Show Notes

Read Dr. Lee’s article, “Food Insecurity and Risk of Dementia and Cognitive Impairment With No Dementia in US Older Adults,” published by JAMA Network Open online.

Learn more about Dr. Lee at her profile on the Harvard T.H. Chan School of Public Health website.

Read the Household Food Security report, “Household Food Security in the United States in 2024,” on the U.S. Department of Agriculture’s Economic Research Service website.

Listen to our episode with Dr. Beth Olson, “How Ultra‑Processed Foods Impact Your Overall Health,” mentioned at 11:00, on our website, Spotify, Apple Podcasts or wherever you listen.

Connect with us

Find transcripts and more at our website.

Email Dementia Matters: dementiamatters@medicine.wisc.edu

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Subscribe to the Wisconsin Alzheimer’s Disease Research Center’s e-newsletter.

Enjoy Dementia Matters? Consider making a gift to the Dementia Matters fund through the UW Initiative to End Alzheimer’s. All donations go toward outreach and production.

Learn about and pre-order Dr. Chin’s book, When Memory Fades: What to Expect at Every Stage, from Early Signs to Full Support for Alzheimer’s and Dementia, out June 2, 2026.

Transcript

Intro: I’m Dr. Nathaniel Chin, and you’re listening to Dementia Matters, a podcast about Alzheimer’s disease. Dementia Matters is a production of the Wisconsin Alzheimer’s Disease Research Center. Our goal is to educate listeners on the latest news in Alzheimer’s disease research and caregiver strategies. Thanks for joining us.

Dr. Nathaniel Chin: In the latest Household Food Security report from the U.S. Department of Agriculture’s Economic Research Service, it was estimated that 13.7 percent of households in the United States experienced food insecurity in 2024. Affecting one in seven households and roughly 47.9 million people, this lack of access to an affordable nutritious diet can significantly affect health. How does it then impact older adults’ health, particularly their risk for cognitive impairment? Joining me today to discuss this is Dr. Heejin Lee, a postdoctoral research fellow in the department of nutrition at Harvard T.H. Chan School of Public Health. Dr. Lee was the lead author of a paper titled, “Food Insecurity and Risk of Dementia and Cognitive Impairment with No Dementia in U.S. Older Adults,” which was published in JAMA Network Open in September 2025. Dr. Lee, welcome to Dementia Matters.

Dr. Heejin Lee: Thank you for the introduction and thank you for having me. It’s a pleasure to be here.

Chin: We’re very excited to get into this topic and your publication but, to begin, what drew you to studying dementia risk, particularly regarding nutrition and food insecurity?

Lee: To answer that, I guess I should start with where I’m from. I’m originally from Korea, South. Korea has been aging so quickly that it officially became a super-aged society just last year. Of course, well, it’s not just about Korea. Populations are aging all over the world. Population aging was something people talked about everywhere back in Korea, in the news, in the classroom, or in policy discussions, in TV shows, just everywhere. Hearing about this so often made me think more about aging-related health issues, especially cognitive health. This is a bit personal, but my grandma had some dementia-like symptoms in the last few months of her life. That actually made the issue feel much more real to me. Since my background is in nutrition, I naturally became interested in the role of diet in cognitive health. That in turn led me to study food insecurity because back in 2023, right before I graduated, I attended a conference where I heard a local congressman from Massachusetts speak so passionately about food insecurity. That’s when I actually realized that access to healthy food isn’t a given for everybody. I saw that it can be a major challenge for some people. That’s how I ended up focusing on nutrition, food insecurity and brain health. 

Chin: Heejin, thank you for sharing that and your personal connection. I’m sorry to hear about your grandmother. 

Lee: Thanks.

Chin: It also tells me the power of presentations and sharing information. You were moved and motivated by someone, a congressman speaking about it. I don’t want to go down the rabbit hole, but I am very interested. How are you defining super aging then? I mean because it seems like such an important part of your story. 

Lee: Yeah. Well, super-aged society means that more than 20 percent of the population is aged 65 or older.

Chin: Oh, okay. That’s helpful. It’s a numbers [thing]. We have important studies happening in the US about super agers — the individuals whose cognitive ability is 20 years younger than others —but that is such an important part of this conversation. There’s more people getting older, right? We see that. Food insecurity is an important part of what you’re studying. How are you defining what food insecurity is?

