Dr Rupy: Carbohydrates are a food component that is regularly debated in the nutrition world, and they have a bad reputation for weight loss and diabetes, but on the other hand, they are prioritised by athletes. And there's been quite a few studies on the associations between total carbohydrate intake and health outcomes, but there are still contradictions and nuances, especially because studies often group all carbohydrates together rather than separating them out by food source at least, and most people can't really appreciate this. So we decided to do a little bit of research to come up with our take on carbohydrates based on the current evidence, plus how we are applying it to our meals. Today I'm going to talk to you about five ways to eat carbohydrates to maintain blood sugar balance, what's best for health, and some easy rules that you can apply every day when you eat carbohydrates so you can enjoy them as well as better understand them as well. Remember, you can watch today's podcast on YouTube. It is the simplest way to support the podcast, no cost. You can also download the Doctor's Kitchen app for free to get access to all of our recipes, and we're going to be adding low carb resources for you as well. Plus, check out Eat, Listen, Read, our newsletter that goes out every single week where I give you a recipe, something to listen to, something to read that will help you have a healthier, happier week. On to the podcast about carbohydrates and ways in which you can better enjoy them. I'm going to talk to you about five better ways in which you can enjoy your carbohydrates. There's a lot of noise online that you'll hear about why carbohydrates are bad. I think everyone wants to go on a low carb diet and there's a general understanding or a general idea that limiting carbs is a good thing. But I'm going to talk to you about why carbohydrates are a good thing and five ways in which you can better enjoy your carbohydrates. So, number one, moderate carbohydrate intake may be the best for health and longevity. We'll go into about what moderation actually means in terms of the proportion of what you eat on a 24-hour basis. And I want to link to just two studies here that I've looked at. We looked at a whole bunch. There is a lot of debate about the healthfulness of low carb diets, which may be relevant and useful for specific needs, particularly when it comes to metabolic flexibility or metabolic inflexibility. So that's a fancy way of saying those who are at risk of type two diabetes or have type two diabetes, or those who have type two diabetes. Overall, the current evidence suggests that eating a moderate amount of carbs is linked to best overall health. So there is a meta-analysis published in 2018 in The Lancet, which is a top-tier journal, and that found that lifespan was greatest amongst people who ate moderate amounts of carbohydrates. That was determined as 50 to 55% of total energy intake in a 24-hour period. Now that sounds like a lot. We're going to go into that a bit more. Compared to those who had both low carbohydrate intake and high carbohydrate intake. So there appears to be a sweet spot as per this study, the link of which is on the doctorskitchen.com show notes and in the YouTube caption. There is another meta-analysis published in Nature, again, another top-tier journal, showing that carbohydrate intake within the recommended 45 to 65% of calorie intake was not associated with an increased risk of type two diabetes and was even associated with a modest lower risk. Again, they were using different cutoffs, so around 50 to 55% of your total energy intake in a 24-hour period appears to be that sort of sweet spot. But what does moderate mean? So, in those papers, moderate intake was defined as 45 to 65% of total energy intake. So if, let's use an example, you're getting 2,000 calories a day, that translates to between 225 to 300 odd grams of carbohydrates a day. That sounds like a lot. We're going to go into that in a in a little bit more detail. The numbers are still quite vague, and I think there is this idea that everyone needs to hit this 2,000 calorie intake per day. But as we've talked about on other podcasts, your calorie intake isn't necessarily going to be a determinant of weight or your healthfulness over the long term as well. And I think the immediate sort of image that conjures up in people's minds is that, okay, 50% of my meals are going to be made up of pasta, bread, refined carbohydrates. That's not what these papers are saying, and we're going to dive into another tip about how you can better enjoy carbohydrates, and that doesn't necessarily mean the starchy carbohydrates. There's very, very distinct types of carbohydrates. So that's looking at total carbohydrate intake. And as we're going to get into it, there's a lot more than just looking at carbohydrates as a singular element in your diet. And that comes on, that brings me on nicely to number two, which is choose quality carbohydrates. Food integrity is super important here. Carbs are diverse, right? So the term carbohydrates covers a large number of different compounds that are formed by plants. So you've got everything from sugars and starches all the way down to dietary fibres, and they are all made from the same building blocks, but the way they are packaged and what we put on our plate is very, very different. So they're found in a wide range of foods, everything from refined white rice, from white pasta, from