The 2019 recipient of the American Diabetes Association Kelly West Award for Outstanding Achievement in Epidemiology talks about the most pressing questions in the field of diabetes research, nutrition, and the future of diabetes treatment.
Dr. Elizabeth Mayer-Davis, chair of the Department of Nutrition at the University of North Carolina at Chapel Hill and co-chair of the SEARCH for Diabetes in Youth study has focused her entire career, an impressive one at that, on better understanding diabetes to improve outcomes for patients. This mission has led to hundreds of papers and appointments to public health and nutrition advisory committees. Despite her long list of accomplishments, Dr. Mayer-Davis is incredibly down to earth. When I confess I am a bit starstruck, she laughs. “I’ve just been chipping away,” she says.
Dr. Mayer-Davis’s interest in diabetes began early. “Something close to high school,” she says. “Early on, I was interested in terms of the science and…all of the human cost, the clinical, behavioral, social, cultural issues, and what it means to an individual who has to manage this disease every single day. I did have a friend in high school who was diagnosed with type 1 diabetes. As I look back, that is the point in time that I remember very clearly following his experience.” For her, part of the draw was the science, which she calls “magical”. The other seems to be a deep caring for the impact the disease has on both an individual’s long-term health and daily experience. Dr. Mayer-Davis is also concerned with the experience of “very vulnerable populations of people…particularly people of underrepresented populations, minority populations…that experience, in the case of type 2 increased risk, in the case of type 1 much worse outcomes in terms of glycemic control and other outcomes.”
Diabetes is such a complex, multifactorial disease in terms of risk, etiology, patient experiences, and health outcomes. With so many unknowns, how does a researcher approach such a vast challenge? To Dr. Mayer-Davis, the key is “to be very clear on what the most important research question is. What are the gaps in the literature? What are the gaps that are the most likely to actually improve outcomes for people if they are filled?” Defining the question to help populations is an art and a science, according to Mayer-Davis. After that, the challenge is to design the right study to answer your question. There’s a deep thoughtfulness to her approach. Beyond selecting the right population, datacollection, measurement, and biomarkers, Mayer-Davis stresses the importance of collaboration. “We’ve learned a lot,” she says, “but we have so much yet to know, and nobody can know even a fraction of everything. It’s about having the right team.”
I’m eager to know what Dr. Mayer-Davis thinks are the most important questions in diabetes research right now. “Two things,” she says. “One, there is a discrepancy in terms of having poor markers of glycemic control…for patient groups other than non-hispanic whites. So that’s a really important area of concern.” She calls the second question, the emerging issue “of overweight and obesity in type 1 for youth and young adults…a very tricky area. It’s not the same as in any other populations, because you have energy that’s regulated in a particular way in type 1 diabetes, and you have insulin dosing, and related behaviors through the day…There are a lot of clinical behavioral and metabolic differences that make overweight and obesity a tough problem in type 1 diabetes. It’s complicated and it’s difficult to manage.” These are certainly significant issues and major research undertakings. Fortunately, Mayer-Davis is on it. Her “team has a grant now…looking for some strategies for weight management specifically in type 1 diabetes. That’s an area of work we will be engaged in for quite some time. We’re looking at dietary and behavioral strategies that we hope may be helpful for people who want to address weight at the same time as managing their glucose. You can’t do one without the other. You have to have approaches that take care of both.”
Diet can be a hotly-debated piece of diabetes management and Mayer-Davis is no stranger to this subject. A registered dietician, she’s worked directly with patients with diabetes, co-authored numerous nutrition therapy recommendations, and was even appointed to the 2020 Dietary Guidelines Advisory Committee by the U.S. Departments of Agriculture and Health and Human Services. With all the different diets touted as beneficial for diabetes or weight loss, Mayer-Davis admits it can be very confusing for people to decipher all the information out there and much of it is not well-supported. “People are always talking about glycemic control and weight,” she says, “but even if you’re just looking at glycemic control, there are very few data from good studies to really look at say the keto diet, or even just moderately reduced carbohydrate diets. It may be the case that a modest, reasonable reduction of carbohydrate may be beneficial in terms of glycemic control. But really what’s needed are well-conducted studies that are done over a long enough period of time, with appropriate measures of adherence to the diet, acceptability of the diet, and a range of outcomes preferably from continuous glucose monitoring not just A1C. Right now, we don’t have the data to make a grand statement.”
Dr. Mayer-Davis is trying to address this lack of data. In the, protein and leucine were associated with reductions in A1C and carbs were positively associated with higher A1C. According to Mayer-Davis, “For the type of study that it was, I’m confident in those results and those results are consistent with a low carbohydrate diet being consistent with better glycemic control measured by A1C. Still, that wasn’t a clinical trial where you have a defined intervention and continuous monitoring, where you can look at time in range, occurrences of low blood sugars or over target, and really using those more precise interventions and measurements to get better at the questions. It is suggestive, but that’s where we are.”
Dr. Mayer-Davis acknowledges that nutrition is a key piece of a complex puzzle. About the current challenges for people with type 1 diabetes, she says, “The reality is that in this last decade or two especially, we’ve had amazing advances in terms of insulin pumps, hybrid close loop, continuous glucose monitoring, kids staying on their parents’ insurance…in spite of all of that, we’re not doing any better in this country with regard to glycemic control. So why is that? It’s not just about available drugs and devices. This is about how people can actually manage their diabetes in their day to day experience. Taking advantage of the technology is a tremendous challenge.”
Looking ahead, I ask Dr. Mayer-Davis what the ideal future of diabetes treatment looks like five, ten years from now. “Wow,” she says. Laughing when I admit it’s a tall order. “It is a tall order. What I’m thinking about first is if we could implement what we already know how to do. That has to do with health policy, insurance coverage, education, all of the really policy driven aspects, and not just education for patients and families, but support for them to be able to manage their diabetes. I think all of those social determinants for health and health policy, really need to come along, in these next few years, so that we can make sure that patients are able to take advantage of the technology that we have. On a longer time scale, of course, I, like everybody, truly want a cure…that’s obviously what we want. But there’s a long time between now and then. So, it’s figuring out [ways to better support people with diabetes]… alongside that, improving the advice that we can give on nutrition as a function of conducting the right studies. That kind of combination is what’s needed while we are waiting for the day—and I do think this day will come [but] we’re too far away from it to get complacent.” Until then, Dr. Mayer-Davis has no plans to stop “chipping away”; she gains inspiration and energy from her students, colleagues, and people with type 1 diabetes who participate in their studies. Ultimately, she says, “we are making progress. It is slow, and I’ve been doing this a long time, but that’s okay. The people in the studies, the families, the parents, the students, and sometimes students themselves who have type 1 diabetes bring the inspiration. And the progress that we are making to move all of this forward.”