A new study has identified five nutrients linked to a lower risk of dementia in older adults. The research followed more than 6,200 U.S. adults aged 50 and older for seven years to examine how 101 different dietary nutrients relate to dementia risk.
About the Study
Researchers asked participants how often they ate 163 foods and beverages over the previous year. From those responses, the team analyzed each nutrient individually and created a composite score to see how combinations of nutrients affected risk. Each participant also took a cognitive assessment, and a person close to the participant answered questions about that person’s memory.
Five Protective Nutrients
The study found that five nutrients in particular were protective against dementia. These include isorhamnetin, a plant flavonol with anti-inflammatory and neuroprotective effects. Some early research suggests it may reduce the buildup of amyloid-beta, a protein linked to Alzheimer’s disease. Dietary fiber, a carbohydrate that feeds gut bacteria and supports cognitive function, was also protective. Two forms of vitamin E—beta-tocopherol and beta-tocotrienol—were associated with lower risk due to their antioxidant activity. Manganese, a trace mineral essential for enzyme function and brain energy metabolism, also showed protective effects.
Food sources for these nutrients include onions (especially red), pears, apples with skin, berries, kale, and green tea for isorhamnetin. Fiber can be found in lentils, black beans, oats, chia seeds, apples, raspberries, broccoli, and whole grains. Sunflower seeds, hazelnuts, walnuts, wheat germ, and barley provide beta-tocopherol and beta-tocotrienol. Manganese is present in pineapple, oats, pecans, brown rice, chickpeas, and spinach.
Foods That May Increase Risk
Diets high in added sugars were linked to a higher risk of dementia. Some dairy-derived nutrients, including lactose, were also associated with greater risk. However, the study noted that dairy foods also contain vitamin D2 and calcium, both tied to healthy aging, so the overall effect of dairy on brain health is not straightforward.
The findings underscore that eating a whole-food diet rich in antioxidant fruits, vegetables, nuts, and seeds supports long-term brain health. While the study highlights specific nutrients, it also reinforces the value of an overall balanced eating pattern.
