Sometimes, we just need that beautifully smooth coffee flavour – without the caffeine jolt, but it brings about the question – is decaf coffee actually healthy?
- How do Decaf and Regular Coffee Compare?
- Is Decaf Coffee Good for Your Heart?
- Does Decaf Coffee Raise Blood Pressure?
- Is Decaf Coffee Bad for your Kidneys?
- So, in 2022 is Decaffeinated Coffee Healthy?
How do Decaf and Regular Coffee Compare?
Firstly, let’s make sure that we understand the differences between decaffeinated and regular coffee. After all, if we don’t know what is actually different, how can we really understand what we’re talking about.
Want to know more about coffee in general? Check out our guide to the basics of great coffee in 2022.
What is Decaffeination?
Decaffeination is removing some of the caffeine from any caffeine-containing product – it’s not just coffee that can be decaf, other examples include tea, chocolate, guarana, and kola nuts. You might think that decaf means no caffeine at all, however, the decaffeination process actually only reduces the caffeine content of the original bean, leaf, or nut rather than removing it completely.
In 2004 both Nature and the New Scientist magazine published articles about the discovery of naturally occurring caffeine-free Arabica coffee plants in Ethiopia. There is hope to breed a commercial coffee plant that is caffeine free and tastes great! Especially as the Coffea arabica plant is responsible for 75% of the coffee sold in the world.
However, so far no great news, in fact, in 2017 the Decadent Decaf Coffee Company dug into what had happened and found that like a lot of scientific discoveries the route was not straightforward forward and the funding was eventually lost.
Coffee sold as decaf is allowed to have a certain amount of caffeine remaining in it by law. The level depends on where you live – or rather which country you buy your coffee from.
In the UK decaf coffee has to have had at least 97% of the caffeine removed according to the British Coffee Association, which is the same as in the US. However, the EU is much stricter – requiring 99.9% of all caffeine to have been removed.
Types of Decaffeination
There are multiple different ways of decaffeinating the coffee beans so that you can get your coffee without the caffeine jolt. All of these are done to the green coffee beans before they are roasted. The decaffeination method has to remove the right amount of caffeine while not removing too much of the coffee flavour that we know, love and seek (sometimes blindly first thing in the morning!).
Swiss Water Process
The Swiss Water Process doesn’t use chemicals and can extract 99.9% of the caffeine under carefully controlled conditions. It was invented in Switerzland in the 1930s but entered commercial use in the 1980s
A green coffee extract is created by soaking green coffee beans in really hot water until all the flavours, aromas and caffeine have been removed from the green coffee beans and ended up in the water.
The green coffee extract is filtered using a carbon filter so that the large (relatively, we’re talking large on the scale of chemistry here, not so big you can see them with your naked eye!) caffeine molecules are trapped by the filter, but the yummy aromas and flavours stay in the green coffee extract liquid.
You now have boring, flavourless green coffee beans – which get thrown away (or hopefully composed, or recycled into something new), and green coffee extract liquid without the caffeine.
A new batch of green coffee beans is cleaned and soaked in water to get the optimum level of bean hydration.
Now things get interesting… and you get to remember your science classes! This new batch of optimally hydrated coffee beans has green coffee extract liquid circulating around it for between 8 and 10 hours. During this time the caffeine is drawn out of the coffee bean through osmosis (moving from an area of higher concentration to lower concentration) but the flavours and aromas remain within the green coffee bean because they are also at similar levels in the green coffee extract. The green coffee extract is filtered again and again to remove the large caffeine particles until the right level of caffeine is reached.
The beans are then removed from the process, dried and bagged for their trip to the bean roasting process – with 0.1% of their original caffeine and all of their flavour.
A side note – the caffeine removed from the coffee using the Swiss Water method can’t be recovered, so it’s actually burned from the filters (which are charcoal) as part of the regeneration process of the filter.
Carbon Dioxide Method
The Carbon Dioxide method, not at all surprisingly uses carbon dioxide to remove the caffeine from the green coffee bean. Now before you immediately think that this must be bad for us because carbon dioxide is EVIL and killing the planet, it is important to remember that it is also essential for plants to grow (it’s used in photosynthesis – its back to bio class again now).
It has been used to extract caffeine in industrial processes since the 1970s.
Carbon dioxide has a property where it likes binding to caffeine and can also when it’s pressurised at the right temperature becomes a supercritical fluid (sorry – back to the chemistry for a moment), behalfs like a mixture between a gas and a liquid.