supermarket breads, which are highly, highly processed, and that's a whole other topic, all the way down to whole grains, einkorn, starchy vegetables, carrots, peas, legumes. These are all lumped together under this massive umbrella as carbohydrates. So already, without me going into any more detail, you understand the flaws in some of these big, big studies that lump carbohydrates all into one bucket. And depending on the bias of the researchers, the headline grabbing nature of papers that is sort of a necessary evil to even get media attention these days, it's very easy to manipulate some of the findings of these studies to suit a particular dietary dogma. I won't go into too much detail there, but just so you understand, carbohydrates are super, super diverse. The food source makes all the difference. So most of the discussion around carbohydrates is focused on whether we should be eating them or not, which I think is the wrong question to be asking. You want to understand that there is compelling evidence that the quality of the carbohydrates will have a much bigger impact on your health. A couple of studies. There is a systematic review of prospective cohort studies published in The Lancet, so again, another top-tier journal, that showed carbohydrates from those quality carbohydrates I was alluding to earlier, fruit, pulses or whole grain products were associated with lower mortality risk and a lower risk of cardiometabolic diseases. Whereas refined carbohydrates that we put into another bucket, so added sugars, sugar-sweetened beverages, cereals, a lot of supermarket breads, very, very refined, those are actually associated with cardiometabolic disease. There was another study, a meta-analysis of intervention studies that showed a decreased risk of cardiometabolic diseases when the intake of whole grains, pulses and fruit, so pulses, another word for legumes, beans, peas, chickpeas, my favourite legume, was increased. So again, a lower association of cardiometabolic diseases when the intake of those quality carbohydrates was included in the diet. So foods are more than just the carbohydrate label. They can contain anywhere between 1% and 60% carbohydrates in a carbohydrate type food, which means there's a lot of space for other nutrients that can tell more of the story than just the carbohydrate content itself. So the next question that people will ask me, Dr Rupy, what is a quality carbohydrate? How can I tell that this is a quality carbohydrate versus a poor quality carbohydrate? Well, a good source of carbohydrate is essentially defined as a naturally occurring food that preserves its original structure that is unprocessed or minimally processed. So prioritising the unprocessed varieties, you want to be thinking about partly milled or unrefined grains, and you want to be thinking about whole fruits and vegetables and whole legumes that haven't been refined and ground into a powder, for example. And then obviously you have your nuts and seeds as well. So those are the carbohydrates that you're really thinking about. That's the quality carbohydrates versus the other types of carbs that have a nod to what they were before, but they are highly, highly refined. The reason why, so let's dive in a little bit deeper into why this is having such a potential impact on what we see with these big meta-analyses and these systematic reviews. So carbohydrates in their natural, unrefined form also come with a plethora of other compounds that provide healthful benefits to us. Fibre, protein, vitamins, minerals, beneficial plant compounds like polyphenols, whereas the refined carbohydrates, so if you imagine white rice, for example, has a lot of that stripped out, has the fibre stripped out, has the B vitamins that is contained within the husks of that particular grain stripped out. And so what you're left with is lack of nutrients that actually has a positive influence on the body itself. Carbohydrates in their whole form also have a much more integral food matrix. Now, I want to use an analogy here. So imagine a Jenga tower before you've made any removals of the blocks themselves. A Jenga tower when it's freshly ready to be played is really nice and sturdy. So if you give it a good nudge, it's not going anywhere. If you have another Jenga tower, perhaps 20 minutes into the game and you've got loads of holes in it, it only requires a little nudge for the whole tower to be pushed over, very, very easily. That sort of structural integrity that you have with the whole block is essentially what a whole unprocessed or minimally processed carbohydrate is like. It's quite hard to break into it. It requires a lot more energy and a lot more effort, which means that the sugars that you find in all carbohydrates is going to be a lot harder to access. It's going to have a slower introduction into your bloodstream. It's going to have a less of an impact in terms of the glucose spikes that we know from my other podcast on glucose that we need to try and mitigate against. We don't want to be having these big spikes up and down. We want to be having a nice flat glucose curve. This whole Jenga-like structure is protecting the nutrients and making it a lot less accessible to the digestion process. And therefore you have that slow, gradual rise in blood glucose. The blood glucose rises is not a bad thing, but we want to try and flatten those curves so the introduction of sugars into our bloodstream where it can be transported into storage