Decaf: Health Upgrade or Hidden Risk?
The surprising science behind a small decision with big consequences.
For the last year or so, I’ve mostly switched to decaffeinated tea. It started in the evenings, a gentle wind-down, but soon became a full-time habit. I still have my lunchtime full-strength coffee to fend off that mid-afternoon slump, but otherwise, it’s decaf all the way.
I’m a happy tea and coffee drinker, not just for the flavour and comfort, but because science says they’re good for us.
But lately, I’ve been wondering if switching to decaffeinated might be shooting myself in the foot.
Two things have been bothering me:
When manufacturers take out the caffeine, do they strip out all the good stuff too - the polyphenols, the antioxidants?
And what about the chemicals they use to get it out in the first place - are we sure they’re safe?
Actually, there’s a third concern - microplastics in tea bags - but we’ll park that one for another time.
Today I thought to myself, how about if you stop wondering and find out?
So that’s what I did.
And what I found surprised me: the right kind of decaf might actually reduce anxiety, improve sleep, and even lower the risk of serious falls, while the wrong kind could leave behind residues of a solvent so toxic it’s been banned in paint strippers.
Let’s unpack what decaffeination does to your brew - and potentially to you.
Why should we care about decaffeinated tea and coffee?
Once upon a time, decaf drinkers were seen as a niche tribe - the kind of people who wore sandals, hugged trees, and shunned caffeine on principle.
If that’s still your mental image, it’s time for an update.
Decaf is having a quiet revolution. And not just among older adults. Younger consumers, millennials and Gen Z are leading the shift. Some surveys suggest up to 30% of coffee drinkers now choose decaf at least some of the time. For tea, UK figures suggest 15–20% of Brits drink the decaffeinated stuff regularly.
Why the shift?
It’s not just about avoiding the jitters. More people are realising that caffeine can interfere with sleep, increase anxiety, and irritate the bladder, especially if you’re prone to overactive bladder or frequent nighttime trips to the loo.
What made me sit up was this: switching to decaf didn’t just help people sleep - it helped prevent injuries and likely saved lives.
In nursing homes across two UK regions, simply switching residents to decaffeinated tea and coffee led to a 30–35% drop in falls.
Not because decaf made them steadier, but because they were no longer rushing to the toilet.
When you realise that around a third of older adults die within twelve months of a hip fracture, it’s not hyperbole to say: decaf can save lives.
As our population ages, and more people manage sleep issues, urinary frequency, and frailty, this becomes a much bigger public health question than it might first appear.
So, whether you drink it now or not, chances are you, or someone you care about, will be drinking more decaf in the future.
All the more reason to understand how it’s made - and whether some types are safer than others.
How are tea and coffee decaffeinated?
There are three main methods for removing caffeine from tea and coffee. They vary not just in chemistry, but in how much of the original flavour they preserve - and what they leave behind.
Solvent-based extraction
Tea leaves or green coffee beans are first steamed and then rinsed with a chemical solvent, typically methylene chloride or ethyl acetate, that binds to caffeine. The solvent, now carrying the caffeine, is removed from the beans or leaves and processed separately to recover it, leaving the original tea or coffee much lower in caffeine.
Water-based extraction
Caffeine can also be removed using only water and heat. In coffee, this is often called the Swiss Water Process. Sadly, it doesn’t involve Swiss glacier water (probably just as well, given how fast they’re melting). While it was invented in Switzerland, most Swiss Water coffee is now processed in Canada, but the name stuck, likely because both Switzerland and water sound reassuringly clean. Tea also uses water-based methods, though they tend to be simpler and less standardised.
Supercritical CO₂ extraction
This method uses carbon dioxide - not the fizzy kind, but CO₂ under high pressure, where it behaves like both a gas and a liquid. It sounds like something that should involve hazmat suits and a panic button, but it’s actually a clean, efficient way to extract caffeine while preserving flavour. It’s especially common in Europe, where solvent use is more tightly regulated.
Bonus fact: The caffeine removed from your coffee doesn’t go to waste.
It’s filtered, dried into a fine white powder, and resold - mostly to the energy drink and pharmaceutical industries. Some ends up in pre-workout powders, weight-loss pills, and even cosmetics.
That little lift in your can of Red Bull or Excedrin? It might just have started life in someone else’s morning coffee.
