ZOE Science & Nutrition - Recap: How to pick the right bread for your health | Prof. Tim Spector and Vanessa Kimbell

Episode Date: September 3, 2024

Bread has been a staple of our diet for literally thousands of years. Around the world, millions of us start the day with a slice of toast, enjoy a sandwich for lunch, or tuck into a burger bun for dinner.  But all bread is not baked equal. Professor Tim Spector and Vanessa Kimbell are here to help you choose the right type for your health. 🥑 Make smarter food choices. Become a member at zoe.com for 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: 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 MenoScale Calculator - learn about your symptoms 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 Zoe Recap, where each week we find the best bits from one of our podcast episodes to help you improve your health. Today we're discussing bread. Bread has been a staple of our diet for literally thousands of years. Around the world, millions of us start the day with a slice of toast, enjoy a sandwich for lunch, or tuck into a burger bun for dinner. But all bread is not baked equal. Professor Tim Spector and Vanessa Kimball are here to help you choose the right type for your health.

We are assuming that the bread that we're buying is nourishing we have to stop and look at it and look at the label so that's your first thing never pick up a bread without looking at the label and turning it over the second you see an extremely long list of things you cannot pronounce or you do not recognize put it down it doesn't matter what the label says on the front, put it back. Be prepared to put that bread back on the shelf and say, no, I am not accepting this bread today. I want something that is going to nourish me. I'm not feeding myself, I'm nourishing myself. So that is about changing your attitude. Then you need to look out for the simplest of ingredients. Let's start with flour water salt

but the thing that i get really excited about is actually the level of fiber and the proportion of fiber on the label so i tend to if i have to buy bread in the supermarket i tend to look for anything above six grams per hundred grams minimum what would be the sort of spreads that you'd be advising listeners to try if they're starting out on this journey? I'd be looking for the words whole grain. But even then, there are problems that, as Tim mentioned, that some people can fake it. It looks like it could be good. That's why I'm saying you need to get in a relationship with your bread and dig a little deeper, find out a little bit more about it, because they can fake that whole grain-ness. And a few extra tips and tricks here. So words like granary mean nothing and malted loaf is actually just adding probably more sugar to it. And so there's lots of ways that you're being

fooled when you buy bread. If there is a label, try to look at the carbohydrate to fiber ratio and that should be relatively low. So it should be around four or five to one for a decent loaf. The worst kind of supermarket bread is about 17, 20 to one ratio. So there's a huge difference in that. Now, beware, though, that in many supermarkets, that smell of bread hits you as you go around the aisle. And those breads they make on the premises don't have a label and they just put them in bags. And you've got no real idea what's in them. It's all a big con because that bread is often a year old. Oh, really? I was gonna say, it sounds good. They made the bread in the premises. Surely,

this is the best stuff, no? No, it's pre-frozen. It's pre-cooked. And basically, they just have to defrost it and give it a final toasting. That's how they get away with making it this so-called fresh, you know, baked on the premises. And it means they also don't have to put a label on it. I don't have to say what additives they put in it. It's all a giant con. But it does smell nice and makes you extra hungry as you're going around the supermarket. What about the gluten? You mentioned it right at the beginning. I think there's a lot of people who are concerned about being sensitive to gluten. Bread is the number one thing that people associate with this. How should people think about this?

Well, 1% of people, one in 100, actually have a real sensitivity or an allergy to gluten. And these people have celiac disease, and it's a relatively common, if you think one in a hundred is common, autoimmune condition that this doesn't apply to. They will be vomiting, they'll feel really sick, won't be able to gain weight. There's no in-between area there. But recently, in the last 20 years, we've seen this massive increase in gluten sensitivity, which is people that don't have the antibodies, they're not physically sick, they just might feel bloating or other symptoms when they feel that they're eating gluten. And this percentage is going up all the time. And it's latest surveys around 10% of people

say they have gluten sensitivity. When these people are actually tested blind with, say, gluten-free pasta or gluten pasta, and they're not told which is which, about 80% of them turn out not to be gluten sensitive. They have just got it wrong, or they've just made a mistake because the gluten is associated with other foods. So there's a whole group of people that are mistaken that it's gluten that's causing their problem. There are still some people that do have a sensitivity to it, and they may well have other conditions like irritable bowel syndrome or other allergies, which have increased dramatically in the last few years, but may just be a general symptom of their problem rather than

the cause of the problem. And that's, I think, where most of the scientists and doctors in this field are coming from, that no one really believes that gluten is causing these problems other than for the celiac. It is just a sign that people eating gluten-type foods or maybe cheap sandwiches or other things that contain it, they're eating other things along it that are giving them bad microbes. The worse your state of your microbes, the less you're able to, in a way, deal with some of the foods we eat. And this is a bit of a symptom of the Western gut. But as I said, most people are actually mistaken and they're not intolerant of gluten when they're tested in a scientific way. I think that's very important to realize.