molecules, so your fat cells, your liver cells and your muscles, can be a lot more effective without the need for excess amounts of insulin. Third thing, when foods are processed into food products, there is also a harsh mechanical and sometimes thermal treatments to disrupt this fibre network, and that changes the chemical and physical properties of the foods themselves. And this modification interferes with the nutrients that will interact with your digestive processes as well. And so again, that can cause this large rise in sugar in your bloodstream, which is something that you want to mitigate against. In other words, the carbohydrates in your foods are more exposed than the carbohydrates found in unrefined or minimally processed foods. I just want to labour the point here because I think it's a a really important concept to to get your head across. I want to pull up an image here from one of the papers that me and the team looked at, which illustrates the point about the rate limiting factors that will impact how the digestion process works. And if you look at this diagram, it shows macronutrient composition, nutrient density, the form of the food, so whether it's liquid or solid, fibre, obviously has an impact. There are some physicochemical structures of foods like the osmolality, the acidity, we don't really need to go into too much detail for that. But generally you should get the idea that the form of the product will have an impact on the digestive process. And there are studies, for example, that will compare oat flour versus whole oat flakes. And the flour, even though it's exactly the same product, there is no addition to the product at all, the flour will cause a larger increase in blood glucose compared to the whole oat flakes because that starch that is in the oat flake itself is a lot more available when it's in a flour form. And so the digestion process doesn't have to work as hard to dive into that Jenga tower block because it's it only takes a nudge to get access to those sugars. So, carbohydrates, they're rolling in a big group, some positive players, some negative players, but they all get lumped into one. And it's very easy to to make an inaccurate heuristic or an inaccurate rule of thumb that all carbs are bad just from a soundbite. And the reality is, you know, the types of carbohydrates that people are consuming are the wrong types of carbohydrates. And this isn't just my opinion. There was a 2015 to 2016 survey in the US population called the National Health and Nutrition Examination Survey, also abbreviated as NHANES. They found that carbohydrates account for around 50% of total energy intake. Now that seems like that's bang on what should be associated with lower mortality risk, better health outcomes. However, when you dive a little bit deeper into what carbohydrates those are that they were referring to as 50% of the total daily energy intake, 9%, just 9% were from the higher quality carbohydrates that you know all about now, legumes, fruit, vegetables, nuts, seeds, those types of carbohydrates that are harder to digest essentially, versus the majority of carbohydrates that were in that diet, which were from refined grains, added sugars and sweetened beverages. And those kind of grains can slip into the diet even with a health label as well. So a lot of granolas, for example, a lot of flapjacks, tracker bars, energy balls, all those different things would actually fit into the refined carbohydrates, even though they are packaged and marketed as healthy. So it's very easy to slip up here on the whole versus processed carbohydrates. And that's the reason why I believe carbohydrates get a bad rap. That isn't to say that a low carbohydrate diet isn't useful as a therapeutic tool, but in general, most people would benefit from getting more quality carbohydrates in their diet. We don't have UK data, but it suggests that there is still a shift needed when it comes to where we are getting our carbohydrates from. Beyond carbohydrate quality, the body's response to carbs can also be improved by other foods on our plate. And this brings me on to the third reason or the third way in which you can better enjoy your carbohydrates. Food combinations. Food combinations are fantastic and they are very important because I don't know anyone, even the biggest potato lover, that simply eats fries on their own or simply has a cracker on its own. Most people, when they consume food, have it as part of a meal or part of a non-recipe recipe, which is how I like to have my diversity bars, for example. What we eat food with has an impact on the healthfulness of each individual element. I want to refer to just one study in this example. So this is from 2012, and they found that eating carbohydrate-rich foods with other foods that had fibre, fats and or protein can improve the body's response to the sugar contained within the carbohydrate itself. So they did a crossover study on people with type two diabetes, which I think is the most useful type of study when you're looking at the impact of food combinations in this particular example. The reason why is because you give the same people the intervention that you're looking at. So some people were given an amount of white rice with fats and protein and other fibres, and the same people after a washout period, so that's a period where you don't do anything or there's no intervention going on, were given the same white rice without the addition of those other