Is decaffeination safe?
If your tea or coffee has been decaffeinated using either water or CO₂, you can pour without a second thought.
These methods are clean, effective, and leave no detectable residue. I drink both happily.
It’s the solvent-based methods that deserve closer inspection.
Most use either ethyl acetate or methylene chloride. Their risks are very different.
Ethyl acetate: the “natural” solvent
Ethyl acetate is an ester with a sweet, fruity smell that reminds many people of pear drops as it's used in confectionery, though some say it smells more like nail polish remover or glue!
It’s rapidly broken down in the body into ethanol and acetic acid, and at the trace levels found in food, it’s not considered harmful. At industrial levels, it can cause irritation to eyes and airways, but that’s a concern for factory safety, not your morning brew.
Because ethyl acetate can be derived from sugarcane or fruit, products processed with it are often marketed as “naturally decaffeinated” or “sugarcane decaf.” That sounds wholesome, though in reality it's marketing speak; most ethyl acetate is made synthetically.
Still, there’s little here to worry about.
Methylene chloride: a different story
Methylene chloride is another solvent entirely - and it’s highly toxic.
As little as a tablespoon can be fatal. It vaporises easily, making it dangerous to inhale. Exposure can cause confusion, fatigue, headache, chest pain, and even death due to its effects on the central nervous system. It’s also thought likely to be carcinogenic.
Between 1980 and 2018, at least 85 deaths were linked to methylene chloride exposure in the US.
I used to keep a tin of it under the sink. Back then, it was a go-to paint stripper - cheap, potent, and sold in every DIY shop. If this article were scratch-and-sniff, I suspect many of you would recognise the smell. People died using it in garages, bathrooms, and basements.
And yes - it’s still used to decaffeinate tea and coffee.
Regulated, but still in your morning brew
Manufacturers insist the trace residues in decaffeinated drinks are well below established safety limits. That may be true.
But personally, I find it hard to feel reassured by “just a little bit” of a known toxin and suspected carcinogen.
The US EPA banned most industrial uses of methylene chloride in 2024, calling it a “dangerous chemical” that has "devastated families across this country for too long".
But that didn’t touch food production. That falls under FDA jurisdiction, and while several petitions have called for a ban in food manufacturing, the FDA has yet to act.
In contrast, Europe regulates more strictly, so CO₂ and water-based methods predominate.
Estimates suggest around 60% of decaffeinated tea and coffee sold in the US is still made using solvents, likely with methylene chloride as the agent.
To make matters worse, solvent-based decaffeination doesn’t just raise concerns about residue, it’s also more likely to strip out beneficial compounds like polyphenols and antioxidants.
So what can we do?
If you see Swiss Water or CO₂ processed on the label, great - those are safe choices.
Ethyl acetate isn’t worrisome either, and some people even enjoy the subtle fruity flavour it leaves behind.
It’s methylene chloride I’d avoid. Officially “safe,” at least in the US, but still questionable enough that the EPA banned its use in paint. That’s not something I want in my mug.
Finding out what you’re drinking
Most brands don’t tell you how their tea or coffee is decaffeinated, but some do, and it’s worth paying attention. Here’s what I’ve found:
Direct from manufacturers:
The Swiss Water company lists dozens of brands using its process.
Twinings Everyday Decaffeinated and Tetley use ethyl acetate.
Teapigs and The UK Loose Leaf Tea Company use CO₂.
Based on tea/coffee community reports (unverified):
The Clean Label Project lets you check your decaf coffee and discover which method is used (though I've noticed some discrepancies on different pages).
Thompson's, Clipper Organic, Cornish Tea, and Taylors use CO₂.
Barry’s Tea, Yorkshire Tea, PG Tips, Typhoo, Marks & Spencer, Bewley’s, Welsh Brew, Birchall, King Cole, and Miles use methylene chloride.
If your usual brand doesn’t say, that’s a clue in itself.
Now that we’ve looked at safety, the final question is this:
When we remove the caffeine, do we also lose the good stuff - the antioxidants and polyphenols that make tea and coffee worth drinking in the first place?
Let’s find out.
Does decaffeination remove beneficial compounds along with caffeine?
In an ideal world, decaffeination would remove only the caffeine - leaving behind all the good stuff: the antioxidants, polyphenols, and flavour molecules that make tea and coffee worth drinking in the first place.
