What You Eat Could Affect Your Dementia Risk Even If You Already Have Early Warning Signs

A new study published in JAMA Network Open is adding to a growing body of evidence that what you put on your plate can affect how your brain ages, and it turns out diet may lower your dementia risk even after warning signs have already shown up in your blood.

What Did the New Study Find About Brain Health?

The research followed more than 1,800 adults aged 60 and older in Sweden, none of whom had dementia when the study began. Participants completed food questionnaires over six years, and researchers also measured three blood biomarkers linked to Alzheimer's disease and other brain injuries. They then tracked participants for up to 15 years, and 240 went on to receive a dementia diagnosis.

People whose diets scored lower on inflammatory potential were less likely to develop dementia, and that held true even for people who already showed biological warning signs in their blood. Among participants with higher levels of a biomarker called p-tau217, linked to Alzheimer's disease, greater adherence to an anti-inflammatory diet was tied to a 29 percent lower risk of developing dementia. Similar reductions showed up with two other biomarkers tied to nerve cell damage, meaning brain health wasn't a fixed outcome even for people already showing risk.

Which Foods Make Up an Anti-Inflammatory Diet?

There's no single official anti-inflammatory diet, but the term refers to an eating pattern that tends to keep chronic inflammation in check. Vegetables, fruits, whole grains, legumes, nuts, olive oil, and fatty fish like salmon or sardines are generally considered anti-inflammatory, while processed meats, refined carbohydrates, fried foods, sugary drinks, and excess alcohol are associated with higher inflammation.

The Mediterranean diet is one of the best-known examples of this pattern, and it's the dietary approach most consistently linked to better brain and heart health in research. 

How Reliable Is This Mediterranean Diet Research?

This is a well-designed study that followed a large group of people over a long period, which makes it more reliable than shorter research. That said, it was observational, meaning researchers tracked what people ate rather than randomly assigning different diets, so it can't prove that diet alone lowers dementia risk. Participants also self-reported their food intake, which relies on memory and isn't always perfectly accurate, and the study was conducted in older adults in Sweden, so the findings may not translate exactly to every population.

Even with those caveats, researchers and independent experts who reviewed the findings describe them as encouraging. The core message is that a Mediterranean diet style of eating, or something close to it, is a risk factor you can actually do something about. It's not the only one, either. Regular physical activity, managing blood pressure and cholesterol, not smoking, limiting alcohol, getting enough sleep, and staying socially connected have all been linked to better cognitive outcomes, and if poor sleep has been part of your own picture, this reader's story about finally fixing four years of bad sleep is worth a read alongside this.

Got Questions About Dementia Risk and Diet?

Can changing my diet lower my dementia risk if I already have risk factors?

This study suggests yes, at least partly. People with elevated Alzheimer 's-linked biomarkers who ate a more anti-inflammatory diet still saw a meaningfully lower risk of developing dementia, though diet alone isn't a guarantee.

What foods should I eat more of for brain health?

Vegetables, fruits, whole grains, legumes, nuts, olive oil, and fatty fish like salmon or sardines are the foods most consistently linked to lower inflammation and better long-term brain health.

Is the Mediterranean diet the same as an anti-inflammatory diet?

Not exactly, but they overlap heavily. The Mediterranean diet is a specific, well-studied eating pattern that happens to be one of the clearest real-world examples of anti-inflammatory eating in action.

You don't need a dementia diagnosis, or even elevated biomarkers, to benefit from eating in a way that keeps inflammation lower. The same patterns linked to brain protection are also tied to lower risks of heart disease, stroke, and type 2 diabetes, so there's little downside to eating more vegetables, whole grains, and fish, and less ultra-processed food. If you have questions about your own diet and long-term health, a family doctor or nurse practitioner can help. Find one accepting new patients near you at medimap.ca, or browse the Medimap Health Hub for more research-backed explainers like this one.

This article is for general information and is not medical advice, diagnosis, or treatment.