macronutrients, the fibre, the fat and the protein. And what they found is that when eating white rice mixed with beans that have the fibre and the protein, that produced a lower glycemic response than the same amount of white rice alone. So this goes to show that in reality, there is an impact of what you eat your food with. And you can do this experiment yourself. I'm a big fan of CGMs, also known as continuous glucose monitors. I think that it gives you the ability to do some of these experiments yourself. And if you did want to do a crossover study, I would eat white rice and then I would see what my glucose responses at regular intervals, 30, 60 and 90 minutes. And then the same time the next day after doing exactly everything the same. So if you're doing this for lunch, for example, and you've had breakfast, have the same breakfast, have the same exercise regime, have the same sleep quality, if you can, try and keep that the same. And then repeat the experiment with the same rice, for example, and beans or other fats and proteins and just see what the response is. Again, at 30, 60, 90 minutes, you could be surprised at what you find out. And I think those sort of little experiments that you can do yourself are quite motivating. Let's go into some of the reasons as to why this little experiment could work for you. So dietary fibre that is found, as you'll always hear me say, in fruits, vegetables, legumes, nuts, seeds, these are resistant to the action of digestive enzymes. So if you're mixing in fibres with some of the more readily available starches, then your body is going to have to work harder to get access to the starches. So if you go back to my Jenga sort of analogy, if you've got a Jenga tower that has some holes in it, your fibre is essentially protecting some of those holes, making them a bit more stronger. So even though the Jenga tower still has holes in it, the fact that you're facilitating, supporting, plugging up some of those holes gives a little bit more structure to the entire tower, which means it's still it's not as easy to knock over. And that's the the job of your your digestive enzymes. So when it reaches the large intestine intact, it feeds the intestinal microbes as well. And these produce short chain fatty acids, which is beneficial again to metabolic health. They're beneficial for energy balance, also known as energy homeostasis, that's the fancy word for it. It also signals satiety to the brain, and it was shown that higher fibre content can actually help lower the glycemic response to a meal as per that Jenga example as well. So adding fibre to your meals has multiple benefits. It slows that glycemic response, it improves your digestion, and it feeds your microbes that then in turn create other metabolites that improve your health as well and signal satiety, which I think overall in the context of real world situations is is a really important consideration because we don't all eat in a lab, we're not all in a metabolic chamber where every single calorie can be accounted for. And in reality, we get hungry. And so if you're having something that reduces hunger, you're less likely to overeat as well. Fat, so the fat that you find in something like one of my favourite fats, extra virgin olive oil, or oily fish, I'm a big fan of nuts and seeds, these can slow down the gastric emptying process. So if you refer back to that same diagram that we were looking at from the same study in 2020, you'll see that some of the rate limiting factors on the left were the composition of the food, but then you've also got something in between the stomach and the small intestine referred to as gastric emptying. The fats in your food can slow down the digestion of carbohydrates by slowing that gastric emptying. And therefore, when you slow that process, you're giving your intestines time to break down those foods, absorb those sugars slower, and that slows the response in your bloodstream as well. So again, fats in your food are very important, not just from the perspective of slowing glucose responses, but also because they add the element, the the coat that a lot of fat soluble vitamins require for absorption themselves. Plus, they have anti-inflammatory benefits, like extra virgin olive oil, we can wax lyrical about that. We've done a whole podcast episode on extra virgin olive oil and why I'm such a big fan. It has all these different polyphenols in that are beneficial for inflammation and it's definitely one of my favourite fats. So I always sort of shudder when people suggest to others that they should be removing all sort of oils because it is a refined processed product. And yes, it is refined by virtue of what we just discussed about processing, but it is minimally processed. So you want to be looking for a cold pressed extra virgin olive oil that doesn't have that heat extraction element and actually is going to be preserving a lot of those polyphenols that we know are so helpful. Proteins. So as well as fibre and and fats, proteins that you find in meat, fish, eggs, dairy, legumes, seeds, these can also delay gastric emptying and slow down that absorption pathway as well. They can also interact with starch granules present in these starchy foods, which limits again the accessibility of enzymes in the digestive process that slows down absorption. So again, using that sort of analogy of the Jenga tower with the holes in it, these different elements can plug in those holes and make the