Tannins are a set of fascinating plant-based compounds. They’re most famously found in tea and red wine, but there are tannins in plenty of other foods and drinks too. So, does coffee have tannins? It’s an important question, given that we drink coffee so often.
The simple answer is yes. The tannins are why coffee dries your mouth out in the way that it does. However, there’s some complexity to the topic. For one thing, the definition of a tannin isn’t clear cut. You’ll sometimes see particular compounds get classified as a tannin by one author and not by another
Thankfully, there’s a ton of information out there about tannins, including how they function, what they mean for health, and where you find them. We’re going to cover all of those topics today. And, as we’re focusing on coffee, let’s also take a quick look at what coffee means for your health.
Coffee And Tannins
What Are Tannins?
To truly answer the question about coffee and tannins, we need to look closely at tannins. The broadest definition is that tannins bind to proteins.
This doesn’t sound like much of a definition, but that’s part of the problem. It’s very difficult to get more precise with tannins, as there are many mechanisms for protein binding. The variety of mechanisms means that tannins can vary dramatically in their structure.
This definition makes it difficult to classify tannins and to test for them.
Part of the problem is that tannins just need to bind to a protein to fit the classification. No test will ever contain every type of protein, so you can easily get a positive outcome from one test and a negative one from another. Frustrating, right?
Tannins In Coffee
Coffee is generally said to contain tannins. The astringent effect makes this seem obvious. Studies also reinforce the idea, suggesting that tannins and caffeine are the most valuable compounds in coffee. You may also hear it said that coffee contains around half the tannins as you get in tea.
But, as we mentioned before, testing is complicated. Some tests suggest that coffee has tannins, while others show the opposite. This is partly because the chlorogenic acid in coffee only tests as a tannin some of the time.
There are also claims that coffee contains pseudotannins, rather than true tannins. That adds a whole new layer of complication, as pseudotannins are actually sometimes seen as a type of tannin anyway.
The best answer is that, honestly, we don’t know.
The astringency and bitterness of coffee make it easy to assume that there are tannins. Perhaps there are. Or, perhaps other compounds in coffee create this flavor profile.
While we can’t be certain whether or not coffee contains tannins, it’s still worth digging into the benefits and risks of tannins. This way you know what to expect. These features are relevant to any other tannin containing food or drink anyway, including red wine and tea.
Does Roasting Affect Tannin Levels?
There’s scarce research into the relationship between tannin levels and coffee roast (that’s not too surprising, given that we’re still trying to work out whether coffee even has true tannins).
Some theories suggest that the tannin level increases with roasting. If so, light and medium roast coffee is your best bet for keeping tannin intake low.
Other theories suggest that tannin levels first increase, then decrease. This would make dark roast lower in tannins.
With such contradictions, it’s impossible to say anything definitively. Besides, the type of coffee, growing conditions, and brewing method might actually impact the tannin level more than the roasting of your coffee beans.
The best approach is to pay attention to how your mouth feels. Does the coffee have a strong drying effect? If so, the tannin content is likely to be high. The tannin content should be lower if the coffee isn’t very bitter and doesn’t dry your mouth out much.
Fermented Coffee And Tannins
Interestingly, fermenting coffee does appear to lower tannin levels. This may include coffee beans that are fermented (perhaps intentionally or perhaps because they were first digested by an animal) or coffee that has been brewed and then fermented.
Either way, you’re generally getting a lower tannin drink with a different flavor. Fermented coffee won’t appeal to everyone, but it’s worth trying at least once.
Some Benefits Of Tannins
So then, let’s look at what tannins actually do for us. There are some clear benefits, along with a few risks.
To keep us healthy, our bodies often balance opposing mechanisms – like free radicals and antioxidants. Free radicals cause chains of reactions throughout our bodies. That effect is known as oxidation and is important for our immune system.
Antioxidants help to stabilize free radicals, reducing their reactivity and preventing some of those reaction chains.
For us to function well, our bodies need a good balance of antioxidants and free radicals. Unfortunately, modern diets and lifestyles often promote free radical production, leading to high amounts of oxidative stress and an increased risk of harm.
Too much oxidation for too long can easily increase the risk of disease and cause considerable harm.
Tannins are antioxidants, which makes them an excellent tool for fighting oxidation. Other compounds in coffee have antioxidant effects too. In fact, coffee is a shockingly powerful source of antioxidants.