- Green coffee beans are soaked in water (or ethanol) until they have 50% moisture content.
- The green coffee beans are then sealed into a pressure vessel, and pressurized to 300 atmospheres!
- Supercritical carbon dioxide is pumped into the pressureized vessel where the caffeine moves from the coffee beans into the carbon dioxide. The caffeine laden carbon dioxide is pumped thorugh extractors and scrubbers (to remove the caffeine) before being recirculated back through vessel with the coffee beans to pick up more caffeine. This cycle goes on for up to 12 hours!
- Once the 12 hours have passed, the green coffee beans are removed to another vessel and the pressure is gradually released. When this happens any remaining carbon dioxide returns to its gas form and evapourates leaving only the caffeine behind which can be filtered out so that the carbon dioxide can be reused.
- The green coffee beans are then bagged up for their trip to the roasting process.
The caffeine extracted using the carbon dioxide method is recovered and goes into soft drinks, cosmetic products and the pharmaceutical industry.
There are two different methods that fall into the solvent method of decaffeinating coffee. The same chemicals that bind to caffeine are used in each. These are Methylene Chloride and Ethyl Acetate.
The Direct Solvent Method:
- Green coffee beans are steamed to open up their pores and bring the caffeine molecules to the surface (much like steaming your face as part of a facial). This takes approximately 30 minutes.
- A chemical solvent that bonds to caffiene is added and the green coffee beans are washed in it for around 10 hours.
- The green coffee beans are washed to remove the solvent and then steamed.
- The green coffee beans are dried and sent off to be roasted, removing the remains of the solvent residue (in theory).
The Indirect Solvent Method:
- The green coffee beans are soaked in hot water for a number of hours to remove the caffeine molecules (and, as you’ll recall from the first step of the Swiss Water Method – a lot of the flavours come out too).
- The green coffee beans and the water are seperated, and the water is treated with the solvent that binds to the caffeine.
- The water and solvent mixture is heated so that the caffeine molecules and solvent evapourate, and then the beans are placed back into the water and flavour mixture to reabsorb the flavours.
- Once as much of the flavour has been reabsobed as possible the green coffee beans are dried and sent off to be roasted, removing the remains of the solvent residue (in theory).
Is Decaf Coffee Good for Your Heart?
In 2005 WebMD reported on a study suggesting that decaf coffee might actually have harmful effects to your heart.
So in 2022, we thought we’d revisit the question, is decaf coffee good for your heart and see if the advice has changed!
There are 3 major American studies that tend to be discussed when talking about heart health and coffee. The Framingham Heart Study, the Atherosclerosis Risk in Communities Study and the Cardiovascular health study are all based on US trial participants. In analysing all of them, Dr David Kao has found that contrary to popular belief, the caffeine in coffee may reduce your risk of heart failure – but decaf doesn’t have the same effects.
However, to balance this – there was a 2019 study (of white, British participants only) led by Professor Elina Hyppönen that has found that people with a genetic vulnerability to heart disease were actually more likely to unconsciously choose decaffeinated coffee. This suggests that it is possible that an underlying heart health issue that causes the person to choose a decaf coffee – not the decaf coffee causing the underlying heart health issue. So we’re at a chicken and egg scenario here.
Although Dr Kao has also found that in the case of overweight decaf coffee drinkers (BMI above 25), drinking 3-6 cups of decaf coffee (black though – so throw away your milk, cream, sugar and sweeteners), increased their “good” cholesterol by up to 50%.
But before we leap completely onto coffee and cholesterol – it is important to consider what component of coffee, in general, could affect cholesterol. It might surprise you to know that your method of brewing your coffee might be contributing!
Consider this – there are multiple studies suggesting that the naturally occurring oils in the coffee bean are what actually affect the cholesterol level – and the amount of these in your coffee can be affected by how you brew it.
Paper filters and small portions
The major benefit of using paper filters is that the oils in the coffee bean are retained in the filter, giving you the most flavour without increasing your cholesterol. The alternative is drinking something like espresso, where the small portion size reduces the amount of cholesterol increasing oils in your coffee serving.
Instant coffee (high octane or decaf) actually contains very little of the naturally occurring oils anyway, so if you’re concerned about the cholesterol increasing effects of coffee oils – it’s also a good bet.
