High-Quality Diet Group Shows Up to 28% Lower Risk of Developing Dementia

Severance Hospital Team Analyzes the Link Between Diet and Dementia Risk

Professor Lee Ji-won from the Department of Family Medicine at Severance Hospital, Professor Kwon Yoo-jin from the Department of Family Medicine at Yongin Severance Hospital, Dr. Heo Seok-jae from the Department of Biomedical Systems Informatics at Yonsei University College of Medicine, and student Yoon Ji-eun's research team announced on July 4 that, based on their analysis of data from approximately 130,000 individuals in the UK Biobank, a Mediterranean or high-quality diet can reduce the risk of developing dementia by up to 28%.

Severance Hospital

Dementia is a representative degenerative neurological disease characterized by progressive cognitive decline. According to the Central Dementia Center at the National Medical Center, it is estimated that the number of dementia patients aged 60 or older in Korea has surpassed one million. However, as there is still no effective treatment available, the importance of early prevention strategies is being increasingly emphasized.

Recent studies have shown that lifestyle factors such as nutrition, physical activity, sleep, and social interaction are important determinants of dementia risk. In particular, the relationship between dietary patterns and brain health has attracted attention, highlighting the potential for dementia prevention through dietary interventions.

The research team used data from 131,209 individuals registered in the UK Biobank, followed up for 13.5 years, to investigate the association between dietary patterns?such as the Mediterranean Diet Adherence Screener (MEDAS), the MIND diet, the Recommended Food Score (RFS), the Alternative Healthy Eating Index (AHEI), and the Empirical Dietary Inflammatory Index (EDII)?and the incidence of dementia. The degree of adherence to each dietary pattern was divided into quartiles, and Kaplan-Meier cumulative incidence analysis was performed.

MEDAS, the MIND diet, RFS, and AHEI are all dietary patterns composed of healthy fats primarily from plant-based sources such as vegetables, fruits, whole grains, nuts, and fish, and are rich in nutrients with anti-inflammatory and antioxidant effects. In contrast, the EDII represents a dietary pattern composed of saturated fats and refined carbohydrates.

The analysis showed that groups with high adherence to the MEDAS and MIND diets had a significantly lower risk of developing dementia. A protective effect was also observed in groups with high overall dietary quality, such as the RFS and AHEI groups, which showed a reduced risk of dementia.

In the MEDAS diet group, the highest adherence quartile (Q4) had up to a 21% lower risk of dementia compared to the lowest quartile (Q1). In the MIND diet group, Q4 showed a 27% reduction in dementia incidence compared to Q1. In the RFS group, Q4 had up to a 28% lower risk, and in the AHEI group, Q4 had up to a 23% lower risk of developing dementia compared to Q1. In contrast, in the EDII group, which is associated with a higher risk of inflammation, Q4 had up to a 30% higher risk of dementia compared to Q1. These results were also observed in the analysis of mild cognitive impairment (MCI) risk, indicating that healthy dietary patterns have an important preventive effect even in the pre-dementia stage.

The research team also analyzed the association between dietary patterns and dementia risk according to follow-up periods of less than 5 years, 5 to 10 years, and more than 10 years. The results showed that, in both the less than 5 years and 5 to 10 years groups, the MEDAS, MIND diet, RFS, and AHEI groups all showed a significant association with reduced dementia risk, while the EDII group showed an increased risk of developing dementia. In the group with more than 10 years of follow-up, only the MEDAS and EDII groups showed statistically significant results.

Professor Lee Ji-won stated, "Through this large-scale population-based cohort analysis, we were able to confirm the association between dietary indicators and cognitive health," and added, "We expect that high-quality nutritional diets such as the Mediterranean diet may help prevent diseases like dementia and mild cognitive impairment, for which there are currently no effective treatments."

The results of this study were published in the international journal 'Journal of Nutrition, Health and Aging.'