ZOE Science & Nutrition - Recap: Is your morning coffee harming your health? | James Hoffmann

Episode Date: February 25, 2025

Today we’re diving into coffee. Most of us are greeted by its earthy aroma every single morning. It’s hot bitter taste signaling that the day has officially begun. Coffee is so ingrained into our daily routine we rarely pause to consider the effect of coffee on our health.  So, what is coffee, a health-boosting elixir or just another guilty pleasure? Coffee expert James Hoffmann joins us to explore one of the world's most popular drinks. 🥑 Make smarter food choices. Become a member a zoe.com - 10% off with code PODCAST 🌱 Try our new plant based wholefood supplement - Daily30+ *Naturally high in copper which contributes to normal energy yielding metabolism and the normal function of the immune system 📚 Books from our ZOE Scientists: The Food For Life Cookbook by Prof. Tim Spector Food For Life by Prof. Tim Spector Every Body Should Know This by Dr Federica Amati Free resources from ZOE: Live Healthier: Top 10 Tips From ZOE Science & Nutrition  Gut Guide - for a healthier microbiome in weeks Have feedback or a topic you'd like us to cover? Let us know here Listen to the full episode here

Hello and welcome to Zoë Recap, where each week we find the best bits from one of our podcast episodes to help you improve your health. Today we're diving into coffee. Most of us are greeted by its earthy aroma every single morning. It's hot, bitter taste signaling that the day has officially begun. Coffee is so ingrained into our daily routine, we rarely pause to consider the effect it has on our health. So what is coffee? A health boosting elixir or just another guilty pleasure? I'm joined by Professor Tim Spector and coffee expert James Hoffman to explore one of the world's most popular drinks. Well, for many years we thought coffee was bad for us because short term, it increases

your heart rate, increases your blood pressure. For decades, people said this is a rather dangerous thing to be having, don't do too much of it, you're going to have a heart attack. Then they started doing some proper studies and they've shown that you actually, based on over 25 studies, you can now see a reduction of about 25% in your risk of a heart attack or heart disease. So then you're saying, why would that be? Something that's short-term, slightly stressing your system is actually long-term good for

you. And I think it's seeing as coffee as this whole, coffee as this fermented plant that has microbes acting on it, has hundreds, thousands of chemicals produced from it, and it's probably a combination of all those things that gives it this health benefit, such as the fiber in it. And we used to think, not think of coffee as a fiber rich drink, but we now know that broadly you can get about 1.5 grams of fiber out of a cup, which means if you're having three cups a day, that's You know 4.5 to 5 grams of fiber which it's a quarter of your daily fiber intake in the UK and the US. I always find it extraordinary because I always somehow in my mind think about fiber as being like this roughage that you can't like brand exactly or like the stuff that my grandmother might stir into a glass of water.

Yeah, and two cups of coffee is more than a banana in terms of fiber. But the point is it's a drink, so like where's all that, I don't remember, you know, where's all the solid bits of fiber, and this is because of my understanding fiber isn't quite right, is that? Well that's right, well fiber can be in drinks and can be these small particles that are still gonna have a similar effect when they reach the lower part of your intestine where all the gut microbes are. And there are soluble fibers and there are insoluble fibers

and they may be, some of them might be be invisible so I think that's the way it dissolved into the drink it's not gonna be fiber and something you can't even see which we always think about like it's just like eating spinach yes but actually it's not like that and there are lots of different ways that we can get fiber into our body and until recently we didn't appreciate this and it's not in most nutrition textbooks as health drink, but there's more fiber generally in coffee than an equivalent amount of orange juice, for example.

So it's not sufficient. I'm not saying you can live just on coffee and have a good diet, but given that in the West we're very fiber deprived, it's actually perhaps the thing that's just keeping us going on this very low fiber diet and making up perhaps a quarter of a third of our fiber amounts. So it's the fiber, but it's also these individual chemicals that we're still just getting to understand and this range of polyphenols that are in the coffee beans some of them are

so enhanced by the microbes as they ferment it and those are released and those have direct effects on our on our body and some can reduce blood sugar and reduce stress and body and some can reduce blood sugar and reduce stress and actually reduce blood pressure and things like this. So it's a complex area, but I think we're suddenly putting it together from a drink that was demonized as being very harmful to us to something that actually could be beneficial. And the other interesting thing is we always thought it was about the caffeine and The studies have now clearly shown that you get nearly as much benefit on the heart with decaffeinated coffee and Again, it comes back to this idea of how we see foods as we was thinking there's one thing coffee is all about caffeine and you know

Lemons is about vitamin C and we forget everything else. But Clare's all these other stuff going on in that food that can give us these huge benefits. I think it's the great frustration of coffee conversation is the substitution of coffee and caffeine. It's this incredibly well-studied drug. We know a lot about caffeine, but it's not all that coffee is, but it ends up being all that we talk about

most of the time when people wanna talk about coffee and health. Do we understand that coffee is, but it ends up being all that we talk about most of the time when people want to talk about coffee and health. Do we understand why coffee is full of not only caffeine, but all of these other polyphenols? What's it, most of us think about coffee as being either something ground that we buy from our grocery store, or maybe we think about it as like this like blackened thing that looks a bit like a bean,

but we definitely don't think about it as a plant or anything else. What's the? The caffeine is easier to sort of understand the presence of. It's primarily produced by the coffee in the coffee fruit. So coffee beans grow in sort of a cherry. It's about the size of a small grape with two peanuts like seeds in the middle. So if you look at a coffee bean, it's too flat size. They would typically face each other. Um, as a defense mechanism, the plant produces caffeine to act kind of as an

insect repellent, for want of a better term, uh, to discourage insect attacks on the fruit. That's, that's really why it's there in the quantities that it is. Therefore you tend to see species of coffee that are hardier and more robust, one of which is Robusta, grows lower, more insects are present, twice the caffeine levels of something like Caffeia arabica, which grows higher up and obviously has less challenge, and so it needs less defense. But yeah, that's the primary reason caffeine exists. Caffeine is produced by other plants.