Lee: I think that’s a great starting point. Food insecurity basically means not having reliable access to enough nutritious food because people don’t have enough money. It’s not just about being hungry. It’s also about that constant worry, wondering if the food will run out, not being able to afford balanced meals or sometimes cutting the size of your meals because there isn’t enough money for food. They just cannot afford it. It’s also about whether healthy food is even available in your neighborhood. While this is different from choosing to eat less to lose weight or for other personal reasons, food insecurity refers to situations where people cannot access enough food because of their financial hardship. We also often classify food insecurity into two levels, low food security and very low food security. Low food security usually reflects reduced diet quality or variety but without clear reduction in how much people eat. In the past, this was often referred to as “food insecurity without hunger.” On the other hand, very low food security reflects more serious disruptions in eating patterns, where people may actually reduce the amount of food they eat. These used to be referred to as “food insecurity with hunger.” Overall, food insecurity is really about availability, accessibility and affordability, whether people can consistently afford enough nutritious food to live a healthy life.

Chin: Thank you for giving that explanation because it helps to really set the context that this is a measurable studyable characteristic and it’s not just that you don’t have access. There’s much more to it. There are criteria to this. I was unaware of the degrees and that makes a lot of sense to describe it and the way it’s now defined makes more sense than with or without hunger. 

Lee: But that is altered, by the way

Chin:  It leads me to, then, what we talk about on this podcast is brain health and brain cognition and abilities and diagnoses. Prior to your study, what was known about food insecurity, its impact on the risk of cognitive impairment and dementia? 

Lee: Prior to our study, there was already some evidence suggesting that food insecurity may be linked to cognitive decline. For example, a 2023 study by Peiyi Lu, that study showed that middle-aged and older U.S. adults experiencing food insecurity tend to have a faster memory decline over time. In that same year, Dr. Qian’s research found something similar; both low food security and very low food security were associated with a higher likelihood of dementia and faster memory decline. More recently, in 2024, another study found that food insecurity was associated with worsening cognitive function over time and greater cognitive impairment. When it comes to broader cognitive outcomes like overall cognitive impairment, which includes both cognitive impairment without dementia — we often call it CIND — and dementia, the evidence was still quite limited. Actually, there hasn’t been much research on CIND itself either. The thing is dementia develops over a long period. We wanted to catch those earlier stages like CIND to get a better picture. That’s really what led us to conduct this study. We wanted to look at a wider range of cognitive outcomes like CIND, dementia and other cognitive impairment and see how different levels of food insecurity might influence those results.

Chin: For our listeners, CIND is another description or term commonly used before the term mild cognitive impairment came out. Those are roughly the same. I guess, Heejin, one of my follow-up questions, when we look at what is available as far as that data, are there proposed mechanisms like poor nutritional content or higher intake of ultra-processed foods or lower intake of vegetables and fruits as to why there is this association between food insecurity and risk for cognitive impairment?

Lee: There are a few possible explanations for these. First off, people experiencing food insecurity tend to have poorer diet quality overall. Studies consistently show that they often eat fewer fruits and vegetables, less variety and more ultra-processed foods. Just for listeners who might not know the term ultra-processed foods or UPFs, they are basically products loaded with additives and preservatives. We are talking about things like soda, ice cream, cookies or those mass-produced packaged bread you can see at the store. These foods are typically designed to last longer and be more palatable and very affordable. Actually, it’s an easy option to go. Some studies suggest that diets high in these foods, like ultra-processed food, and low in fruits and vegetables may affect brain health through several pathways. For example, they may influence neuroplasticity, the brain’s ability to adapt and form new neural connections. They can also alter the gut microbiome. I mean, they can upset the balance in our gut and trigger things like inflammation and oxidative stress. All of these processes may influence cognitive function over time. But these are still possible explanations and the exact biological pathways linking food insecurity and cognitive health are not yet fully understood.

Chin: Heejin, actually, we just had a podcast with Dr. Beth Olson, a nutritional science professor, on ultra-processed food. If our listeners want to, you can go back to that episode too for even more details. 

Lee: Oh, that’s great.

Chin: So this is a nice follow-up. With all of that background now, can you share with our listeners how did you conduct your study? Then, of course, what did you end up finding? 

