When looking at the impact of diet on our health, much of the focus tends to be on the foods that are protective against heart disease and certain cancers.

Or on foods that cause these dangerous issues.

When talking about the brain, the common message is eat more oily fish – and keep ultra-processed foods, especially packaged cakes, chips, soft drinks and preserved meats to a minimum.

Because these foods age the brain, drag on cognitive performance and memory. They also affect your sleep, a brain-driven process.

It goes further than that. A new study demonstrates the “profound” effect between the foods you eat and brain health.

In short, the research showed that “a healthy, balanced diet was linked to superior brain health, cognitive function and mental wellbeing”. Further, people with a healthier diet actually increased their brain volume.

‘Healthy’ means a diet that mostly includes healthy ingredients – the fruits, leafy greens, nuts, seeds and whole grains. We’ve banged on about these foods when examining the virtues of the Mediterranean and similar diets.

But there’s a second part to consider: Your diet needs to be balanced. This means you need a good variety of foods, made up of different vegetables, different fruits and so forth. Variety means you’re getting a greater variety of nutrients.

It also means minimising foods that are, on balance, bad for you. This includes alcohol – even red wine, which has shown some positive impact on heart health.

The problem is, we can’t get past the fact that it’s a carcinogenic.

 The new study

Researchers at the University of Warwick looked at the diet choices of 181,990 participants from the UK Biobank.

These were analysed against a range of variables, including cognitive function, blood metabolic biomarkers, brain imaging and genetics.

The food preferences of each participant were collected via an online questionnaire, which the team categorised into 10 groups (such as alcohol, fruits and meats).

AI machine learning then organised the mass of data into patterns.

They found that a “balanced diet was associated with better mental health, superior cognitive functions and even higher amounts of grey matter in the brain – linked to intelligence – compared with those with a less varied diet”.

Change takes time

How do we end up with the diet we’ve adopted?

The quality of what you eat, and overall wellbeing, is shaped by how much money you have, how well you are educated, and your lifestyle choices. But the researchers found that genetic predispositions are also implicated.

How to change? Having more resources at your disposal certainly makes a difference.

The diet of many Australians is compromised by the high cost of quality foods. We’re eating less fresh fruit and vegetables, in large part because we can’t afford them.

Leaving that aside, the study found that gradual dietary modifications work best, “particularly for individuals accustomed to highly palatable but nutritionally deficient foods”.

The researchers believe – or hope – that “by slowly reducing sugar and fat intake over time, individuals may find themselves naturally gravitating towards healthier food choices”.

What the researcher says

Lead author Professor Jianfeng Feng said the key was establishing healthy food preferences early in life.

In a prepared statement he said: “Developing a healthy balanced diet from an early age is crucial for healthy growth. To foster the development of a healthy balanced diet, both families and schools should offer a diverse range of nutritious meals and cultivate an environment that supports their physical and mental health.”