Dodging diabetes: Is cutting carbs the key?

Speakers

Kirsten Dorans, assistant professor of epidemiology, Tulane University School of Public Health and Tropical Medicine
Andrew Yawn, assistant director of Public Relations, Tulane Communications and Marketing

 

Yawn
Welcome to On Good Authority, the podcast by Tulane University, where we bring you leading experts to talk about the issues of the day and the ideas that shaped the world. I'm your host, Andrew Yawn. We're here to talk about sugar, blood sugar. Diabetes affects more than 37 million Americans, with symptoms often going unnoticed for years. And many may not know that three times as many Americans have prediabetes, a condition where your A1C has not yet reached diabetic levels, but perhaps will if left unchecked. Thankfully, today we're speaking with Tulane assistant professor of epidemiology, Kirsten Dorans, whose research recently found that cutting carbs may be the key to keep blood sugar levels low.

Welcome, Kirsten.

Dorans
Hi, Andrew. Thanks so much for having me.

Yawn
Of course. So you're coming for America's carbs. That's a bold stance for someone living in New Orleans surrounded by the king cakes and po’boy sandwiches.

Dorans
Yeah, definitely, especially during Mardi Gras season.

Yawn
Absolutely. And for those who don't know, what happens to your body when you have diabetes?

Dorans
Diabetes occurs when the body doesn't use insulin correctly, and it can’t regulate blood sugar levels. When someone with diabetes eats carbohydrates, for instance, their blood sugar levels will spike more than they would in someone who doesn't have diabetes.

Yawn
You know, your research is important. And it found that those with diabetes, and prediabetes, who ate fewer carbs, you know, bread, rice, et cetera, were able to lower their blood sugar. That's huge. You know, what prompted this research? What should people take away from this?

Dorans
Yeah so, we know that a low carbohydrate diet lowers blood sugar in people who have diabetes, but less is known among people with prediabetes, or those with elevated levels of blood sugar in the diabetes range, but who are not on medication. So what we wanted to do was test this dietary intervention in this population.

Yawn
Tell me a little bit about this, about the study's kind of set up, you know, in terms of the guidance that you were providing and how that was organized.

Dorans
Sure. So we enrolled people who had elevated levels of blood sugar, known as A1C, and we randomized them to either receive this behavioral intervention, meeting regularly with a dietitian focusing on reducing their carbohydrate intake for six months, or to continuing on with their usual diet. And then we compared things like their change in blood sugar, weight loss, and other markers over that time.

Yawn
This study obviously picked up a lot of attention nationally, a lot of folks who reached out wanting to know more about this. How important is it for people to understand that there are some, you know, relatively easy ways to cut carbs and lower blood sugar at home?

Dorans
So I think, yeah, there are a lot of pretty straightforward ways. It can always help if someone has a dietitian or other person, health professional, who's able to help them as well. But some ways, like I mentioned before, was making substitutions can be a way to help. So I know we eat a lot of rice in New Orleans and in Louisiana, but one kind of easy substitution is cauliflower rice for that to lower carbs. We can also think, you know, instead of like a regular wrap, we could do a lettuce wrap or something like that. And another thing is just to think about portion size as well.

Yawn
One thing that surprised me a little bit, you know, obviously, diabetes is prevalent in this country. But, you know, I'd never heard of prediabetes before going over this study with you. Ninety-six million Americans may be on the path toward diabetes, and many might not know it. You know, that's, that's three times as many people as have diabetes, according to CDC numbers. You know, why is it so important for everyone to begin thinking about blood sugar, even if they don't have a diagnosis or diagnosis of prediabetes?

Dorans
Like you mentioned before, prediabetes is what happens when someone has elevated levels of blood sugar that are not quite high enough to be classified as diabetes but are higher than the normal. And so, people can have prediabetes, or even Type 2 diabetes, and not know it, they may not have symptoms initially. But we know that people with prediabetes have a higher risk of developing diabetes, but that it also can be prevented through lifestyle. So through making changes to diet and becoming more physically active as well. And so, this particular study, we just looked at, you know, one potential dietary intervention that people could make, so cutting down their carbs to lower, potentially lower their risk of diabetes. But more research would need to be done to study people in larger groups over a longer period of time to see if that would reduce risk.

Yawn
What does, what does a low-carb diet look like for you, you know, or the average American? What are some kind of easy replacements?

Dorans
Yeah, that's a great question. So it really can look a little different for everyone. In our study, what we emphasized was really having people eat more protein, seafood, things like healthy fats like olive oil and other unsaturated oils, also vegetables that are not starchy, nuts and avocados, things like that. So really trying to limit or, you know, minimize things like cereals, bread, pasta, and other high-starch or high-carb foods.

Yawn
Interesting. Yeah, I read in the study that half of the calories eaten by those who cut carbs were fats. And obviously, this study didn't get into weight loss or anything like that. But, you know, folks saw blood level, blood sugar levels improve, and they were, you know, eating these, quote unquote, good fats. You know, you kind of just touched on this, but, you know, what, what does that include? What did that look like in your study?

Dorans
So what we saw was that people did drop down their carbs a lot, so a greater percentage of their calories were coming from fats. But most of those, like you mentioned, were fats that are unsaturated and healthier, like things like, coming from things like olive oil, nuts, other things like that. People focused more on eating, eating those types of foods.

Yawn
Perhaps a recommendation of if you're looking for a snack, to maybe reach for some walnuts or something like that?

