By Molly Knudsen, M.S., RDN | May 05, 2026
A new study published in the journal Nutrients followed more than 6,200 U.S. adults aged 50 and older for seven years to examine how dietary nutrients affect dementia risk. Researchers asked participants how often they ate 163 foods and beverages over the previous year. They then analyzed 101 individual nutrients and created a composite score based on how combinations of these nutrients influenced risk. Each participant underwent a cognitive assessment, and a close contact answered questions about the participant’s memory.
About the study
The study used a food frequency questionnaire to gather dietary data. Researchers looked at each nutrient separately and then combined them into a score to see the overall effect on dementia risk. Cognitive function was measured through direct testing and reports from a family member or friend.
Five protective nutrients identified
The results showed that five nutrients were linked to a lower dementia risk:
- 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. Food sources include red onions, pears, apples with skin, berries, kale, and green tea.
- Dietary fiber – Nearly 95 percent of U.S. adults do not get enough fiber. It feeds gut bacteria and supports cognitive function. Good sources are lentils, black beans, oats, chia seeds, apples, raspberries, broccoli, and whole grains. The article notes that a fiber supplement can help reach daily needs.
- Beta-tocopherol and beta-tocotrienol – Forms of vitamin E known for antioxidant activity and protection against oxidative stress. They are found in sunflower seeds, hazelnuts, walnuts, wheat germ, and barley.
- Manganese – A trace mineral essential for enzyme function and brain energy metabolism. It plays a role in neurotransmitter synthesis and may protect brain cells from oxidative damage. Sources include pineapple, oats, pecans, brown rice, chickpeas, and spinach.
Foods that may increase risk
Diets high in added sugars were linked to a higher dementia risk. Some dairy-derived nutrients, including lactose, were also associated with greater risk. However, the study pointed out that dairy foods are also rich in vitamin D2 and calcium, both tied to healthy aging and longevity. Dairy is a complex food, and the wide range of nutrients can pull its overall impact in both positive and negative directions.
Takeaway for brain health
The study reinforces that eating a diet based on whole foods with antioxidant-rich fruits, vegetables, nuts, and seeds supports long-term brain health. The article also mentions a supplement called brain guard+, described as sharp, clear, focused, and science-backed support for the mind. For those who want a more specific plan, the article suggests a particular diet structure.
Sources: https://www.mdpi.com/2072-6643/17/12/1960 and https://pubmed.ncbi.nlm.nih.gov/21242196/
