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[00:00] Next time you sit down to dinner, should you eat the bread first or save it for last? Some social media influencers claim that simply rearranging the order in which you eat foods can dramatically improve blood sugar control. So today we're gonna take a look at the science behind that idea and whether it really makes a meaningful difference. Hello, I'm Monica Reinagel, and you're listening to the Nutrition Diva Podcast, a show where we take a closer look at the latest nutrition news, trends, and research, and answer your food and nutrition questions. And today's episode was suggested by Cynthia, who's been seeing a lot of posts on social media claiming that if you eat foods in a specific order, such as eating your vegetables or your protein first, and saving the carbohydrate foods for last, you can improve your blood sugar control. But she's not sure whether the sources behind those claims are reliable. And it's a great question because there actually is some research on this idea. But as is so often the case, the details really matter. And the first detail that matters is who we're talking about. A lot of the studies on meal sequencing were done on people with type 2 diabetes or pre-diabetes, where the insulin response is already somewhat impaired, meaning that the body has a harder time keeping blood glucose within a normal range after a meal. And for these folks, strategies that slow the digestion and absorption of carbohydrates can make a noticeable difference in how high their blood sugar rises. But this is where the social media conversation often misses the mark. It does not necessarily follow that it will work the same way in people without diabetes. Because for these people, glucose regulation isn't broken. The body is already pretty good at bringing blood sugar back into a normal range after a meal. This is something I talked about a little bit more in episode number 638 about the trend of continuous glucose monitors, or CGMs, being used by people who don't have diabetes. These devices have been designed and validated for people whose blood sugar regulation is impaired. When used by people without diabetes, the same numbers can be much harder to interpret, and they may be misleading. And here's one more thing that the influencers often misunderstand. Eating as if you already are diabetic does not reduce your chances of becoming diabetic. For example, contrary to popular lore, eating sugar does not directly cause insulin resistance or increase your risk of developing type 2 diabetes. Body composition and lifestyle habits, as well as genetics, actually play a bigger role than the amount of sugar in your diet. And it's also worth noting that even for those who do have diabetes, the order that you eat your foods in is just one of many factors that are going to impact your blood sugar response, and it may not even be the biggest one. For example, physical activity can have a surprisingly powerful effect on glucose regulation. Even 10 minutes of light movement after a meal can help your muscles take up glucose from the bloodstream. The total amount of carbohydrate in the meal also matters a lot, and so does the structure of the food itself, so whether it's been milled or pulverized or liquefied and so on. So with that context in mind, let's take a look at what researchers have actually tested. Most of the studies on this topic use a pretty simple design. Participants eat the exact same meal on different days, but they eat it in a different order. So on one day, they might eat the bread or the potatoes first, and then the vegetables or the proteins second. Then on another day, they eat the vegetables or protein first and they save the carbs for last, and researchers then measure how their blood glucose levels change after the meal. And when you look at those experiments, especially the ones involving people with type 2 diabetes, a fairly consistent pattern emerges. Eating the vegetables or the protein foods first, and the carbohydrates last, does tend to slow the rise in blood sugar after the meal, and also reduce the peak glucose level. And researchers think this happens for a few different reasons. One mechanism involves gastric emptying, and that's simply the rate at which food leaves the stomach and enters the small intestine. Fiber, protein, and fat all tend to slow this process down. So if those foods arrive in the stomach first, they can delay the delivery of carbohydrates to the intestines, and that slows how quickly the glucose is absorbed. Another factor involves the release of gut hormones, sometimes called in-cretins. So when nutrients arrive in the intestine, or foods arrive in the intestine, those hormones signal the pancreas to release insulin, and also help to slow digestion. So when you start a meal with protein or fiber, it may trigger some of those signals earlier, which can help moderate the glucose response when those carbohydrates arrive later. But the next thing we need to consider is just how big a difference this makes, because statistically significant is not always the same as clinically meaningful. As I said earlier, in people with type 2 diabetes, these studies often show noticeable reductions in the early glucose spike after a meal when they eat the carbohydrates last. Translation, blood sugar may not go up as fast or as high. But within a couple of hours, it's really often hard to see a difference between the folks who ate the carbs first and those who ate them last. And that suggests that the sequencing of the foods does change the shape of the glucose curve, but it may not dramatically change the total amount of glucose exposure. And that helps to explain why people who practice meal sequencing over a longer period of time see only very modest effects on their A1C. That's the blood measurement that reflects average blood sugar over several months. So for people with diabetes, meal order may be a useful tool for managing post-meal blood sugar spikes, but for longer term blood sugar management, it's really just one strategy among many. Now the findings in people who do not have diabetes, they look a little different, which given what we've already talked about, that shouldn't surprise you. Some studies have tested the same meal sequencing strategies in people with normal glucose regulation. And while they sometimes still see small differences in that early glucose response, the effects tend to be smaller and also shorter lived. In other words, the system is already doing its job, and hacking the meal order doesn't really have a whole lot of impact. So here are my takeaways for Cynthia and for anyone else who might be wondering about this. If you have diabetes or pre-diabetes, meal sequencing may be a useful fine tuning strategy for better blood sugar management. So eating your vegetables or your protein first, and saving the carbohydrates for later in the meal, may help blunt that early spike in blood sugar that happens after you eat. But when it comes to glucose control, you have much bigger levers to pull. Regular physical activity, especially moving your body after meals can have a very powerful effect on how your muscles are going to take up glucose from the bloodstream. The total amount of carbohydrate that you eat also has a really big influence on your blood sugar, and the type of carbohydrates matters as well. Less processed foods that contain fiber and more intact starches tend to be absorbed more slowly than highly refined carbohydrates. For people who don't have diabetes, the evidence suggests that meal sequencing doesn't appear to have much impact on long-term glucose regulation or on future diabetes risk. That doesn't necessarily mean that the strategy has no value. Sometimes, the benefit may be more behavioral than biochemical. So for example, if eating your vegetables and your protein first, means that you're more likely to actually eat them before you get full or before the bread basket steals the show, well, that could really improve the overall nutritional quality of the meal. And by the same token, if saving the refined carbohydrates for last also means that you end up eating a bit less of them, that could also be beneficial. But in both cases, the advantage isn't really about the order in which the foods are reaching your digestive system. It's more about what and how much you ultimately end up eating. Whether or not you have diabetes though, one thing that meal sequencing doesn't do is make those carbohydrates somehow free. Eating them last is not a license to eat more of them than you otherwise would. For all practical purposes, those carbohydrates are still going to count the same way they would if you ate them earlier in the meal. Thanks to Cynthia for her great question. If you have a food or nutrition question you'd like me to untangle on an upcoming episode, you can email it to nutrition at quickanddirtytips.com. If you'd like to find out about having me present at your next event, you can learn more at wellnessworkshere.com. Nutrition Diva is a Quick and Dirty Tips podcast. Holly Hutchings is our director of podcasts. Steve Riekeberg is our audio engineer. Morgan Christensen heads up podcast operations and advertising. Rebecca Sebastian is our manager of marketing and publicity. Nat Hoops is our marketing operations assistant, and Maram El-Nagiv is our podcast associate. Thanks to all of them, and thanks so much to you for listening.