Anti-Inflammatory Diet May Benefit Older Adults at Higher Dementia Risk

Can your diet affect your risk of developing dementia?

Several large studies have already shown that eating a high-quality diet is associated with a lower risk for developing overall dementia and Alzheimer’s disease in the general population. But what about if you are already at risk for developing these types of conditions?

In a new study, led by researchers from the Karolinska Institutet and Stockholm University’s Aging Research Center, dietary information was combined with blood-based biomarker data to assess how food intake may impact dementia risk in older adults at higher and lower biological risk for Alzheimer’s and other neurodegenerative conditions.

The results suggest that higher diet quality is indeed linked to lowered dementia risk in low-risk populations. However, in those at elevated risk, only eating a diet with low inflammatory potential was seen to consistently lower the risk for dementia. These results highlight the importance of targeted dementia prevention strategies, the researchers say.

The link between diet and neurodegeneration

A person’s diet is an important modifiable lifestyle factor that is relevant to many different types of health conditions; for example, eating more saturated fats may increase cardiovascular disease risk, while eating more fiber may reduce it.

“Diet may be linked to brain health through several pathways, although we did not test mechanisms directly in this study. Previous experimental and epidemiological research has suggested links between diet and several biological processes that are also relevant to dementia risk, including vascular and cardiometabolic health, systemic inflammation, oxidative stress, insulin resistance, lipid metabolism, and possibly gut–brain interactions,” study first author Anja Mrhar told Technology Networks. Mrhar is a research assistant and PhD candidate at the University of Ljubljana, Slovenia, who is also affiliated with the Aging Research Center at the Karolinska Institutet, Sweden, as a visiting researcher.

Rather than measuring the effects of specific nutrients or food groups, the new study assesses overall dietary patterns. Three patterns were examined: the Alternate Mediterranean Diet (AMED), Alternative Healthy Eating Index (AHEI), and reversed Empirical Dietary Inflammatory Index (rEDII). Higher adherence to each dietary pattern indicates better overall diet quality.

“Dietary patterns are of interest because they better reflect how people actually eat,” Mrhar explained. “Foods and nutrients are not consumed in isolation, and their combined effects may be more relevant for complex outcomes such as cognitive aging and dementia than single nutrients alone.”

This dietary information was assessed using data from the Swedish National Study on Aging and Care in Kungsholmen (SNAC-K), a cohort study that recruits local participants aged 60 or over and follows up every 3-6 years to assess various markers of aging. This includes administering a 98-item questionnaire regarding diet and food frequency, blood tests to assess relevant biological markers, cognition tests, and an array of other clinical, neurological, and psychiatric examinations.

“In our analysis, we used repeated dietary assessments from baseline and up to two follow-up visits over the first six years of the study. This allowed us to estimate cumulative average diet quality, which can provide a more stable picture of habitual diet than relying on a single dietary measurement,” said Mrhar.

The study also looked at a range of blood-based markers that are associated with Alzheimer’s disease or dementia, including phosphorylated tau at threonine 217 (p-tau217), neurofilament light chain (NfL), and glial fibrillary acidic protein (GFAP). These biomarker levels were used to define the groups at higher or lower biological risk for neurodegenerative conditions.

“These biomarkers reflect partly different biological processes related to dementia risk,” Mrhar added. “p-tau217 is linked to Alzheimer’s disease-related pathology, NfL reflects neuronal injury, and GFAP reflects glial activation or damage.”

Low-inflammation diets linked to reduced dementia incidence in high-risk groups

During the 15-year total follow-up period, 240 of the 1865 participants included went on to develop dementia, according to medical records, clinical assessments, or death certificates.

Analysis revealed that higher diet quality was associated with lower dementia risk and a delayed onset of dementia across the entire cohort—including in those with elevated levels of p-tau217, NFL, and GFAP.

However, this association did vary across dietary patterns. Associations between dementia and adherence to the AMED and AHEI diet patterns were primarily seen in the low-risk group. In the high-risk group, adherence to the low-inflammation rEDII dietary pattern showed the most consistent association with lowered dementia risk.

While each dietary pattern does share some elements—promoting the consumption of fruits, vegetables, and whole grains while discouraging processed meats and sugar-sweetened drinks—they each highlight very specific elements relating to diet quality.

