Updated: Nov 8
Full disclosure – this is not a simple nor straightforward discussion. The evidence is very mixed, and even taking that into account, we are all very individual, which has a massive effect on whether coffee benefits you personally.
After a cup of coffee, most people will notice an effect within 15-20 minutes, taking longer if we have something to eat simultaneously. It is then processed by enzymes in the liver. How fast this happens depends on genetics, race, tolerance, smoking, and some medications.
Smoking increases the rate at which we get rid of caffeine, and the oral contraceptive pill slows it down, as does alcohol.
My genes process caffeine slowly, which means it may take me 8 hours to get rid of HALF the caffeine in my cup of coffee.
Coffee contains many chemicals; polyphenols are the most important or well-known. Research suggests these have several health benefits, including reducing inflammation, improving insulin sensitivity, protecting your liver, and possibly helping with gallstones.
Coffee drinkers tend to have a more varied microbiome (the bacteria in your stomach).
Overall, variety in your gut is viewed as better for your health. The actual reason for this improved variety is unknown, possibly due to the polyphenols but also because the coffee contains quite a bit of soluble fiber. Soluble fiber can feed and nourish the microbiome. It can also help lower cholesterol levels, which, when combined with the reduction in inflammation, means that coffee can be good for heart health.
Coffee improves bowel regularity.
Many people need to go to the bathroom within 30 minutes of drinking coffee. So it can be helpful if you suffer from constipation.
For some people, caffeine may improve (i.e., speed up) your metabolism.
This is dependent on the dose, and sadly, it is likely that you will become tolerant to this effect.
It improves alertness, sustained attention, and possibly mood.
This is a long list.
For me, the two most significant issues are the impact on your stress response system and the impact on sleep.
Stress Response System
Caffeine is a stimulant that will kick your brain to produce the chemicals associated with stress; adrenaline and cortisol.
The upside of this is the increase and alertness; the downside can be palpitations, anxiety, restlessness, and your adrenal glands having a hard time (because they are stimulated to produce more cortisol and adrenaline).
This can be particularly problematic during menopause since your adrenal glands become the primary source for making sex hormones. The path to making progesterone is linked to cortisol. So if we are being pushed to make more cortisol, we will produce less progesterone, and the balance with oestrogen then tends to go AWOL.
Cortisol will stimulate an increase in blood sugar levels.
The body will then have to try and regain control, so we are much more likely to end up with the detrimental roller coaster blood sugar ride. This can impact type 2 diabetes and many menopause symptoms.
During the day, we produce a chemical called adenosine. Adenosine has many functions, one of which is connected to sleep. It accumulates, and we start to feel sleepy when we reach a certain level. While we sleep, the levels decrease, and we restart this process all over again when we wake up.
Caffeine blocks this action; it inhibits adenosine and increases wakefulness. If you process caffeine slowly, it will hang around much longer, stopping this gradual and natural sleep kick. Top that with the general stimulatory effect, it is no wonder that caffeine can have a massive impact on insomnia.
Caffeine is a diuretic.
This means it increases the production of urine. You have probably worked that out – how many times after drinking a cup do you rapidly need to pee. This can sometimes affect our skin through dehydration – so it is essential to drink plenty of water to avoid those wrinkles. This process can also lead to a depletion of some vitamins and minerals.
Caffeine can also reduce the absorption of both calcium and iron.
How significant this is, is debatable – possibly more so with the iron absorption.
Coffee is a bladder irritant.
If you suffer from UTIs and similar symptoms, it is worth giving it a miss for a while.
Coffee is one of the most intensively sprayed crops in the world. It needs large amounts of pesticides, herbicides, fungicides, and chemical fertilizers to achieve maximum production. Add to these, chemicals used in the roasting process, in coffee bags and packaging, and in the process to remove caffeine.
This is not a problem for many people, but it can be if you are sensitive to mold (as I am) or your liver is struggling. I always recommend that people look at how 'clean' their coffee is, especially when drinking several cups daily.
The effect on the stomach is not only limited to being a laxative. Coffee can trigger acid reflux and irritate ulcers.
Caffeine can alter oestrogen metabolism – the result of this, possibly particularly during perimenopause when your progesterone reduces first, is breast tenderness.
Only you can work out the balance of the pros and cons. I like drinking coffee, but I follow an assortment of guidelines.
I absolutely never drink coffee after 12 midday, and in an ideal world, not after 11am.
I don't drink it on an empty stomach so that I reduce the rate at which it is absorbed. Drinking it with cream is another possibility.
I look at how my coffee is made, even the decaffeinated stuff, to reduce the toxins that come with it.
I go through phases of drinking the chicory stuff – sometimes I like it, other times not.
I limit my intake of all caffeinated drinks, including regular and green tea.
If my stress levels are particularly high or I feel' hormonal', I skip it.
Other things that you can do to help mitigate any problems include.
Exercise after drinking coffee or any other caffeinated drink; exercise speeds up its metabolism.
Look at what you are consuming. Energy drinks can contain a vast amount of caffeine and sugar, which can be a disaster.