The Effects of Caffeine on Your Body

You're here because you want to learn about the effects of caffeine, right? I'm sure you already have a hunch that caffeine is not all that good for you, so it would be really great to know how caffeine affects the body... how does it work and why is it a bad thing? Well, let's get right to the point then:

Effects of caffeine

Caffeine is, along with nicotine and alcohol, one of the most widely used mood-affecting drugs in the world. It produces a response similar to the stress response in our bodies, but affects each person differently. For instance, it may cause some people to stay awake, but help induce sleep in others...very strange, I know!

Caffeine is very addictive! It is a central nervous system stimulant which temporarily keeps us more awake and alert. It acts as a diuretic which means that it draws water from the body, so you may feel the need to go to the loo more often.

In order to understand the effects of caffeine, particularly the side effects more clearly, it may be useful to click on this link to learn about “how does caffeine work?”

A regular caffeine drinker’s body adapts to having caffeine all the time. It has to produce more adenosine, which is a brain chemical which stops the release of our natural stimulants, dopamine and adrenalin. What happens then is that when we don’t get our caffeine fix, we feel anxious, tired and unable to cope. This starts a vicious cycle which can have some serious health effects. It is interesting to know that as little as 100mg of caffeine a day - which is about 1 cup of coffee – is enough to cause withdrawal symptoms when we stop drinking caffeine.

Some of the more common caffeine side effects are:

  • increased heart rate
  • feeling of being jittery and nervous
  • headache
  • difficulty sleeping
  • increased blood pressure
  • difficulty concentrating
  • more frequent urination
For a more detailed look at the side effects, please see my “caffeine side effects” page.

The Effects of Caffeine on Children

Caffeine has the same side effects on children as it does on adults, only they are smaller and lighter than adults, so caffeine will have a more intense affect on them. In other words, drinking only a small amount of a caffeinated drink will have much more of an effect than it will on an adult.

Children around the world love cola drinks, but often we don't realise that they are quite high in caffeine - which is hidden in quite a number of popular dinks today.

It is highly advisable for children to avoid such drinks as studies have shown that it causes them to be more restless and hyperactive – so much so that the hyperactivity level is enough to meet the criteria for attention deficit disorder with hyperactivity (ADHD). Another study showed that children deprived of their daily intake had trouble thinking clearly, were lethargic and tended to get angry more often.

The effects of caffeine

Common Sources of Caffeine

Here is a handy table with some of the more common sources of caffeine. You can see approximately how much caffeine each item contains. Please note these amounts are not exact and will vary.

ProductServing SizeCaffeine Content
Regular Coca-Cola350ml (12fl oz)46mg
Diet Coke350ml (12fl oz)46mg
Mountain Dew350ml (12fl oz)55mg
Pepsi350ml (12fl oz)38mg
7-Up350ml (12fl oz)0mg
Red Bull150ml (5fl oz)80mg
Instant Coffee150ml (5fl oz)40-105mg
Filter Coffee150ml (5fl oz)110-150mg
Espresso, Latte, Cappuccino150ml (5fl oz)30-50mg
Starbucks Coffee (grande)350ml (12fl oz)500mg
Decaf Coffee150ml (5fl oz)0.3mg
Black Tea150ml (5fl oz)20-100mg
Green Tea150ml (5fl oz)20-30mg
Hot Chocolate150ml (5fl oz)10mg
Dark Chocolate28g5-35mg
Milk Chocolate28g6mg
Chocolate Cake1 slice20-30mg
Caffeine Tablet – regular strength1 tablet100mg
Cold Relief Tablet1 tablet30mg

If you would like to learn more about the caffeine in coffee and tea, please click on this link.

Can Caffeine Have Positive Effects?

There is research out there that suggests that coffee may have some positive health effects, saying that caffeine may protect us against:

  • Parkinson’s disease – in men only. The studies in woman have been inconclusive
  • Type 2 diabetes
  • Liver cancer
  • Liver cirrhosis
  • Heart disease
This may be good news if you love drinking coffee, but the research is not at the stage where you could say that you should drink coffee to increase your health. Personally, I think that it is not advisable to drink more than 2 cups of coffee a day, although no more than 1 cup of coffee, 2 cups of black tea or 3 cups of green tea is ideal. Drinking any more than that starts to put strain on your liver.

Many people, in an effort to improve health, cut out coffee even though they really enjoy it, but studies suggest that focussing on good nutrition, exercise and not smoking are far more beneficial for improving overall health and well-being.So it seems that for most people, besides pregnant woman and people who have trouble controlling their blood sugar or blood pressure, coffee isn’t such a bad beverage choice for adults after all… but moderation is the absolute key.

What Does Your Cup of Coffee
Mean to You?

There is an ongoing debate about coffee: should you drink it or shouldn't you, or how much is ok to drink! For so many, coffee is more than just a warm drink.

Why not tell us what your cup of coffee means to you and why you love it so much.

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I do hope you found this information about the effects of caffeine interesting and helpul in your quest for good health. If you have any questions or comments in relation to facts about caffeine, please contact me as I would love to hear from you.

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