Lee: I’m glad you asked that. Well, here’s how we approached the study. For this study, we used data from a large nationally representative survey in the U.S. called Health and Retirement Study. You might be familiar with it, Dr. Chin. Anyway, it’s actually a pretty incredible resource. It’s been following tens of thousands of older adults since 1992 and it collects a wide range of information focusing on many aspects of aging from health and finances to work and cognitive function. For our specific project, we focused on data starting in 2013, which was the first time food insecurity was measured in detail in this survey. We followed participants aged 50 and older through 2020. What’s important for our research is how the Health and Retirement Study measures these cognitive abilities. Well, participants complete cognitive tasks every two years, either by phone, in person or more recently online. These tasks include things like remembering lists of words or repeatedly subtracting numbers, which help us assess their cognitive abilities. Based on these scores, people can be classified as having normal cognition, cognitive impairment without dementia or dementia. We also look at a broader category called cognitive impairment, which covers everything from CIND to dementia. For food insecurity, we grouped participants into three categories: food secure, low food security and very low food security. In our analysis, we also wanted to make sure that food insecurity came before cognitive problems, not the other way around. We excluded anyone who already had cognitive issues at the start, as well as those who developed it shortly after we began following them. Here’s what we found. People experiencing food insecurity were more likely to be younger, women and from Black or Hispanic backgrounds. They also tended to have lower levels of education and wealth and were more likely to be facing unemployment. What we really found was that the more severe the food insecurity, the higher the risk of cognitive impairment over time. For example, people experiencing very low food security had about a 79 percent higher risk of developing CIND and about a 65 percent higher risk of cognitive impairment compared to those who were food secure. We saw a similar pattern for dementia with the risk increasing as food insecurity became more severe. We also observed stronger associations among relatively younger adults. Of course, while this does not mean that everyone experiencing food insecurity will get dementia, CIND or cognitive impairment, it does mean that their risk is still higher.

Chin: Heejin, I wanted to follow up on that age finding because I think that it’s very interesting that age was this factor in this relationship between food insecurity and later-life cognitive impairment. Do you have an idea of why exactly that may be?

Lee: I think I need to answer about our findings first. When we look at the results by age, we found that the association was much stronger among adults younger than 65. For example, among adults under 65, people experiencing low food security had about twice the risk of developing CIND compared with those who were food secure. But here’s the interesting part. We did not see the same magnitude of associations among adults ages 65 and older. In that older group, the association was almost non-existent. But I want to be clear, for very low food security, the risk was significantly higher in both age groups although it was actually a bit stronger in the younger group. One possible explanation is that midlife may be a particularly sensitive period for brain health. During this stage of life, people may experience metabolic changes and psychosocial stressors like midlife crises. While we think food insecurity may further worsen diet quality and chronic stress, which might put a lot of pressure on the brain, it seems that the impact of food insecurity may vary depending on where someone is in their life course. To add to that, many studies on dementia prevention highlight midlife as a key window for intervention. This is because the impact of many risk factors such as smoking and depression can be particularly strong during midlife, although the exact biological regions are still being studied. I think this suggests that improving food security among middle-aged adults, especially before age 65, may also be an important window for preventing cognitive decline later in life.

Chin: I mean you’re really speaking to context matters for the individual and I think that’s been shown in other studies. It’s obviously being shown here about age, but, for our listeners, your study considered other potential contextual factors that could impact the result and we call that confounding variables. But you looked at marital status, employment status, race, educational background, total net worth. Then there were other things like lifestyle behaviors like exercise, smoking, alcohol intake, even BMI, to get a sense of whether it truly was food insecurity. Did your findings change at all when you included those other important contextual variables in your model?

Lee: Oh, yes. That’s a really important point. We have to be careful because food insecurity is often linked with other factors like lower education. Since education is a well-known risk factor for cognitive impairment, we don’t want to confuse its effect with food insecurity. In our study, we looked at these step by step. We tried to take a lot of different factors into account, starting with demographic and socioeconomic status, then lifestyle behaviors such as smoking, alcohol use and physical activity, and finally health conditions like cardiovascular disease, diabetes, cancer and depressive symptoms. This allowed us to get a clearer picture of the role of food insecurity itself. As expected, when we took these factors into account, the association became a bit weaker. But the key takeaway is that the link between food insecurity and cognitive impairment remains significant even after accounting for all of these factors. For example, the 79 percent higher risk of CIND that I mentioned earlier that already accounted for these potential confounding factors. To add to that, as I mentioned earlier, food insecurity is often linked to poorer diet quality. In one of our previous studies, we also found that people experiencing food insecurity tended to have lower Mediterranean diet scores and other diet scores as well, meaning they have lower overall diet quality. I think some might ask, is this just about diet rather than food insecurity itself? Well, we didn’t include this in the paper, but when we additionally accounted for the Mediterranean diet score, the results were actually almost the same, differing by only two decimal places. This tells us that food insecurity may have its own independent impact on cognitive health.

