Caffeine myth-busting for coffee lovers
Is caffeine bad for your health, and does all decaf taste bad? A nutritionist and barista offer their verdicts on some controversial claims about coffee.
Coffee and caffeine are two sides of the same bean: for many drinkers, the effects of caffeine are just as alluring as the taste of a tongue-tingling espresso or complex cold brew. Even decaf coffee is defined against the stimulant, and the word ‘caffeine’ is derived from café, which is French for ‘coffee’.
I’m a daily coffee drinker, and while I consume less caffeine than some, my regular short blacks to-go and moka pot brews at home add up. The habit hasn’t been without its drawbacks: sometimes, I’ve struggled to sleep after drinking coffee too late in the day, and an excess of caffeine seems to make me feel jittery.
But, then again, don’t we all feel unusually lively or anxious from time to time? It’s tricky to isolate the effects of caffeine from other influences on the mind and body, and perhaps this is why there are lots of contradictory claims about coffee and the compound it contains.
To bring some clarity on caffeine and its effects, I interviewed Holly Dunn, a nutritionist who recently ran a literature review on coffee, and Seb Wilkey, head barista at Holding Patterns listening bar in Leeds, to establish which popular claims about caffeine are true and which are a steaming mug of myth.
They say: caffeine gives you energy
It’s often said that caffeine gives you energy, but that’s not quite what this compound does to us.
While we do things and expend energy during the day, a natural compound called adenosine builds up in the brain. We have structures called adenosine receptors that identify the chemical and cause us to feel sleepy.
Caffeine blocks these adenosine receptors, so we tend not to feel as sleepy after a cup of coffee or caffeinated drink.
We say: caffeine doesn’t give you energy, but rather reduces the urge to sleep.
They say: coffee and caffeine are bad for you
“How 'good' or 'bad' coffee is for you will always depend on contextual factors, such as when, how and how much you drink it,” says nutritionist Holly Dunn.
“The effects also vary with individual factors, such as your genetic makeup, age, hormones and pregnancy, your general health and whether you take any medications. Even your gut microbiota play a part.”
One health harm that seems common among moderate-to-heavy coffee drinkers (those who consume over 400mg of caffeine per day) is increased anxiety.
“This is because caffeine hinders an inhibitory neurotransmitter in the brain, leading to increased nervous system stimulation, resulting in anxiety, jitteriness and sleep disturbance (for up to 8-12 hours after consuming),” says Dunn.
“Some people might also experience increased heart rate, headaches, digestive issues and other complications, and it’s generally recommended to avoid coffee and other caffeinated drinks during pregnancy, or at least limit your caffeine intake to 200mg or less per day.”
We say: studies have shown potential health downsides to coffee and caffeine consumption, especially increased anxiety and troubled sleep, but the effects vary depending on factors like your coffee drinking habits and overall health.
They say: coffee is good for you
Can drinking coffee improve your health? Dunn says that certain advantages have been shown to exist: “There are benefits associated with coffee’s anti-inflammatory, anti-diabetic, antioxidant, prebiotic, neuroprotective and performance-enhancing properties.
“In fact, systematic reviews and high-quality research consistently report inverse associations between coffee consumption and all causes of death, including several cancers and cardiometabolic disease. Based on this research, it is thought that around three cups of coffee per day may have measurable benefits for our health.”
While coffee’s apparent performance-related benefits are linked specifically to its caffeine content, other health benefits are rooted in its broader nutritional content.
“Coffee has a complex nutritional composition, comprising over a thousand bioactive compounds with the potential to influence our health and performance, including polyphenols and other secondary metabolites,” says Dunn.
“It’s also a source of micronutrients, including potassium, vitamins B3 and E, and a potentially important source of magnesium in modern societies, with one serving covering 6.4-7.5% of the daily requirement for men and women, respectively.”
We say: coffee has clearly been shown to have health benefits. Some of these are linked to caffeine, but most appear to stem from other plant compounds, such as polyphenols.
