“Without my morning coffee, I’m just like a dried-up piece of roast goat.” – Johann Sebastian Bach
We are fed the idea that coffee is essential to our morning routines. Whether it boosts alertness or
nudges nature’s call, coffee is now a global commodity as well as a social and business lubricant.
If you’re still reading, you probably think that coffee is a beverage with which you have an intimate
relationship. You’re not alone. With 2.5 billion cups drunk daily, only water surpasses coffee as the
beverage of choice worldwide.
Studying the effects of coffee is particularly challenging. Isolating for a beverage with over 1000
compounds is so tricky that all studies tend to be population effect studies or literary reviews. These can
show general trends, but when trying to isolate for serious disease prevention, the results are
associations, rather than causal.
Improvements in isolation techniques have, however, helped scientists dive deeper into the ways
certain coffee compounds are affected by the way we prepare our coffee, and how the time of
consumption creates the effects we know.
The Global Health Drink.
Kim Y, eta al (2019) show coffee consumed at the rate of 3 to 4 cups (80-100mg of caffeine each) daily
does reduce all-cause mortality, regardless of other mortality factors, such as weight, drinking alcohol,
and smoking. At these consumption levels, coffee is even safe for those with hypertension and high
blood pressure. Meta-analyses and literature reviews show that coffee consumption benefits the full
range of cardiovascular health, cognitive disorders, diabetes, Alzheimer’s, inflammation, cancer, and
heart disease. With its prevalence in societies globally, and the health benefits documented in the last
eight years, it is certain that few beverages will continue to be studied as thoroughly as coffee.
The Diabetes Exception
Yang et al (2024) studied the effects of coffee and tea drinking on 5380 people being treated for
diabetes and found that consuming coffee between dawn and noon elevated their risk of death from
cardiovascular diseases, while forenoon to noon showed a reduced risk. If you’re diabetic and reading
this, please refer to the detailed study, linked in the reference list below, and consult your health care
professional.
Extracting the Benefits
To gain the benefits of coffee-drinking, how it is roasted and brewed are more important than whether
you’re using organic or conventional beans. Differences do exist, but they pale when compared to the
handling and preparation methods. Using a medium roast and brewing it for three minutes is the most
effective way to extract its beneficial compounds. This is most commonly achieved by using what is
known as a French press, although the majority of benefits remain regardless of brewing technique.
Decaffeinated coffee demonstrates the same health outcomes. Caffeine itself is not associated with the
many health benefits uncovered in the research, and non-coffee caffeinated beverages will not confer
most of the benefits of the 1000+ compounds found in coffee.
Health benefits and Time of Day Consumption.
All-day coffee drinkers experience fewer health benefits than morning drinkers, possibly because they
are more likely to ingest more than the recommended four cups a day, beyond which benefits are
reduced, and negative effects emerge.
“I don’t really like coffee…but I don’t really like it when my head hits my desk when I fall asleep either.”
– Brian Andreas
Performance, Circadian Rhythms and Coffee.
Is there a difference in these health outcomes, and performance outcomes depending on when coffee is
consumed?
While it doesn’t play a role in the health benefits of coffee-drinking, caffeine is a driver of sports
performance. Zhang et al (2024) show seventy-six percent of athletes have blood caffeine readings that
reinforce the same survey data, indicating caffeine’s use as a performance enhancer. The effects peak
after 30-90 minutes from consumption. The research shows that mornings are typically the lowest
athletic performance windows, caffeine has a greater effect on our abilities at these times.
And it’s not just athletes who benefit. Morning caffeine consumption reduces fatigue and extends our
afternoon alertness for everyone, including students. But afternoon consumption does not further
extend these benefits.
Our circadian cycles are approximately 24 hours (24.09 h for women and 24.19 h for men). Rhythms
during the cycle vary from person to person and are affected by temperature and lifestyle patterns.
Afternoons, when our body temperature is at its peak, is also the time when our sports performance is
at its peak. Caffeine has an effect here, by reducing the decline in morning sports performance, with
regular slow dose caffeine intake reducing the effect of sleep deprivation. This means that caffeine
taken in the morning not only reduces the effects of sleep deprivation (for example, pre-event nerves),
but carries its benefits through to the peak performance period of afternoons.
“Coffee is a way of stealing time that should by rights belong to your older self.” – Terry Pratchett
Not for You? You’re Not Alone.
One third of athletes claim that caffeine has either no or a deleterious effect on their performance.
To Male Readers – Sorry, No.
Despite many attempts by researchers to find statistical causation, there is no reliable evidence that
coffee plays a role in libido or sexual performance in men.
Memories
The morning is when our memory function peaks, with a slow slide to the “where was I?” afternoon
slump. Caffeine in the morning has been shown to prolong the morning memory function and largely
avoid the afternoon slump.
More is Less
Drinking more than four cups a day has not shown any increased benefit and, in fact, may even increase
risk. Alzheimer’s disease risks increase, as do bone density reductions (especially for women) and
resultant fractures. High doses are associated with higher risks of cardiovascular complications.
Coming Down
It can take up to 10 days to entirely eliminate the withdrawal symptoms of caffeine, which can go
beyond the headaches and lethargy to actual depression.
Conclusion
Drinking coffee in the morning has benefits for memory and performance that typically last through the
afternoon and are not increased by afternoon consumption. The health benefits of drinking up to four
cups of coffee a day are significant, regardless of time of consumption.
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