Can Help With Inflammation
Like oxidation, inflammation is an essential process, one that can easily get out of balance. Tannins help to make things better by decreasing inflammation levels.
In the process, they may lower the risk of a range of inflammation-related diseases, including asthma, heart disease, and rheumatoid arthritis.
Coffee is interesting here, as it’s often thought to increase inflammation. Yet, research suggests the opposite, showing that drinking coffee regularly decreases inflammation and helps to protect you.
They’re Important For Your Heart
Plant-based compounds are often valuable for heart health, helping lower cholesterol levels and blood pressure, while also decreasing heart disease risk.
Tannins are no exception. In fact, high tannin red wines may even be better for your heart than low tannin wines. Tannins could even be more relevant than the resveratrol that red wine is famous for.
Remember too that most tannin rich foods and drinks help with your heart. Is that a coincidence? I don’t think so.
Could Protect Against Neurodegenerative Disorders And Cancer
Neurodegenerative disorders, like Alzheimer’s disease and Parkinson’s can be terrifying. Not only are the disorders devastating, but there’s also so much we don’t know about them and they have no known cure. While the treatments we do have show promise, they also leave much to be desired.
Cancer is similar, especially as it can come out of nowhere and affects people even at the peak of their health.
Your diet is never going to completely protect you against such conditions. However, eating well could lower your risk. Tannins are an excellent choice here, as they have been linked to decreased risk of cancer and neurodegenerative disorders.
The anti-inflammatory and antioxidant effects of tannins are highly relevant here. However, other features of tannins may be protective too.
May Help With Your Mood
While the evidence is scarce, some theories suggest that tannins can improve your mood by increasing levels of serotonin and dopamine.
Coffee itself can also help to improve your mood – and not just because it boosts your energy. Indeed, caffeine is even thought to help with depression symptoms. Impressive, right?
The Problems With Tannins
While tannins tend to be good for you, there are a few risks to watch out for as well. These are particularly important if your tannin intake is high.
They Can Decrease Iron Absorption
The first is that tannins can lower your iron absorption. The effect can easily be significant, especially if you have multiple cups of coffee and tea per day or if your iron intake is low anyway.
The caffeine in coffee could make this issue even worse. This isn’t just theory either. Studies do show that coffee decreases iron absorption.
This effect could even seriously compromise your health if it leads to iron deficiency anemia. You can decrease your risk by drinking coffee between meals rather than during a meal. Watching out for iron deficiency symptoms can help as well.
May Lead To Headaches
A second problem is headaches.
While there isn’t much evidence here, plenty of people do seem to get headaches from consuming tannins. Coffee is even more problematic because the caffeine can have a similar effect. The combination of the two areas could easily increase your risk of headaches, especially if you’re sensitive anyway.
Thankfully, the headache effect isn’t universal. Many people consume tannins regularly without any issues at all.
Can Promote Teeth Staining
Tannins can also contribute to teeth staining by making it easier for stains to stick to your teeth. This effect varies depending on exactly what you’re drinking and its color intensity.
Unfortunately, black tea and dark coffee are the biggest culprits here.
You can decrease your risk by rinsing your mouth out after each cup of coffee. Adding a little milk can help too.
Is Coffee Healthy?
We also need to talk about coffee itself. After all, you’re not just drinking tannins. There are plenty of other compounds present too, which can all impact your health.
Coffee is fascinating in this regard.
It’s often seen as an unhealthy habit, where many of us feel like we probably should be decreasing our intake or cutting coffee out entirely. Yet, we rely on coffee for energy and for a mood boost.
Despite all these concerns, coffee isn’t that harmful. Research consistently shows that coffee can help with your energy and ability to concentrate. It can boost your mood, can reduce the risk of many diseases, and may even lengthen your life.
Tannins don’t have that many risks. The biggest problem is that they lower your iron absorption, but you can easily work around this by drinking coffee between meals. Most of us already do so.
Besides, it’s clear that coffee itself has benefits. Research consistently shows that. Drinking coffee could even help you to live longer, as long as you’re not loading it up with sugar and cream.
Finally, remember that coffee is just one potential source of tannins. You’re probably getting tannins elsewhere in your diet too, like from red wine.
If you’re worried about tannin intake, focusing on low tannin red wine may help matters. You could also just skip the red and go for white wine instead. Similarly, choosing green tea instead of black tea and shortening the steeping time will also help decrease your tannin intake.