Chin: Well, that’s a great way of ending that answer too because I was wondering about if it’s the diet or not. I always like hearing information not presented in the paper. Thank you, Heejin. Now, some of our listeners though, Heejin, they may be experiencing some food insecurity in their own lives. Based on your work in the field, are there any organizations or resources that you would recommend people look into if this is their situation?

Lee: Oh yeah, that’s a really important question and thank you for asking. At the local level, food banks can be a very helpful resource. For example, here in Boston, we have organizations like the Greater Boston Food Bank and most communities have similar food banks or networks that connect people to local food pantries or sites, which provide meals right in their own neighborhoods. These organizations can also help people apply for programs like SNAP, the Supplemental Nutrition Assistance Program, which is a federal program that helps low-income households purchase food. The application process can sometimes be a bit complicated, but food banks often help with things like screening for eligibility and guiding people through the process. If approved, they would get monthly benefits to purchase food at their local grocery store. One challenge though is that many people who are actually eligible for SNAP don’t end up enrolling in the program, especially among older adults. But research suggests that among people who qualify for SNAP, those who participate may experience better health outcomes such as slower memory decline compared with those who are eligible but not enrolled. I really believe local organizations are key. They help people figure out what resources are out there and assist them through the application process. Many healthcare systems are now screening for food insecurity and offering food as medicine programs. When they complete a brief questionnaire on food insecurity at their next visit, that’s a good time to talk with their doctor about their social needs and to ask whether there are hospital-based programs that could help them with food insecurity and also with managing any chronic diseases they might have. If you are finding it hard to get the food you need, I would really encourage you to reach out to these local organizations and health care systems and take advantage of these resources. It’s a practical step you can take for your health.

Chin: Well, thank you for sharing that, Heejin. I think that’s so important that people know where to go, where to look, and local being one of those great — start local and look at your community organizations. 

Lee: Yep, that’s the first step.

Chin: To end, and transitioning back to your research, where do you hope this field goes? Where do you hope your research is going?

Lee: That’s really the big picture question. Well, in our previous study, we observed a link between food insecurity and poor diet quality. In fact, this pattern was even worse among people who experience food insecurity for longer periods of time. One of my next questions would be whether longer exposure to food insecurity further increases the risk of cognitive impairment over time. If that’s the case, it also raises an important question for policy. If we can reduce food insecurity earlier or prevent chronic food insecurity, could that help slow down cognitive decline later in life? It would be very interesting to see whether programs or interventions that improve food security might also directly benefit various aspects of cognitive health. I want to continue exploring how addressing food access and diet quality can protect our brains in the long run. Well, after all, we are all getting older. I hope this research helps find ways for all of us to stay mentally sharp as we age.

Chin: Well, I’m excited about your work, Dr. Heejin Lee, and thank you for being on this podcast today and sharing more about food insecurity and its risks for contributing to cognitive impairment. I certainly hope to have you on after more of your work is published.

Lee: Thank you. I really loved the chance to talk about my work here and I’d like to thank my wonderful collaborators and my mentor Dr. Leung for always being so supportive of me and thanks so much for having me today. I really enjoyed our conversation today.

Outro: Thank you for listening to Dementia Matters. Follow us on Apple Podcasts, Spotify or wherever you listen. Or tell your smart speaker to play the Dementia Matters podcast. Please rate us on your favorite podcast app. It helps other people find our show and lets us know how we’re doing. If you enjoy our show and want to support our work, consider making a gift to the Dementia Matters Fund through the UW Initiative to End Alzheimer’s. All donations go toward outreach and production. Donate at the link in the description. Dementia Matters is brought to you by the Wisconsin Alzheimer’s Disease Research Center at the University of Wisconsin–Madison. It receives funding from private, university, state and national sources, including a grant from the National Institutes on Aging for Alzheimer’s Disease Research Centers. This episode of Dementia Matters was produced by and edited by Caoilfhinn Rauwerdink. Our musical jingle is “Cases to Rest” by Blue Dot Sessions. To learn more about the Wisconsin Alzheimer’s Disease Research Center, check out our website at adrc.wisc.edu and follow us on Facebook and Twitter. If you have any questions or comments, email us at dementiamatters@medicine.wisc.edu. Thanks for listening.