whole structure less accessible or less prone to being knocked down as easy as well. So again, resulting in a lower glycemic response. That slight increase in protein content in people's diets can help reduce the glycemic response of carbohydrate-rich foods. And when I say glycemic response, I'm referring to the natural and expected glucose rise after you eat a meal. That is what I mean by glycemic response. I should have clarified that a little bit earlier. So, just to reiterate number three, pairing carb-rich foods with foods high in fibre, protein and fats can prevent exaggerated rises in your blood glucose and and encourage a more gradual increase. Number four, which I think I'm really excited about. I think it needs a little bit more research because there isn't too much on this, but it is eating your carbohydrates last, also known as nutrient sequencing. That's if you look up nutrient sequencing, that's probably what's going to come up in PubMed rather than another sort of colloquial name for it. So in addition to the composition of your meal, the quality of the carbohydrates that you're consuming, researchers have also looked at the impact of different foods glycemic response, which is that expected rise in blood glucose after you're consuming a meal, when they're eaten in a specific order. Recent studies have found that eating protein, fat and fibre from vegetables before eating a starchy food, so whether that's rice or whether it's pasta, can attenuate, fancy word for slow or mute, blood glucose responses by 73% compared to eating the starchy foods first, which is pretty massive. And I just want to labour the point that these studies are generally quite small. I talked about them at length in the podcast that I did on glucose responses. Um, but it is really, really interesting. And I always like to think about the elements of diet that are imprinted in cultural practices. So if you look at Japanese culture, Indian culture, Italian culture, there tends to be like an antipasti, for example. In Japan, they always have like fermented vegetables at the start. In India, we have things like pickles, we have like raw red onions and chillies that we pair with our foods. In Italy, obviously antipasti, you have these roasted red peppers before you have latter courses which have the pasta and all the deliciousness that you tend to have with, you know, refined carbs and all the rest of it. And Japanese, you know, you have the white rice, sushi rice, etc, etc. There appear to be patterns within different cultures where you're essentially preparing your digestive process, you're preparing your digestive system for the inclusion or the introduction of carbohydrates or starchy carbohydrates, refined carbohydrates, whatever it might be. So I always like to think about the evolutionary perspective on these because there is a lot of wisdom in the cuisines, as I'm learning as well from my own family and just doing a deeper dive into my own culture, but they're mirrored across the world as well, the more we look into it. There was a small study, and I just want to heighten that focus on the word small study, on adults with type two diabetes. So these are already metabolically unhealthy people who will have an exaggerated response to to sugars in the diet. Um, where they they need an ever increasing amount of insulin because insulin resistance also comes into it. And they found that glucose peaks, so that's at the top of the glucose curve after you've eaten a meal, were lower when carbohydrates were consumed last, i.e. after protein and vegetables were consumed compared to eating carbs first in a meal. And again, this was a crossover trial, so same pattern of eating, washout period where they don't do any intervention, and then another pattern of eating and they saw these responses. And the authors of this study that you can find in BMJ Open Diabetes Research and Care, we'll put the links down below as well, suggested that a carbohydrate last meal pattern may be an effective strategy to regulate glucose levels. So if you're going to be eating carbs or you're about to eat carbs, think about this as a potential strategy that is evidence-based, although there is a small evidence for it, that could attenuate those blood glucose responses. And again, this is in type two diabetes. It doesn't necessarily mean that it translates to healthier people, but I always like to think about these things through a pragmatic approach. And pragmatically, if this is effective, then it's worth a shot. And I think it's also mirrored in the pattern of eating that our ancestors have been eating according to for for millennia. And I think there's some wisdom in there that can't always be explained through the lens of a randomized control trial or an intervention. So eating a vegetable starter first, like roasted vegetables, salads, or foods rich in protein before your carbohydrates is a suggestion that I would say. Even if it is, there was a study that I've also talked about in a previous podcast where people were given a handful of almonds before eating a meal, 10 minutes before eating a meal. And again, that attenuated, muted that glucose response after eating. So it could be as simple as that if you don't want to break out your pans and, you know, start roasting some vegetables, it doesn't need to be that complicated. It can be just having a handful of nuts before you eat a carb-rich meal. So my fifth suggestion for better enjoying your carbohydrates