Yeah, tea leaves as well. So I mean, green things, I mean, not green, more black tea ones for the same reasons. And polyphenols themselves are also what I understand defense chemicals is how I've heard you and others describe them, Tim. Yeah, this is, again, it's an incredibly broad family, but in general, these are chemicals produced by plants to defend themselves not only against insects but it might also be against high winds or it could be cold or it could be strong sunshine or it could be to change the way predators, the taste and things that for predators.

But generally, it's a defense mechanism for plants that ends up having a side effect of being beneficial for our gut microbes. That's how nature is, as, as cameras full circle. Imagine that I'm going into a coffee shop rather than making this at home. What is James's top tip for picking the best coffee in that situation? First and foremost, I'm going to be pro independent coffee shops. They have a different motivation. They're trying to win you over with the quality of the product, not with

convenience and familiarity, which is how chains tend to work. So it's worth the gamble to find a good independent coffee shop. They'll care more about the coffee. It'll be fresher. It'll probably be of higher quality. It'll probably be theoretically higher in things like polyphenols, which that is a broad statement and I'm very nervous making it, but you would hope that would be the case. And so that would be the first thing.

And then I think, you know, as long as coffee is well brewed, which again, independents these days tend to do well, whether it is a flat white or it is a filter coffee or it is a straight espresso, it's actually a matching kind of extraction of the raw material across all of those things. And so you should see the benefits kind of regardless of your preferred drink. But you know, people or independent businesses are excited to talk to you about what you like and help you find something that you like. And it's always worth a conversation and finding your local sort of place.

I think we don't have that feeling as much anymore of like your local coffee shop. And that's a shame, you know, that's the thing that dependents offer over chains too is community, space, experience. So yeah, all of those things is why I'm pro independent business. And one question that we were asked a lot from our listeners

was what about people with high blood pressure? So Tim, you've been talking about all the great health benefits of coffee, but you also mentioned, I think that historically people were told not to drink coffee because it raised blood pressure. If you have high blood pressure, what's your advice? I think if your blood pressure is not under good control, then you have to be very careful with coffee and caffeine. But all the studies suggest that if you're just starting to drink coffee, it's only the

first few weeks that your blood pressure will go up and then it stabilizes. So I wouldn't advise anyone to completely change their diet or anything they're doing if they don't have stable blood pressure. Get it stable and then start to slowly introduce coffee into your diet. It's not as far as I'm aware a contraindication if your blood pressure is well controlled. I monitor my blood pressure and coffee has no effect on that. And there's some evidence that long term, it might actually reduce your blood pressure. Got it.

So you're saying if someone's listening to this and they have high blood pressure, but it's under high control and they like coffee, you're not saying you need to give up. No, there were old studies, they're out of date. They showed that people who hadn't been exposed to coffee, if you give them large doses short term, your blood pressure can go up. So obviously if you have a problem short term, you don't want to have that problem, but if it's well controlled, then no real problem long term. And long term we know from all the epidemiology that for the average person, they will get

derived benefit in terms of their heart health. But the caveat, as always, is everyone is an individual and all our responses are going to be different. We can't give advice that is going to apply to absolutely everybody. We're talking at this point averages. And there's always decaf. Yes. everybody, we're talking at this point averages. And there's always decaf. Yes, so there's always decaf.

And I think the blood pressure story was mainly about the caffeine side of it. So as we've heard, decaffeinated coffee is safe. The chemical processes are now considered very sophisticated and safe. There's plenty on the market. Find one that you like, no need to have caffeine.

I think everyone's got to work out, you know, there are lots of factors that affect your caffeine metabolism, work out what suits you, experiment, find out, you know, but for many people it does get them going in the day and gives them a clarity of thought, you know, in their thought processes and other things that are important. And that's why I have coffee in the morning, but I don't have it at night. Thank you for listening to today's recap episode. I want to take 30 seconds to talk about something that's not talked about enough. Menopause. Over half the people on the planet experience perimenopause and menopause. Yet symptoms are often misunderstood or dismissed.

At ZOE, we're moving menopause research forward. We recently conducted the largest study of menopause and nutrition in the world. And our study showed that two-thirds of perimenopausal women reported experiencing over 12 symptoms. Symptoms like weight gain, memory problems and fatigue. The good news is the results also show that changing our food habits may reduce the chance of having a particular menopause symptom by up to 37% for some women. We know how important it is for you to be able to take control of your own health journey. So we've created the Menoscale Calculator

to help you score the frequency and impact of your menopause symptoms. Go to zoe.com slash menoscale to get your score. The calculator is free and only takes a couple of minutes. And by the way, we've spoken about perimenopause and menopause many times since starting the Zoey Science and Nutrition podcast. To find these episodes, simply search Zoe Menopause in your favourite podcast player.