COFFEE TALK PART ONE: The Effects of Coffee on the Body

Let’s chat coffee. It’s delicious, feels like a cup of magic in the morning and it’s one of the most widely consumed substances in the world. I love it, 90% of people I know love it, and chances are you do too.

There are many articles out there that say drinking coffee can be beneficial to your health because it contains things like antioxidants and polyphenols (but you can also find these in fruit and veg) and some studies even show it may help prevent things like cancer, cardiovascular disease, depression, diabetes etc. When we read articles like these, it makes us feel good that our daily java habit isn’t as bad as we thought. But often these are quite one sided and don’t actually get into the nitty gritty on how caffeine affects the body as a whole.

But after having some health issues of my own which led me to the great coffee strike of 2018, I decided to do some unbiased research on coffee. I delved into the good, the bad and the downright fascinating effects of caffeine and came out the other side in awe of the information. Some things I already knew (but was in a little denial over) and things I didn’t know at all (like how it can change the brain’s chemical make up – say what?!).

Because there is so much interesting information I want to share with you, I’ll be breaking this up into a three part COFFEE TALK series:

  • Part One: The Effects of Coffee on the Body

  • Part Two: How to Break Up with Coffee

  • Part Three: 3 Coffee-Free Recipes to Start Your Day With

These will posted every Monday morning so make sure you tune in each week! Now let’s begin with Part One!

PART ONE: The Effects of Coffee on the Body

What happens when you drink it?

After that first glorious sip, the coffee travels down your gastrointestinal tract where the caffeine is then absorbed into the bloodstream. The maximum caffeine concentration in the blood is reached around the 60-90min mark post coffee. It has the ability to circulate all over the body, including the brain where it passes through the blood-brain barrier. It then travels to the liver to be metabolised and excreted.

How does it affect different parts of the body?

The Brain

We usually think of caffeine as a stimulant, and that’s why it keeps us awake and alert. But it’s a little bit more complicated than that. Caffeine is both water soluble (think blood) and fat soluble (think cell membranes), so it’s able to pass through the blood-brain barrier and straight into the brain. 

The structure of a caffeine molecule is very similar to that of Adenosine (a naturally occuring molecule in the brain) and because of this it can actually attach itself to the brain’s adenosine receptors, essentially blocking them off. Normally the adenosine would attach and make us feel tired, but with these receptors blocked off by caffeine, we don’t get that tired feeling for a few hours while the caffeine is still in our system and attached to those receptors.

There are also natural stimulants in the brain like Dopamine and Norepinephrine, that work more efficiently when the adenosine receptors are blocked. And when the body realises there’s lots of free adenosine floating around, the brain signals to the adrenal glands to produce Adrenaline to counteract it and adrenaline is yet again, another stimulant.

This is why drinking coffee has been shown to keep people awake and more alert, focused and attentive. It’s a combination of suppressing the body’s natural “tired signals” and allowing other stimulants to work more effectively in the process.

The incredible thing is with long term consumption of caffeine is the brain will produce more adenosine receptor sites to try and counteract the amount of caffeine we’re consuming. The more receptors there are, the more caffeine we have to consume to block them. This is why people develop a higher “tolerance” to caffeine, and find that they need more than one cup to feel that “buzz.” This is also another reason why coming off coffee can be so awful. Your brain gets used to a certain way of operating (for eg. with a larger number of adenosine receptors) and once you take away the daily dose of caffeine, it throws everything off causing things like the dreaded withdrawal headache we’ve all experienced at some point. But the body is resilient and coming off caffeine for even just a couple of weeks has been shown to reduce these receptor sites.


The live is incredible, it performs over 200 functions that are vital for our health. It is also our main organ for detoxifying the body and filtering and purifying blood. Like everything else, caffeine is metabolised in the liver. While the liver is an incredibly powerful organ, we need to consider all the things it has to deal with every day, like excreting hormones, toxins from exposure to things in the environment, harmful chemicals absorbed through the skin from the non-natural make up and body products we might use, and of course any sugar, alcohol and processed foods we might consume. Suddenly those two cups of coffee become part of a much larger picture of what needs to be processed and filtered, and when you look at it like that it’s easy to see why looking after the liver becomes so important.

Long story short, the less burden we put on it, the better it can do it’s job (which is ultimately to keep us healthy and toxin-free). While a cup or two is generally ok, if you’re looking into things like supporting detoxification/elimination, balancing your hormones, or improving the overall health of your liver, then it’s good to consider how reducing that burden on the liver looks like for you.


As mentioned above, the liver plays a big role in the body’s use of hormones. This includes those that naturally produced in the body, and synthetic hormones that are introduced into the body by things like the oral contraceptive pill. It acts like a processing plant for hormones, either manufacturing them, regulating them, directing them to their right jobs in the body or breaking them down and excreting them as waste.

When trying to re-balance your hormones (eg. to regulate your period, to assist with fertility or to help with menopausal symptoms), you want to be supporting the liver as much as possible so that’s it is doing it’s job as efficiently as possible to regulate your hormones. 


Caffeine stimulates the release of gastrin, which is a gastric hormone that speeds up digestion and transit time. It can also promote the release of bile and digestive enzymes. (So if you’re the kind of person that needs to go to the bathroom after a coffee, this is why!).

For a normal, healthy person this is not generally problem. But if you have digestive issues like IBS or leaky gut syndrome, or inflammatory conditions like IBD, Crohn’s or Ulcerative Collitis, it can exacerbate the symptoms and cause more problems for you.

Adrenal Health

You know how we were talking about how the brain signals for more Adrenaline to be released from the adrenal glands? Cortisol, our stress hormone, also gets released from these glands too. This also contributes to our much loved (but usually short lived) bursts of energy that we get when we drink coffee.

On occasion, this is fine for the body. But for people who are already over worked, constantly stressed, busy and run down, coffee is usually like a saviour to help them “push through” (it certainly has been for me in the past!). But doing this long term and having this continual release of adrenaline and cortisol is detrimental to the body and can lead to serious issues down the track like adrenal fatigue and complete burn out. This is exactly the time where you should be prioritising things like a good night’s sleep and some self care instead of having that extra coffee (easier said than done, I know).

If this has been interesting for you, make sure you check back in next Monday where I chat about when it’s a good time to have a break from coffee, as well as what to expect and how to reduce the withdrawal symptoms and my own personal experience with it so far!

What’s your relationship with coffee? How many cups do you have a day? And is it the taste, the comfort or the “buzz” you get from it that you love the most? Would love to hear from you in the comments below! (No judgement either – this is from one coffee lover to another!).


One comment

  1. […] you missed it, the first segment was Part One: The Effects of Coffee. Have a read through that first if you haven’t […]

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