But what actually happens?
Coffee: Good news
If you’re a coffee drinker, this graph brings good news.
Supercritical CO₂ and Swiss water processing both reduce caffeine by over 90%, while preserving the antioxidant alkaloid trigonelline and a range of polyphenols. Some even increase after decaffeination.
A separate study using the Swiss water method found that decaffeinated coffee had higher antioxidant activity than regular coffee.
If you're serious about maximising antioxidants, focus less on decaffeination and more on roast level and brew method, but that’s a conversation for another time.
Tea: A tale of two leaves
A detailed study by the Tea Research Institute in Chongqing, China, found that supercritical CO₂ decaffeination affects black and green tea very differently.
For green tea, around two-thirds of the polyphenols were lost.
For black tea, polyphenol levels stayed almost unchanged.
It also altered the flavour profiles:
Decaffeinated black tea became less bitter and more floral. Most tasters actually preferred it to the original.
Decaffeinated green tea also lost some of its bitterness, but had enhanced umami and sweetness. Tasters preferred the regular version.
The takeaway?
If you’re drinking decaf for the health benefits:
Coffee holds up well, especially with Swiss Water or CO₂ processing.
Black tea is a solid choice - polyphenols stay intact, and the flavour may even improve.
Green tea loses much of its benefit, and its distinctive taste.
Now that we know how decaf affects both safety and health value, let’s tie it all together.
HEALTH TWEAK OF THE WEEK ☕
If you drink decaf, make sure it’s the right kind.
Decaffeinated tea and coffee have come a long way. The days of bitter brews made from low-grade leaves and beans are fading. As demand grows, so does quality.
And switching can bring real health benefits:
💤 Better sleep
😰 Less anxiety
💥 Fewer headaches and crashes
🚽 Fewer urgent bathroom trips
That last one matters more than you think. In older adults, simply swapping to decaf reduced falls by up to 35% because they weren’t rushing to the toilet as often. That’s not just a comfort issue. One in three people dies within 12 months of a hip fracture.
But not all decaf is equal.
Some methods leave behind nothing but flavour. Others leave traces of solvents - including methylene chloride, a likely carcinogen banned for use in paint strippers.
Here’s how to choose well:
✅ Swiss Water or CO₂-extracted = safest options.
✅ Ethyl acetate is also considered safe, though some notice a fruity taste.
❌ Methylene chloride is best avoided. Legal? Yes. Desirable? Not really.
How to check your brew:
Some brands shout about their decaf method. Many don’t. If your label is silent, that’s a clue.
⬆️ Scroll up to check our list of brands by method, and consider switching if yours uses methylene chloride.
Choosing the right kind of decaf isn’t just about sleep or stress - it’s a modest change that may help prevent the kind of fall that changes everything.
You’re not just avoiding caffeine; you’re sidestepping hidden solvents, preserving polyphenols, and protecting future you.
That’s not giving something up - it’s protecting what matters.
🎧 If you’d rather listen while sipping your brew…
🎙️ This week’s episode of One Health Tweak a Week podcast brews the truth about decaf:
Which decaffeination methods are safest, and which may leave behind toxic residues
Why going decaf helped reduce falls in nursing homes by over 30%
And whether you’re sacrificing antioxidants in the process (spoiler: black tea lovers, you’re in luck)
👉 Listen now - while sipping your morning cup
(Psst: these episodes are free for now, but won’t be forever. If you’ve been finding value here, consider upgrading to stay in the loop and ahead of the curve.)
👉 What’s next?
💬 Do you drink decaf, or avoid it? Has this week’s tweak changed how you think about it?
📢 Know someone who still thinks decaf is pointless? Forward this to them - especially if they’ve had a fall, struggle with sleep, or just love a good brew.
❓ Spotted a label claim or health trend that doesn’t quite add up? Send it my way - I might tackle it in a future issue.
🔒 Want more smart, scannable science every Saturday? Upgrade to a paid subscription for bonus content, Q&As, and the warm glow of supporting evidence-based health writing.
Until next Saturday - stay curious, stay well, and stay kind to your future self.
– Ben
Excellent post and summary Ben. Thank you.
A smart read - I’ve investigated a few companies to identify a few that use paper or a sugar cane derivative in lieu of plastic - these are questions we should be asking and pressuring industry