Dorans
Yeah, definitely. Yeah. So maybe eating walnuts. We actually did provide a little bit of supplemental food to people, and walnuts were some of the food that we provided.

Yawn
Absolutely. You know, the old adage, “everything in moderation.” It kind of seems like, even if you don't necessarily have a diabetes diagnosis, it may be a good idea just to think about ways to incorporate some of this stuff into the diet.

Dorans
Yeah, and I think a lot of this diet, a lot of the core components of eating, you know, eating healthy fats and eating proteins and a lot of vegetables align with a lot of different dietary approaches that are, can be healthy.

Yawn
I think of carbs, I think of the breads, I think of the rices, and these more starchy things. What are some carbs that maybe people don't necessarily think of as carbs?

Dorans
Yeah, so some other other foods that have higher carbs in them are, a lot of fruits do. So there are some that are relatively lower, but like, for example, like bananas have a good amount of sugars in them. Regular yogurt does have some carbs in it as well, which some people may not quite think of or like or milk. I think like Greek yogurt is a little bit lower in carbs if people are, you know, thinking about that.

Yawn
Yeah, this is a bit of a shot in the dark, but is there kind of like an identifier where you're like, “Oh, this is something that is starchy. This is something that's kind of grain based.”? You know, how can I maybe recognize a carb if I'm, I'm out, I'm shopping, I'm at a restaurant, and I'm trying to maybe be choosy and don't have the ability to quite look something up right away?

Dorans
So if you're out at the supermarket, you can always look at the back of the, look at the nutrition facts. But if you're at a restaurant, I think it's, I mean kind of just think about things that tend to be higher in in carbs, like breads and pasta, starches, potatoes, things like that. One, one area where there could be carbs that are kind of snuck in into things are, if you're really trying to keep your carbs low, are like in some sauces, as well. So you could, you know, kind of think about holding the sauce, you know, certain sauces, like on the side could be an option.

Yawn
Diabetes is a condition where, you know, some interesting socioeconomic correlations pop up. CDC says diabetes is more prevalent for people below the federal poverty line, more prevalent in adults with less than a high school education. Your study only worked with those who were not taking blood pressure medication. Was healthcare access a factor with that decision, or was this more about showing how people can improve their lives autonomously?

Dorans
Yes, that's a great question. So yeah, we focused on people who are not on blood glucose or diabetes medication. Importantly, nearly all, or maybe even all of the participants in our study had access to health care and had primary care providers. They were more, they had blood sugar levels that were in the range that many or some healthcare providers may not treat with medication, may, you know, focus on through lifestyle initially. So I think it's important also to think about how, or to to acknowledge that, the intervention that we provided was very intensive, and even more intensive than regularly going to the doctor because the dietitian was meeting with the participants weekly, and then monthly. And so, I think it's important for thinking about maybe potentially generalizing these findings to other populations to study whether this, how this intervention works, this type of diet works, in such situations where there may not be as much intensive support available.

Yawn
Your study also intentionally included a majority of Black participants, which historically have often gone underrepresented in medical studies. Why was this important for you?

Dorans
Yeah. So as you you mentioned, Black participants often have been underrepresented in dietary research studies. And so, I think it is really important to see whether these types of interventions work in different populations, particularly among those who may have higher risk of some of these conditions. And what we saw here is, we did see a beneficial direction of the effect of the diet on blood sugar levels in both Black and in white participants.

Yawn
What's next for this area of research in terms of, you kind of touched on this, but you know, maybe addressing this more towards folks below the pov, the poverty line or something similar?

Dorans
Most people wouldn't have access to this type of more intensive support from a nutritionist or other health professional to change their diet. I think it would be really great to test whether this, you know, these guidelines, how they could be implemented in different settings. So, you know, maybe, I was talking with someone about potentially thinking about implementing this, and like federally qualified health centers through some kind of group, like group counseling or group sessions. So we may look into that in the future, potentially.

Yawn
Do you think this research needs to go further on? What are questions that still remain for you, for others in the field?

Dorans
One thing we were talking about, how the people in the low-carb arm in this study, they, they saw weight loss in them. And so, from this particular design, we're not able to see directly how much of the effect on blood sugar levels was through calorie restriction and weight loss versus other mechanisms. So I think further exploring that, maybe in more tightly controlled trials where calorie intake is controlled a bit more, or comparing it maybe with different types of control arms would be great.

Yawn
Has this research impacted you at all? Have you changed your diet?

Dorans
I have. Yeah, I'm definitely not down to the 40 grams per day that we had recommended initially, for the first part of this study. But I do just kind of, you know, think about a little bit more if I'm going to eat, you know, like bread, or maybe I can choose an alternate, or just have a smaller portion of bread if I'm if I'm eating bread. It has changed my breakfast for sure. I used to eat a lot more oatmeal or maybe like toast, more eggs now.

Yawn
Do you have a favorite carb in particular?

Dorans
Yeah, I think probably chocolate is my favorite.

Yawn
Oh, chocolate’s a carb?

Dorans
Well it has has a good amount of sugar. And so, yeah.

Yawn
I guess you never, I think of again.

Dorans
Right.

Yawn
The breads and the rice. Our guest today has been Kirsten Dorans, assistant professor of epidemiology at the Tulane University School of Public Health and Tropical Medicine. Kirsten, thanks so much for joining us today.

Dorans
Thank you so much, Andrew.

Yawn
And thank you for listening to the latest edition of On Good Authority. For information on future episodes, please visit our website tulane.edu/on-good-authority. If you like our show, please subscribe using your favorite podcast app.