Side Effects of Too Much Caffeine

coffee beans

Coffee and tea are extremely healthy drinks. Most types contain caffeine, a compound that might improve your state of mind, metabolism and mental and physical efficiency.

Research studies have actually also revealed that it’s safe for the majority of people when consumed in low-to-moderate amounts.

Nevertheless, high doses of caffeine may have unpleasant and even unsafe negative effects.

Research has shown that your genes have a major influence on your tolerance to it. Some can take in a lot more caffeine than others without experiencing unfavorable effects.

What’s more, individuals who aren’t used to caffeine might experience symptoms after consuming what is usually thought about a moderate dosage.

Here are 9 adverse effects of too much caffeine.

Stress and Anxiety

Caffeine is understood to increase awareness.

It works by obstructing the impacts of adenosine, a brain chemical that makes you feel tired. At the exact same time, it sets off the release of adrenaline, the “fight-or-flight” hormonal agent related to increased energy.

However, at higher dosages, these results may become more pronounced, resulting in stress and anxiety and nervousness.

In fact, caffeine-induced anxiety disorder is among 4 caffeine-related syndromes noted in the Diagnostic and Statistical Manual of Mental Disorders (DSM), which is published by the American Psychiatric Association.

Exceptionally high day-to-day consumption of 1,000 mg or more per day have been reported to trigger anxiety, jitteriness and comparable symptoms in the majority of people, whereas even a moderate consumption may cause comparable impacts in caffeine-sensitive people.

Furthermore, modest dosages have actually been revealed to trigger fast breathing and boost tension levels when consumed in one sitting.

One research study in 25 healthy males discovered that those who ingested approximately 300 mg of caffeine experienced more than double the stress of those who took a placebo.

Remarkably, stress levels were comparable in between regular and less regular caffeine consumers, recommending the compound may have the exact same result on tension levels no matter whether you drink it repeatedly.

However, these results are initial.

Coffee’s caffeine content is extremely variable. For reference, a large (“grande”) coffee at Starbucks includes about 330 mg of caffeine.

If you see that you often feel worried or tense, it may be a good idea to take a look at your caffeine consumption and suffice back.


Caffeine’s capability to assist individuals remain awake is one of its most prized qualities.

On the other hand, excessive caffeine can make it difficult to get enough restorative sleep.

Studies have found that greater caffeine intake appears to increase the amount of time it takes to drop off to sleep. It might also reduce overall sleeping time, particularly in the elderly.

By contrast, low or moderate quantities of caffeine don’t seem to affect sleep extremely much in people considered “excellent sleepers,” and even those with self-reported sleeping disorders.

You might not recognize that too much caffeine is hindering your sleep if you undervalue the amount of caffeine you’re taking in.

Although coffee and tea are the most focused sources of caffeine, it is also discovered in soda, cocoa, energy beverages and numerous kinds of medication.

For example, an energy shot might include up to 350 mg of caffeine, while some energy beverages provide as much as a massive 500 mg per can.

Notably, the quantity of caffeine you can consume without impacting your sleep will depend on your genes and other elements.

In addition, caffeine taken in later on in the day might hinder sleep because its results can take several hours to disappear.

Research study has shown that while caffeine remains in your system for approximately five hours, the time period might vary from one and a half hours to 9 hours, depending upon the person.

One research study investigated how the timing of caffeine consumption impacts sleep. Scientists provided 12 healthy grownups 400 mg of caffeine either 6 hours prior to bedtime, 3 hours before bedtime or instantly prior to bedtime.

Both the time it took all 3 groups to drop off to sleep and the time they spent awake in the evening increased significantly.

These results suggest that it’s important to take note of both the quantity and timing of caffeine to enhance your sleep.

Digestive Issues

Many individuals find that an early morning cup of coffee assists get their bowels moving.

Coffee’s laxative result has been credited to the release of gastrin, a hormone the stomach produces that accelerate activity in the colon. What’s more, decaffeinated coffee has actually been shown to produce a comparable reaction.

However, caffeine itself also seems to promote bowel motions by increasing peristalsis, the contractions that move food through your digestion system.

Offered this result, it’s not surprising that big dosages of caffeine may result in loose stools or perhaps diarrhea in some individuals.

Although for several years coffee was believed to cause stomach ulcers, a big research study of more than 8,000 individuals didn’t discover any link between the 2.

On the other hand, some research studies recommend that caffeinated beverages might get worse gastroesophageal reflux illness (GERD) in some people. This seems to be particularly real of coffee.

In a little study, when 5 healthy grownups drank caffeinated water, they experienced a relaxation of the muscle that keeps stomach contents from going up into the throat– the hallmark of GERD.

Since coffee can have major impacts on digestion function, you may want to cut down on the amount you consume or switch to tea if you experience any concerns.

Muscle Breakdown

Rhabdomyolysis is an extremely serious condition in which broken muscle fibers go into the blood stream, leading to kidney failure and other issues.