They say: all decaf coffee tastes bad
“I think decaf used to taste worse,” says Seb Wilkey, head barista at Holding Patterns.
“The original decaffeination process used benzene as a solvent, which degraded the taste and is now known to be carcinogenic.
“The methods now used, such as the Swiss water process, are both health-conscious and preserve the flavour of the coffee bean. They use a green coffee extract to achieve a full coffee flavour with very little caffeine.
“Decaf no longer has to be something bitter and horrible that people that would drink begrudgingly. Now, you have companies that can extract and put it through the more experimental processes caffeinated beans go through as well, so you can still have insane fruit flavours with 0.1% of the normal caffeine.”
If you’re aiming to reduce your caffeine intake but don’t need to cut it out completely, Wilkey suggests exploring the growing array of low-caff coffees now available: “I recommend two low-caffeine varietals in particular: aramosa, a cross-breed with 50% less caffeine than your typical bean, and laurina, which is grown in Yemen and has a natural mutation in the caffeine synthase of the bean, which reduces the content.
“Different roasters are starting to do half-caff blends with both low-caff and decaf beans to create a drink that a lot of people are moving towards.”
We say: decaf used to be considered worse-tasting than regular coffee, but improved decaffeination methods have allowed more flavourful decafs to emerge.
They say: coffee should be hot
The conventional wisdom is that coffee should be served hot. While preferences vary, the ideal brewing temperature for an espresso is generally given as somewhere between 90-96C.
However, cold-brew coffee is fast becoming a popular alternative among coffee lovers, and according to Wilkey, it offers some distinct benefits: “People in the UK used to want their coffee piping hot, but now with the rise of specialty coffees, producers are recommending we brew at lower temperatures to preserve the flavours of the coffee beans.
“You can prepare coffee via cold brewing – a pure immersion technique – using something like a toddy, or you can use a cold drip tower filled with ice and cold water, which drips from 6-12 hours to bring out a full-bodied flavour with a slightly different (and generally sweeter) profile to hot coffee.”
We say: hot coffee is still a treat, but lower-temperature preparation techniques, such as cold brewing, can produce a different flavour profile.
They say: caffeine is addictive
The evidence suggests that it’s certainly possible to become dependent on caffeine, both physically and psychologically.
“This dependence is often linked to caffeine’s perceived ability to increase energy and physical performance, as well as alertness, and focus,” says Dunn.
“Regular caffeine consumption can also lead to withdrawal symptoms like headache, low mood and fatigue if stopped abruptly. However, it is important to recognise that caffeine creates a false sense of energy, rather than providing actual energy to the body.”
Keeping your coffee consumption moderate should help reduce your risk of developing a dependency.
“For healthy adults, a safe upper limit for daily caffeine consumption is generally considered to be 400mg, lowering to 200mg in pregnancy. For my female clients wishing to conceive, I also usually advise observing the upper limit for pregnancy,” says Dunn.
“However, these suggested limits may be much lower in sensitive individuals, so it's always important to listen to your body. 400mg of caffeine equates to approximately four 200ml cups of instant coffee, two 200ml cups of filter coffee, or four to six cups of tea per day. It's also worth bearing in mind that the caffeine content of barista coffees can vary hugely, with a medium Costa cappuccino containing as much as 325mg caffeine.”
We say: caffeine can be addictive, but the risk of dependency can be managed by keeping your intake moderate.
Further reading:
Everything you need to make barista-quality coffee at home, from beginner to enthusiast
10 of the best coffee subscriptions to order online
How to keep your coffee beans fresher for longer
When is the best time to drink coffee?
Is coffee good for you?
All health content on goodfood.com is provided for general information only, and should not be treated as a substitute for the medical advice of your own doctor or any other health care professional. If you have any concerns about your general health, you should contact your local health care provider. See our website terms and conditions for more information.
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