“Compared with the EDII, the Mediterranean diet places more emphasis on foods such as fruits, legumes, nuts, whole grains, and fish, and it also reflects the relative balance between unsaturated and saturated fats. By contrast, the EDII was specifically designed to capture the inflammation-related dimension of diet, rather than adherence to a traditional regional dietary pattern,” Mrhar explained.

“In our study, we used the reversed version of the EDII—the rEDII—where higher scores indicate a dietary pattern with lower inflammatory potential. In practical terms, this reflects a combination of foods and beverages that, in previous research, has been linked to lower levels of inflammatory markers. In the EDII framework, this includes, for example, higher intakes of vegetables, tea, and coffee, and lower intakes of red and processed meat, refined grains, and soft drinks. However, it should not be interpreted as a simple checklist of “anti-inflammatory foods” or as a specific prescribed diet.

“Importantly, the EDII does not completely overlap with the Mediterranean diet or with standard healthy eating indices. This may help explain why the dietary pattern with lower inflammatory potential showed different associations with dementia risk compared with Mediterranean-style eating and general healthy eating in our study,” Mrhar said.

Dietary effects on dementia risk may vary

The differing associations between the low- and high-risk groups and each dietary pattern should underscore the importance of dietary interventions for dementia, the researchers write, as well as the need for developing personalized dietary interventions for use in clinical practice.

“Our findings suggest that associations between diet quality and dementia risk may not be uniform across all older adults. A person’s underlying biological risk profile may matter,” Mrhar noted.

“In our study, the AMED and the AHEI were more clearly associated with lower dementia risk among people with lower biomarker levels. In contrast, the dietary pattern with lower inflammatory potential showed the most consistent associations among people with elevated biomarker levels, including biomarkers linked to Alzheimer’s disease-related pathology, neuronal injury, and glial activation.

“This may be relevant for future intervention studies on diet and neurodegeneration. Such studies may benefit from incorporating biomarkers to identify whether certain dietary approaches are more relevant for specific biological risk profiles. It also suggests that different dimensions of diet quality—for example, Mediterranean-style eating, general healthy eating, or inflammatory potential—may not capture the same biological or clinical information.”

The researchers do note several important limitations of this work. Firstly, the observational nature of the study means that these findings cannot prove causality and “should be interpreted as observational associations,” Mrhar advised. “They do not prove that diet changes brain pathology or prevents dementia.”

The self-reported nature of the dietary information is also a limitation; though the use of repeated dietary assessments can help to reduce some measurement or recall errors, diet was not measured continuously throughout the follow-up period.

“Dietary patterns capture overall diet quality but do not allow us to identify exactly which individual foods, nutrients or combinations of those may be driving the associations,” Mrhar added. “Further studies are needed to confirm the findings and to clarify whether specific dietary changes can reduce dementia risk in people at elevated biological risk.”

“These findings need to be replicated in other populations. Future studies should ideally include repeated measures of diet, repeated biomarker assessments, more diverse study populations and trial designs. This would help determine whether modifying diet can influence dementia risk among people with elevated biological risk.”

Reference: Mrhar A, Carballo-Casla A, Grande G, et al. Diet quality and dementia risk in older adults with Alzheimer pathology. JAMA Netw Open. 2026;9(6):e2620254. doi: 10.1001/jamanetworkopen.2026.20254

About the interviewee:

Anja Mrhar is a research assistant and PhD candidate in biosciences–nutrition at the University of Ljubljana, where she obtained a Master’s degree in nutrition science in 2021. Her research focuses on the topic of diet quality related to aging, with a particular focus on eating behavior, eating patterns, cognitive decline, and dementia in older adults. Her current work involves close collaboration with the neurology clinic at the University Medical Center Ljubljana, including involvement in interdisciplinary projects related to dementia prevention, cognitive health, and public awareness.

 

Since 2024, Mrhar has been affiliated with the Aging Research Center at Karolinska Institutet as a visiting researcher in Davide Liborio Vetrano’s research group, where she studies the relationship between dietary patterns, biomarkers of neurodegeneration, and dementia risk through epidemiological research.