Typical reasons for rhabdomyolysis consist of injury, infection, substance abuse, muscle stress and bites from toxic snakes or bugs.

In addition, there have actually been a number of reports of rhabdomyolysis related to excessive caffeine intake, although this is relatively uncommon.

In one case, a woman developed queasiness, throwing up and dark urine after consuming 32 ounces (1 liter) of coffee including roughly 565 mg of caffeine. Thankfully, she recuperated after being treated with medication and fluids.

Notably, this is a large dosage of caffeine to consume within a short duration of time, particularly for someone who isn’t utilized to it or is extremely conscious its effects.

In order to reduce the danger of rhabdomyolysis, it’s finest to limit your intake to about 250 mg of caffeine each day, unless you’re utilized to taking in more.


Despite all of caffeine’s health benefits, there’s no rejecting that it might end up being habit-forming.

A comprehensive review suggests that although caffeine activates certain brain chemicals likewise to the way cocaine and amphetamines do, it does not trigger classic dependency the method these drugs do.

Nevertheless, it might result in mental or physical dependency, particularly at high does.

In one research study, 16 individuals who generally taken in high, moderate or no caffeine took part in a word test after going without caffeine over night. Just high caffeine users revealed a bias for caffeine-related words and had strong caffeine yearnings.

In addition, the frequency of caffeine intake seems to play a role in dependence.

In another research study, 213 caffeine users finished questionnaires after going 16 hours without consuming it. Daily users had higher increases in headaches, fatigue and other withdrawal symptoms than non-daily users.

Despite the fact that the compound does not seem to cause real addiction, if you frequently consume a lot of coffee or other caffeinated beverages, there’s a great possibility you might become depending on its effects.


Overall, caffeine does not seem to increase the risk of heart illness or stroke in a lot of individuals.

Nevertheless, it has actually been revealed to raise blood pressure in several studies due to its stimulatory impact on the nervous system.

Raised high blood pressure is a risk aspect for cardiac arrest and stroke because it might damage arteries gradually, limiting the flow of blood to your heart and brain.

Thankfully, caffeine’s result on high blood pressure appears to be momentary. Likewise, it appears to have the greatest influence on individuals who aren’t used to consuming it.

High caffeine consumption has also been shown to raise blood pressure throughout exercise in healthy individuals, in addition to in those with slightly raised high blood pressure.

For that reason, taking note of the dose and timing of caffeine is important, particularly if you already have high blood pressure.

Rapid Heart Rate

The stimulatory effects of high caffeine intake might cause your heart to beat faster.

It may likewise lead to altered heartbeat rhythm, called atrial fibrillation, which has actually been reported in youths who took in energy beverages including very high dosages of caffeine.

In one case study, a lady who took an enormous dosage of caffeine powder and tablets in a tried suicide developed an extremely rapid heart rate, kidney failure and other severe health concerns.

Nevertheless, this effect does not appear to occur in everybody. Certainly, even some people with heart issues may have the ability to tolerate big amounts of caffeine without any negative results.

In one controlled research study, when 51 heart failure patients consumed 100 mg of caffeine per hour for 5 hours, their heart rates and rhythms remained normal.

No matter the mixed research study results, if you discover any modifications in your heart rate or rhythm after consuming caffeinated drinks, consider reducing your intake.


Coffee, tea and other caffeinated beverages are understood to improve energy levels.

Nevertheless, they can likewise have the opposite effect by leading to rebound fatigue after the caffeine leaves your system.

One review of 41 research studies found that although caffeinated energy beverages increased awareness and enhanced mood for numerous hours, participants were typically more worn out than usual the following day.

Naturally, if you continue to drink lots of caffeine throughout the day, you can avoid the rebound effect. On the other hand, this might impact your ability to sleep.

To take full advantage of caffeine’s advantages on energy and prevent rebound fatigue, consume it in moderate instead of high doses.

Regular Urination and Urgency

Increased urination is a common negative effects of high caffeine intake due to the compound’s stimulatory results on the bladder.

You may have observed that you require to urinate regularly when you consume more coffee or tea than normal.

Many research taking a look at the substance’s results on urinary frequency has actually focused on older individuals and those with overactive bladders or incontinence.

In one study, 12 young to middle-aged people with overactive bladders who took in 2 mg of caffeine per pound (4.5 mg per kilogram) of body weight daily experienced significant boosts in urinary frequency and seriousness.

For somebody weighing 150 pounds (68 kg), this would equate to about 300 mg of caffeine each day.

In addition, high consumption may increase the likelihood of developing incontinence in people with healthy bladders.

One big research study took a look at the effects of high caffeine consumption on incontinence in more than 65,000 ladies without incontinence.

Those who consumed more than 450 mg daily had a considerably increased risk of incontinence, compared to those who took in less than 150 mg per day.

If you drink a lot of caffeinated drinks and feel that your urination is more regular or urgent than it should be, it may be a great concept to cut down on your consumption to see if your symptoms enhance.

Ali Gadimov
Diet Expert