Four popular diets may reduce dementia risk
Click Here to Manage Email Alerts
Key takeaways:
- Greater adherence to a healthy plant-based diet or Mediterranean diet, among others, was linked to larger brain volumes.
- The findings highlight the benefits of a healthy diet for dementia prevention.
Following a healthy plant-based diet, Mediterranean diet, the MIND diet or having a high recommended food score at midlife was associated with a reduced risk for dementia, according to research in the American Journal of Clinical Nutrition.
Previous studies on connections between dementia risk and dietary patterns are limited and inconsistent, Jingyun Zhang, a postdoctoral research associate with Zhejiang University School of Medicine in China, and colleagues wrote.
“There were more than 55 million people living with dementia worldwide in 2021, and this number is expected to increase by 10 million per year,” they wrote. “Dementia increases the risk of poor patient-centered outcomes, which include CVDs, disturbed emotions, death, depression and limited social interactions. Thus, proper preventive and management strategies are critical due to the lack of effective treatments for dementia.”
Zhang and colleagues conducted a study to assess the associations of midlife dietary patterns with brain structures and incident dementia.
The researchers evaluated the prospective associations of four healthy dietary pattern indices — the healthy plant-based diet index (hPDI), Mediterranean diet score (MDS), recommended food score (RFS) and Mediterranean-Dietary Approaches to Stop Hypertension Intervention (DASH) Intervention for Neurodegenerative Delay Diet (MIND) — with incident dementia. They identified dementia using linked hospital data of 11,684 people from the U.K. Biobank. The researchers then used linear regressions to investigate cross-sectional associations of these dietary pattern indices with brain structures.
The hPDI is an “innovative dietary pattern index” that emphasizes the intake of healthy plant foods linked to improved health outcomes. Recent research has indicated that this dietary pattern may lower the risk for mortality and major chronic conditions and has low greenhouse gas emissions.
The MDS is a nutrient- and food-based nine-item score that reflects Mediterranean diet adherence. The Mediterranean diet has been named best overall diet for six consecutive years and has been linked to several health benefits such as reduced risk for CVD, adverse pregnancy outcomes and total mortality.
The RFS measures overall dietary patterns based on the intake of five food components the Dietary Guidelines for Americans recommend. Finally, the MIND index is a combination of the DASH diet and Mediterranean diet that specifically focuses on brain health.
Zhang and colleagues found that greater adherence to hPDI, MDS, RFS and MIND was individually linked to larger brain volumes in specific regions. These findings, they wrote, provide a comprehensive picture of the consistent associations between midlife dietary patterns and brain health and highlight the benefits of a healthy diet for dementia prevention.
In the average 9.4-year follow-up, 0.42% of participants developed dementia, and all dietary patterns offered protective effects against incident dementia, but the associations were not statistically significant, according to the researchers.
“We speculate that a potential mechanism for the benefit of healthy diets in preventing dementia is that adherence to healthy diets may increase brain volume,” they wrote. “The most extensively influenced regions include the parietal and temporal cortices and the hippocampus.”
When it came to brain structure, the researchers found that higher dietary pattern indices were significantly linked to larger regional brain volumes, including volumes of the hippocampus and thalamus and volumes of gray matter in the parietal and temporal cortices.
“These findings highlight the importance of midlife dietary patterns in maintaining brain health and thereby preventing dementia,” Zhang and colleagues concluded. “From a public health perspective, preventive and interventional dietary strategies could counter the growing burden of dementia in aging populations, which may be effective even in resource-limited settings.”