is diversity. Diversity is the fruit of life. It is the deliciousness of variety. Carbs are diverse. You don't want to get all your carbs from one singular source. When we were talking earlier about how the sweet spot is 45 to 65%, I alluded to another study that looked at the types of carbohydrates that people are getting that total energy intake from. And it's usually refined carbohydrates. And you want to be diversifying your strategy. Almost like it's a roulette table and you're trying to go for the win and you're trying to spread your bets so, you know, one of them is going to hit. You want to spread your bets across lots of different types of carbohydrates because they're each going to be paying you dividends. They've each got a different macronutrient profile slightly. They've each got a different micronutrient profile. Some of them have more magnesium, some of them have more zinc, some of them have more vitamins. There is a plethora of different varieties that you can get from different carbohydrates. And you want to be enjoying all those different ones as well. So when people think about carbohydrates, even me, because of the exposure that I've had to the media, I think of rice and I think of pasta and I think of bread. That's not carbohydrates that you want to be focusing your diet around. Not to say you should never eat those, but you want to be thinking about fruit, vegetables, nuts. These all have carbohydrates in, they all have those starches from sugar, they all have those sugars from plants, and that's the type of quality carbohydrate you want to be focusing your your diet around. The effects of these different carbohydrates in the body also vary by carbohydrate subtypes as well. So when you diversify these different types of food, you're ensuring a variety of different health benefits. And I'll just give you some glib examples here. So beta-glucan that you find is a is a form of soluble fibre that's found in abundance in barley. And barley has been linked to a decreased level of cholesterol, total cholesterol and LDL-C cholesterol as well, which can translate into a reduced risk of heart disease. So you want to be having lots of different types of soluble fibre. You don't just want to be having barley because of that particular reason. You want to be having other grains as well. Another addition to your carbohydrate quality profile could be apples. Apples contain pectin, which is a complex polysaccharide. So it's a polysaccharide, again, is a funky word for like a a complex mishmash of all these different sugars, and they're found in the skin of apples and can contribute to the reduction of blood glucose rises after having a meal as well. So all these different carbohydrates have varied responses in the body, and you want to play that diversification strategy because there are so many benefits to be gained from having carbohydrates. When you limit carbohydrates and you're just eating proteins and fats, yes, you will be having a flat glucose curve. And yes, you might feel better in yourself and yes, you might feel better satiated because we know protein, for example, is really, really satiating. So your energy intake will go down and you'll probably lose weight. But I think as a long-term strategy, introducing carbohydrates after, let's say you're on a therapeutic diet for type two diabetes or metabolic inflexibility or insulin resistance, which are reasons as to why someone might try a low carbohydrate strategy, you want to be introducing carbohydrates at some point in the future because you're otherwise missing out on a lot of different nutrients and you may have to end up supplementing. And as I've talked about on the podcast before, you don't want to use supplementation as a strategy to replenish what you can actually get from food because there are all these other sort of entourage of other nutrients that you find from whole unprocessed food, many of which we haven't even fully elucidated yet. There are thousands of different polyphenols that you find in whole unprocessed foods. And we can go through a whole list of them, whether it's quercetin or resveratrol, luteolin, apigenin, EGCG that you find in matcha. There's so many different ones that you are going to be getting from whole unprocessed foods. So try and use that as a strategy. So those are my five better ways to enjoy your carbohydrates. Think about diversity, ensure that you're eating starchy carbohydrates last, make sure that you're thinking about food combinations, so you're not having carbohydrates on their own, particularly the the starchy carbohydrates. Make sure that you're also thinking about quality carbohydrates and moderation is definitely key when it comes to your total carbohydrate content. I really hope you found this particular podcast useful. We are going to be doing a deeper dive into other carbohydrates because I know that there are loads of other questions that you have, including questions like, you know, which carbs are better for weight loss, which of those are lowest in sugar. We'll get to those, but if you get the basics right about why carbohydrates are so important, I know this will put you in good stead. I hope you enjoyed watching this. If you are watching this, you would have seen my dog pop up her head every now and then. Um, and on the podcast, make sure you do check out our YouTube channel where you can see my smiling face and my dog's as well every now and then when she makes an appearance.
