What Are The Side Effects of Too Much Caffeine (Part 2)

Here comes the second part of what are the side effects of having too much caffeine.

5. Addiction

Despite all of caffeine’s health benefits, there’s no denying that it may become habit-forming.

A detailed review suggests that although caffeine triggers certain brain chemicals similarly to the way cocaine and amphetamines do, it does not cause classic addiction the way these drugs do (30).

However, it may lead to psychological or physical dependency, especially at high dosages.

In one study, 16 people who typically consumed high, moderate or no caffeine took part in a word test after going without caffeine overnight. Only high caffeine users showed a bias for caffeine-related words and had strong caffeine cravings (31).

Additionally, the frequency of caffeine intake seems to play a role in dependency.

In another study, 213 caffeine users completed questionnaires after going 16 hours without consuming it. Daily users had greater increases in headaches, fatigue and other withdrawal symptoms than non-daily users (32).

Even though the compound does not seem to cause true addiction, if you regularly drink a lot of coffee or other caffeinated beverages, there’s a very good chance you may become dependent on its effects.

SUMMARY:Going without caffeine for several hours may lead to psychological or physical withdrawal symptoms in those who consume large amounts on a daily basis.

6. High Blood Pressure

Overall, caffeine doesn’t seem to increase the risk of heart disease or stroke in most people.

However, it has been shown to raise blood pressure in several studies due to its stimulatory effect on the nervous system (33343536).

Elevated blood pressure is a risk factor for heart attack and stroke because it may damage arteries over time, restricting the flow of blood to your heart and brain.

Fortunately, caffeine’s effect on blood pressure seems to be temporary. Also, it seems to have the strongest impact on people who aren’t used to consuming it.

High caffeine intake has also been shown to raise blood pressure during exercise in healthy people, as well as in those with mildly elevated blood pressure (3738).

Therefore, paying attention to the dosage and timing of caffeine is important, especially if you already have high blood pressure.

SUMMARY:Caffeine seems to raise blood pressure when consumed at high doses or prior to exercise, as well as in people who rarely consume it. But this effect may only be temporary, so it’s best to monitor your response.

7. Rapid Heart Rate

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

It may also lead to altered heartbeat rhythm, called atrial fibrillation, which has been reported in young people who consumed energy drinks containing extremely high doses of caffeine (39).

In one case study, a woman who took a massive dose of caffeine powder and tablets in an attempted suicide developed a very rapid heart rate, kidney failure and other serious health issues (40).

However, this effect doesn’t seem to occur in everyone. Indeed, even some people with heart problems may be able to tolerate large amounts of caffeine without any adverse effects.

In one controlled study, when 51 heart failure patients consumed 100 mg of caffeine per hour for five hours, their heart rates and rhythms remained normal (41).

Regardless of the mixed study results, if you notice any changes in your heart rate or rhythm after drinking caffeinated beverages, consider decreasing your intake.

SUMMARY:Large doses of caffeine may increase heart rate or rhythm in some people. These effects appear to vary greatly from person to person. If you feel them, consider reducing your intake.

8. Fatigue

Coffee, tea and other caffeinated beverages are known to boost energy levels.

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

One review of 41 studies found that although caffeinated energy drinks increased alertness and improved mood for several hours, participants were often more tired than usual the following day (42).

Of course, if you continue to drink lots of caffeine throughout the day, you can avoid the rebound effect. On the other hand, this may affect your ability to sleep.

To maximize caffeine’s benefits on energy and avoid rebound fatigue, consume it in moderate rather than high doses.

SUMMARY:Although caffeine provides energy, it can indirectly lead to fatigue when its effects wear off. Aim for moderate caffeine intake to help minimize rebound fatigue.

9. Frequent Urination and Urgency

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

You may have noticed that you need to urinate frequently when you drink more coffee or tea than usual.

Most research looking at the compound’s effects on urinary frequency has focused on older people and those with overactive bladders or incontinence (434445).

In one study, 12 young to middle-aged people with overactive bladders who consumed 2 mg of caffeine per pound (4.5 mg per kilogram) of body weight daily experienced significant increases in urinary frequency and urgency (44).

For someone weighing 150 pounds (58 kg), this would equate to about 300 mg of caffeine per day.

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

One large study looked at the effects of high caffeine intake on incontinence in more than 65,000 women without incontinence.

Those who consumed more than 450 mg daily had a significantly increased risk of incontinence, compared to those who consumed less than 150 mg per day (45).

If you drink a lot of caffeinated beverages and feel that your urination is more frequent or urgent than it should be, it may be a good idea to cut back on your intake to see if your symptoms improve.

SUMMARY:High caffeine intake has been linked to increased urinary frequency and urgency in several studies. Reducing your intake may improve these symptoms.

Hence, light-to-moderate caffeine intake seems to provide impressive health benefits in many people. On the other hand, very high dosages may lead to side effects that interfere with day-to-day living and might even cause serious health issues. Although responses vary from person to person, the effects of high intake demonstrate that more isn’t necessarily better. To get the benefits of caffeine without undesirable effects, conduct an honest assessment of your sleep, energy levels and other factors that might be affected, and reduce your intake if needed

Source from: Healthline, Written by Franziska Spritzler, RD, CDE

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