Study Suggests Healthier Plant-Based Diets Could Reduce Dementia Risk

The research monitored nearly 93,000 adults over an average of 11 years. Participants included diverse groups such as African American, Japanese American, Latino, Native Hawaiian, and White individuals, with an average starting age of 59. Throughout the study, more than 21,000 participants developed Alzheimer's or another type of dementia.

Researchers analyzed the quality of plant-based diets, distinguishing between healthful and unhealthful options. A healthful plant-based diet consists of whole grains, fruits, vegetables, nuts, legumes, and vegetable oils, along with drinks such as tea and coffee. In contrast, an unhealthful plant-based diet tends to include more refined grains, sugary foods and beverages, fruit juice, and potatoes, often consumed as fast food or in processed meals. The research did not specifically examine vegetarian or vegan diets.

After adjusting for variables such as age, physical activity, and diabetes, the study found that participants who adhered closely to a healthful plant-based diet had a lower risk of developing dementia. Conversely, those with diets leaning towards unhealthful plant-based foods exhibited a higher risk.

Notably, the study also explored how dietary habits evolved over time. Participants whose diets shifted toward unhealthful plant-based foods during the study period faced an increased risk of dementia, while those moving away from such diets experienced a lower risk.

“Plant-based diets have been shown to be beneficial in reducing the risk of diseases like diabetes and high blood pressure, but less is known about the risk of Alzheimer’s disease and other dementias,” stated study author Song Yi Park, PhD, from the University of Hawaii at Manoa. “Our study found that the quality of a plant-based diet mattered.”

It is important to note that while the study establishes an association, it does not prove a direct causal relationship between diet and dementia prevention. Self-reported dietary information may also limit the accuracy of the findings. Nevertheless, the results suggest that opting for healthier plant food choices and minimizing heavily processed options could potentially support better brain health as individuals age.