Any form of boiled, or mesh filtered coffee increases the coffee oils that make it through to the drink, so these are the ones to avoid if you’re concerned about cholesterol.
Another element to consider is what you’re adding – ie milk, creamer or sugars. High-fat milk and cream will naturally also increase cholesterol, so your best option is to drink your coffee black. And before you tell me it’s disgusting and you can’t – perhaps you need to try a different way of making your coffee!
So while there is no real conclusion on whether decaf coffee is better or worse for your heart than caffeinated coffee, there are 3 recent studies showing that caffeinated coffee (also drunk black with no sweeteners) in moderation has links to reduced risk of heart failure – but they go on to say that’s the caffeine… any caffeine!
Does Decaf Coffee Raise Blood Pressure?
Now according to John Hopkins Medicine, not everyone’s blood pressure is sensitive to caffeine, but if yours is, then reducing your consumption of caffeine can help reduce your blood pressure. So what does this mean for decaf coffee?
Well, it turns out, caffeine might not be the only substance in coffee that causes changes in blood pressure – at least so says Dr Roberto Corti, a cardiologist at the University Hospital in Zurich in a 2002 study. He found that people who only drank coffee occasionally had increased blood pressure after a triple espresso. Not surprising at all you say… and I agree – except that the surprising part is that the same reaction happened whether it was a decaf triple espresso or a standard one… if a triple espresso can ever be considered standard!
However, if you’re already a coffee drinker – the results are a bit different. In a 1989 study reported in the Journal Hypertension, regular coffee drinkers who switched to decaffeinated coffee were found to have an overall blood pressure reduction over the course of the study.
Is Decaf Coffee Bad for your Kidneys?
The Association of UK Dietitians advises that coffee is high in potassium – and adding milk (which most of us do) increases this already high potassium level – bad news for those with kidney disease. But what does this mean for your kidneys if you fancy drinking decaf coffee?
Well, there is some good news – and some bad news. Coffee itself is considered a low potassium food according to the US National Kidney Foundation. However, that’s one cup of coffee… it stops being low potassium when you’re looking at drinking 3 or more cups of the black stuff – or less than that if you’re adding milk.
Another strike against decaf coffee is a September 2012 article published in Nephrology Dialysis Transplantation where a study by lead author Miguel Bigotte Vieira found that a greater life expectancy of patients with chronic kidney disease was related to an increase in caffeine intake.
Now, you may have heard about coffee and the risk of kidney stones. There are 3 large studies that have started to cast some doubt on this by showing links between caffeine-rich beverages (particularly coffee) that may actually protect against kidney stones. So does that mean decaf is out?
No, as it turns out! In a large scale 2013 study, there was a reduction in the risk of kidney stone formation associated with drinking decaf coffee by 16% – this is not as impressive as caffeinated coffee at 26% reduction, but better than tea at 11% reduction.
So, in 2022 is Decaffeinated Coffee Healthy?
As always, it’s something that will be personal to you and any underlying health conditions should be discussed with your doctor or registered nutritionist. In general, decaf coffee seem to be on par with caffeinated coffee in terms of health – with minimal differences associated with the removal of the caffeine.
The health effects of coffee will depend on how your body reacts to coffee, how you make it, what you put in it and finally some small effect of the decaffeination process.
Overall Decaf Coffee Benefits
Decaf coffee contains the majority of the antioxidants present in regular coffee, so with the exception of caffeine, you’re already getting most of the benefits. If you’re trying to avoid the caffeine-related jitters, insomnia or anxiety while still enjoying the smooth taste of coffee, give it a shot.
Other benefits include:
- A large study shows decaf coffee reduces the risk of kidney stones
- Regular coffee drinkers switching to decaf have experienced blood pressure reductions
- There is some evidence for cholesterol reducing effects – but it may be related to genetic predispositions or your method of brewing coffee – or even the milk, cream or sugar you add to it!
- Decaf coffee is often recommended during pregnancy
Decaf Coffee Downsides
It is worth noting that if you already know you’re sensitive to coffee – it might not be the caffeine that is the cause of your sensitivity. So while it may be worth you trying decaf coffee to see how you react – don’t be surprised if you have a similar reaction to caffeinated coffee.
Depending on the decaffeination process, there is some potential that trace amounts of the chemicals used in solvent-based decaffeination may still be present in your coffee.
So what do you think, will you be switching to decaf in 2022? Let us know in the comments.