severe damage to esophagus including pain, dysphagia (difficulty swallowing), bleeding and choking. Caffeine can be dangerous for people with GRED because as mentioned before, caffeine cause reflux acid in stomach.

17. Promoting Muscle Twitches and spasm

Consuming caffeine from energy beverage which are over the dose of caffeine RDA may lead to muscular problem and spasm.

18. Causing Confusion and stuttering

Well known of the function of stimulating brain, the further usage of caffeine can decrease brain function and creating confusion, shattering even halutination.

19. Diuresis and Kidney Disorder

Body will excrete caffeine soon after it being consumed. This condition lead the blood to flow faster and pump it to kidney. High dose or long term usage of caffein will force the kidney to work more so it can be harmful and cause more urination even further kidney disorder may happen.

20. Caffeine intoxication, Coma and Overdose Death

Some data which are gain by Australian Researcher shown that many cases of caffeine intoxicated that causing coma and death found in people which were intoxicated by  high dose caffeine from energy drink.

Some Healthy Tips To Consume Caffeine

  • Instead of consume instant coffee we can use organic coffee to avoid more chemical addition in it.
  • Consume lower caffeine coffees such as Arabica beans rather than robusta beans  will be better for our body
  • Dont forget to drink plenty of water to avoid dehydration after consuming beverage which contain caffeine. This will help kidney to work easier because water reduce the blood thickness.
  • Take some food supplement like vitamin/mineral to replace lost minerals, and vitamins electrolyt which cause by caffeine diuretic effects.

Some people which are supposed to avoid consuming caffeine are :

  • Pregnant women and whom which breastfeed the baby
  • People with high blood pressure, high cholesterol, gall stone or heart disease
  • People with caffeine allergy or sensitivity to drug and people with mental illness, insomnia or anxiety.
  • Avoid to drink coffee before sleep if you need to wake up early in the morning and later force you to take more cups during the day
  • People with diabetes should not coffee after meals because it can increase blood sugar level

Those are the side effects of caffeine which has been proved by some research. So if you are coffee lovers or someone who love to drink caffeinated drink, its better to start reduce the caffeine intake and start more healthy life.