Updated: Jan 30
together with some important strategies on how to maximise its health benefits
We all know coffee. Or at least we think we know it. We definitely drink it for its taste and its qualities. And how couldn’t we? Caffeine helps us focus and go through a long day, while being a good source of many protective compounds with antioxidant and anti-inflammatory proprieties.
Now that we have quickly established the known, let’s focus on the nuances of a beverage that never stops surprising both aficionados and researchers in regards to its ability to promote and support health.
But, there is a but and we will see together what strategies can help us enjoy coffee throughout life while maximising its benefits.
Epidemiological studies have followed cohort after cohort of individuals who consume coffee regularly and quite reliably have found astonishing associations between its use and a decreased risk of a constellation of diseases.
These associations seems to be precisely linked to the abovementioned compounds contained in coffee. For the nerds, the main compounds typical of coffee (apart from caffeine) are chlorogenic acids, cafestol and kahweol, trigonelline and melanoidins.
These names can sound strange and will be quickly forgotten by most of us, but the more we look into the mechanisms behind the potential benefits of consuming coffee, the more these molecules seem to be the key to understanding them.
Coffee consumption has been linked to a decreased risk of:
Stroke and heart disease
A multitude of liver illnesses
Type 2 diabetes
Both Alzheimer’s and Parkinson’s diseases
Overall mortality (the summation of all death causes, the gold standard in scientific literature)
These observations definitely represent a green light to coffee consumption and these protective compounds seem to be the reason, moreover in a recent review (a study of studies) even caffeine itself was linked to a decreased risk Parkinson's disease and type-2 diabetes.
Note: we have to keep in mind that these benefits are based on observations, not controlled trials, meaning that a precise causal relation between coffee and the positive health outcomes cannot be established. This being said, what we do know is that consumers of coffee seem to be more protected against a variety of negative health outcomes, and this is not a small thing!
Let’s now look at the but.
First a general premise: as with any food or beverage, it’s recommended that some people moderate their consumption. In particular children and adolescents, breastfeeding women and people with specific health conditions.
When discussing the buts, there are mainly two things to focus on: pregnancy and sleep.
In regards to pregnancy, the same review mentioned above and other studies registered association between caffeine consumption, low birth weight and increased pregnancy loss. Moreover caffeine may accumulate in oviductal or uterine fluid environments and induce epigenetic changes leading to adult-onset diseases in the newborn.
The precise mechanisms are not clearly defined, but there’s one important point we should remember:
In pregnant women caffeine’s metabolic rate is significantly decreased, especially after the first trimester. This means that the half-life of caffeine increases from 2.5–4.5 hours to approximately 15 hours, especially towards the end of pregnancy. In poor words, even a smaller amount of caffeine has a large effect during pregnancy.
What do we conclude from these data? Fortunately conclusions and guidelines are not our job, but the one of (way) more qualified institutions, such as The American College of Obstetricians and Gynecologists. Their official recommendation is that pregnant women should limit their daily caffeine intake to a maximum of 200 mg (equivalent cup of American coffee or two espressos).
As always, knowledge is power. Now that we know, we can make better choices.
We all want to be awake, alert and focused. And sometimes this is all we need, without compromise. But generally speaking, we also want to sleep well, rest, repair and consolidate memories. After all, our life is divided between these two phases: day and night.
On this note, while coffee can be a great tool during the day, we definitely want to prevent its stimulating effects to disturb the night. To understand how to do this we must peek into caffeine’s mechanism of action and extrapolate a simple take away.
Coffee keeps us awake in three ways:
Inhibiting the Cyclic AMP Phosphodiesterase pathway > this allows cells to “stay active” and stimulated for longer.
Activating noradrenaline neurons, acting on serotonin neurons and affecting the local release of dopamine > the experience is one of increased alertness, motivation and focus.
Acting as a competitive antagonist of Adenosine, a neurotransmitter that relaxes the brain and makes you feel tired > makes us feel steadily awake, even after a shorter night of sleep or late into the evening.
These interactions between caffeine and our physiology are the keys behind the ability of coffee to be the great tool we all appreciate and count on. But how to use it in a way that preserves our sleep and maximizes its positive potential for health?
We can start by trusting our internal perception. This will work well for the first two of these broad mechanisms and will take us a long way. In poor words: when caffeine is active in our system we feel more alert and awake and when these experiences start fading we can guess that caffeine’s effect is fading too, allowing us to unwind and go into restoring sleep.
Now we are left with the third mechanism, the one that involves adenosine. In this case our perception seems to fall short. The reason is that caffeine has a quarter life of 10 to 12 hours. This means that if we were to consume a cup of coffee at noon, a quarter of the caffeine contained in it would still be active in our system at 10 to 12 pm. Making this normal mid-day routine equal to drinking a quarter cup right before bed (if 10-12pm is your bedtime).
This doesn’t sound great, but many of us would stop and say “wait, I drink coffee way later in the day, sometimes even after dinner, and still fall asleep and then stay asleep without issues”…
Well this is the issue, our perception might not be very accurate in this case.
We know this because one experiment gave a cup of coffee to a group of individuals and registered a 20% drop in deep sleep even if they went to sleep and stayed asleep with no perceived issues.
Another study analyzed the sleep quality of people that were given one cup of coffee at 7.10 am and then abstained from drinking more during the day and found that their deep sleep had also dropped, but only by 10-12% (https://pubmed.ncbi.nlm.nih.gov/7796154/).
This teaches us two things:
Having caffeine active in the system when it’s time to bed can really matter, while at the same time being hard to feel.
Choosing to consciously time our coffee consumption and drink it in the morning will minimise its effect on our sleep that coming night.
This would allow for coffee to support our alertness and focus during that day while letting us sleep optimally at night. A win-win!
The take away
Coffee is something to be used and to be loved, but also to be known. Knowing coffee gives us the ability to enjoy it, while taking advantage of its potential for supporting and promoting health.
Coffee is popular for its stimulating effect, but researchers have shown its ability to contribute to health by being protective against a wide spectrum of chronic diseases.
We learned that pregnant women are much more sensitive to the effects of caffeine and should strongly limit their intake to avoid any complications.
We also learned that, if willing to maximize the health benefits of coffee, our perception might not be enough in regards to its interaction with sleep and that choosing to consume most of our coffee in the first part of the day can be a good strategy.