If we've cleared that up, Vanessa, can you clear up the sourdough mystery for us? So it's almost impossible now for me not to buy some bread that says sourdough on it. I'm still a bit unclear though, really what it is. Could you help us to understand and maybe Tim can help us understand if you know there's really the health benefits associated with this as well. So I'm currently finishing my doctorate in nutrition and digestibility of bread. Most of my work for the past 20 years has been combining the potential health benefits of sourdough and long slow fermentation with that understanding of how that plays with the gut and the microbes in the gut and the impact on mental health. So the first thing to say is sourdough is a combination of

wild yeast, that's yeast that's in the air and yeast that you capture, and lactic acid bacteria. Now, you'll be familiar with these bacteria because you will have come across them in yogurt. You'll come across them in vinegar. Even coffee and tea is fermented. Cheese is fermented. So we're very, very, very familiar with these microbes. And we know that what they actually do is they feast on the available sugars. And there's a symbiotic relationship with the yeast. And they produce two types of acid. Now,

the first type of acid is lactic acid. That is kind of a yogurty flavor. And the other acid is acetic acid. And that's more what you would recognize as being vinegar. And when you combine these different acids what actually happens is the acidity triggers this incredible change that goes on and transforms the dough that's not the acidity that actually on its own transforms the dough it's part of the equation because of course when you put acid on anything it's going to break it down which is one part of it but the other part of it is very interesting and that is they trigger this amazing thing that's already in the grain

and that is enzymes now if you think of enzymes as being like edward scissorhands they chop everything up and this ability to chop everything up is actually one of the key things that changes the way that the flour is structured and the way that the dough behaves. So one of the things that allows people to eat sourdough is that long, slow fermentation and those enzymes neutralize the phytic acid, making it easier to digest, but also unlocking the minerals, making it more nutritious. That's a win-win. how long does this process take you're describing this long slow fermentation with like wild yeast how does that happen and can that only happen if i'm sort of doing this at home or in some sort of artisanal bakery in which case is this relevant for like large-scale feeding of people so it's not just the length of fermentation, you are correct. You can ferment a sourdough in a very short space of time, you can make them in six or eight hours, or you can leave them longer. But because of this chain reaction, we tend to

think of the longer you ferment it, the more broken down it becomes. So if you have digestive issues, then fermenting it overnight, which is called a retarded method, will generally break the flour down more, making it more nutritious, easier to digest, and is an all-round healthier bread than, say, something that was short-fermented. Just to clarify, you might have got the impression it's really complicated, Jonathan, but actually... It sounded really, really complicated to me, yes. But actually, Vanessa has actually written a book about how to do this really, really quickly, you know, the 10-minute approach, that if you've got everything ready, it just takes you a few minutes to put everything together because the microbes do the work.

Give me the 10 minute one. I think you scared me a bit, to be honest. I was getting a bit excited and now I'm retreating. Give me the like... Well, I do this. Go on. Well, I now do this, following Vanessa's coaching. And you keep a mother in the fridge.

And from the old, you just keep recycling a bit of the old dough with the microbes in it. It's resting in the fridge. You mix it with some flour and some water. And then that takes you five minutes. And then you come back the next day and then you add it more flour and more water to make up half a kilo. And then you leave it to rise. Then you put it in the oven then you eat it and really that's

it the work is done for you by the microbes and this is why if you've got a regular schedule now people are working out it is dead easy to do this and you can just mix in anything you really want to into that flour and this is what everyone used to do before 1963 when we all got converted into plastic bread. So that's really important to realize. And I think it has, as you said, health benefits. And there are studies showing that people with celiac disease who would normally be vomiting with bread, many of them, not all, but some of them, when they have sourdough

bread, actually were able to tolerate it, which is really interesting because it means that the protein in the sourdough bread is very different to normal breads. And the bit that's triggering these reactions is very much less. So gluten is still there, but the way it's presented is different. Your own research actually showed that sending out mothers to all parts of the world, so everyone leaves a bit of water and flour on the side of their sink, and then the natural yeast and bacteria flood in. And it turns out when you do that, they're all very different and it makes your bread actually all very different. So all the starters around the world are all slightly different, which is a nice story about how all our guts are different. And so it's this

amazing uniqueness of all these methods that are really important. But I'd love, Vanessa, to talk about fake sourdough and how supermarkets are selling to people like Jonathan as sourdough when actually there's nothing live or real about it other than perhaps the smell. Now, there are commercial producers of sourdough in large quantities that are making real sourdough. You have to look for the words that tell you that it is real sourdough and long-slay fermented using live culture. At this point, we are completely reliant on the manufacturers communicating those facts to us. Just the word sourdough doesn't cut it. So don't believe it. If it says sourdough pizza, can I now just eat as much of that as I want and I'm healthy?

Because if it's real sourdough, it's all going to be fine? Or is that... The thing is, Jonathan, sourdough itself is a process. Look at what you're actually processing. If you're still processing refined white carbs, no. So coming back to your lovely pizza, Jonathan, no, no. Sourdough on its own with white, if you don't have the fiber in there, it's pretty pointless. You might at best increase resistant starch, which might slow down a bit of your blood sugar response. And the fat from your lovely cheese might do that. But no, no, no, no, no. We need to look at the combination of whole grain, live bacteria and time. And then you can have your lovely pizza

with a glass of wine and enjoy it. If we do want to eat bread, are there any other top tips about how to make sure that we can do that in the healthiest way? Maybe starting with Tim? Well, it's just to reiterate that bread is still a good source of fiber and proteins, but if you get the wrong ones, it's going to cause you really bad sugar spikes. Always choose rye and whole grains and breads with mixed flours and added seeds when you can. And remember to look at a label when there is a label to try and get as low a carbohydrate

to fiber ratio as possible. And a really simple ingredient list. Go to a specialist baker, artisan baker, be prepared to pay more money for it. It is worth paying that extra money for the slow fermented sourdough bread that we've heard so much about. That's all for this week's recap episode. If you want to learn 10 science-backed tips to improve your health for some of this podcast's most popular episodes, you're in luck. You can download it from zoe.com slash free guide. Or if you're looking for another episode to listen to today, why not try a popular episode of Zoe Science and Nutrition like what to eat to avoid osteoporosis,

how to prevent heart disease, or mushrooms as medicine. Search for them on your favorite podcast player.