There's long been evidence that what we eat can affect our risk of dementia, Alzheimer's disease and cognitive decline as we age. But can any one diet actually keep the brain strong and lower dementia risk? Evidence suggests the so-called "Mind diet" might.

The Mind diet (which stands for the Mediterranean-Dash intervention for neurocognitive delay) combines the well-established Mediterranean diet with the "Dash" diet (dietary approaches to stop hypertension). However, it also includes some specific dietary modifications based on their benefits to cognitive health.

Both the Mediterranean diet and Dash diet are based on traditional eating patterns from countries which border the Mediterranean sea.

Both emphasise eating plenty of plant-based foods (such as fruits, vegetables, nuts and seeds), low-fat dairy products (such as milk and yoghurts) and lean proteins including fish and chicken. Both diets include very little red and processed meats. The Dash diet, however, places greater emphasis on consuming low-sodium foods, less added sugar and fewer saturated and trans-fats to reduce blood pressure.

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Both diets are well-researched and shown to be effective in preventing lifestyle-related diseases - including cardiovascular disease and hypertension. They're also shown to help protect the brain's neurons from damage and benefit cognitive health.

The Mind diet follows many of the core tenets of both diets but places greater emphasis on consuming more foods that contain nutrients which promote brain health and prevent cognitive decline, including:

Numerous studies have been conducted on the Mind diet, and the evidence for this dietary approach's brain health benefit is pretty convincing.

For instance, one study asked 906 older adults about their usual diet - giving them a "Mind score" based on the number of foods and nutrients they regularly consumed that are linked with lower dementia risk. The researchers found a link between people who had a higher Mind diet score and slower cognitive decline when followed up almost five years later.

Another study of 581 participants found that people who had closely followed either the Mind diet or the Mediterranean diet for at least a decade had fewer signs of amyloid plaques in their brain when examined post-mortem. Amyloid plaques are a key hallmark of Alzheimer's disease. Higher intake of leafy greens appeared to the most important dietary component.

A systematic review of 13 studies on the Mind diet has also found a positive association between adherence to the Mind diet and cognitive performance and function in older people. One paper included in the review even demonstrated a 53% reduction in Alzheimer's disease risk in those that adhered to the diet.

It's important to note that most of this research is based on observational studies and food frequency questionnaires, which have their limitations in research due to reliabiltiy and participant bias. Only one randomised control trial was included in the review. It found that women who were randomly assigned to follow the Mind diet over a control diet for a short period of time showed a slight improvement in memory and attention.

Research in this field is ongoing, so hopefully we'll soon have a better understanding of the diet's benefits - and know exactly why it's so beneficial.

UK public health guidance recommends people follow a balanced diet to maintain good overall health. But the Mind diet offers a more targeted approach for those hoping to look after their cognitive health.

While public health guidance encourages people to eat at least five portions of fruit and vegetables daily, the Mind diet would recommend choosing leafy green vegetables (such as spinach and kale) and berries for their cognitive benefits.

Similarly, while UK guidance says to choose unsaturated fats over saturated ones, the Mind diet explicitly recommends that these fats come from olive oil. This is due to the potential neuroprotective effects of the fats found in olive oil.

If you want to protect your cognitive function as you age, here are some other small, simple swaps you can make each day to more closely follow the Mind diet:

These small changes can have a meaningful impact on your overall health - including your brain's health. With growing evidence linking diet to cognitive function, even little changes to your eating habits may help protect your mind as you age.