Niki Bezzant: Can you eat yourself happy?

Starting with a good baseline diet is key, which can include a chickpea salad. Photo / Brett Elliott

Editorial

Junk food may shrink your brain", said the headline.

This is possibly all many of us would have read of this story, and we may have filed it into the tell-me-something-I-don't-know basket in our brains. Either that or the too-hard basket.

It's typical to feel overwhelmed and negative about so many health and nutrition headlines, which seem to be constantly telling us about yet another thing scientists have found that's bad for us.

In the case of this headline, that's a shame, because what this research seems to be saying is that it might be possible to eat ourselves happy.

There's been emerging evidence pointing to the role of a poor diet in the development of mental disorders, including depression and dementia, as well as research showing that a healthy diet can reduce the risk of depression and cognitive decline.

Now, researchers at Melbourne's Deakin University have added to that. They measured the brains of 255 people, specifically the hippocampus, part of the brain associated with learning, memory and mood regulation, and also implicated in depression and linked this with the subjects' diets.

They found people who ate more healthy foods - fresh vegetables, salad, fruit and grilled fish, for example - had larger left hippocampi than those who ate more of a "Western" unhealthy diet dominated by roast meat, sausages, hamburgers, steak, chips, crisps and soft drinks.

Atrophy of the left hippocampus has been associated with Alzheimer's disease and cognitive decline, and in people with depression the hippocampus has also been found to be smaller.

They're not suggesting food could cure depression or Alzheimer's - serious diseases that need serious treatments - rather the researchers say this finding highlights the important relationship between the quality of our diet and the likelihood of mental health issues.

It's more scientific backing to the hokey old saying "you are what you eat".

It's not hard to believe. We know we tend to feel better, and think better, when we eat better.

Food is the fuel that runs us, and that includes our brains.

Anyone with kids knows they do better when they have good-quality food inside them, and that the opposite is also true.

Science shows poor nutrition in kids negatively affects their ability to learn.

As nutrition expert David Katz puts it, "Once we acknowledge food as the one and only source of construction material for the bodies of children we love, 'junk food' rather loses its sheen of harmless fun."

Smoked salmon with roasted capsicum and basil is good meal to boost your brain. Photo / Babiche Martens

So what do we need to eat to keep our brains, and ourselves, happy?

Starting with a good baseline diet is key. It's the low-GI carbohydrates from beans, lentils, chickpeas and whole grains; good-quality protein from lean meat, fish and tofu; tons of colourful veges and plenty of water for hydration.

Some essential fatty acids are important, too - the omega-3 and omega-6 fats. They're called essential because our bodies can't make them. They have to come from food.

While our diets are typically high in omega-6 fats (found in a range of seeds, vegetables and vegetable oils) many of us could do with more omega-3 fats.

Long-chain omega-3 fats (such as DHA and EPA) are found mainly in oily fish.

Short-chain omega-3 fat (ALA) is found in plant foods such as flaxseeds, chia seeds and walnuts.

You can get omega-3 from supplements of course, but my favourite source is food, specifically fish.

Research has shown a link between eating fish and improvements in mood, and some studies point to an association between fish consumption and a reduced risk of cognitive impairment in middle age.

A plate of grilled salmon, kumara and broccoli is a truly delicious way to boost your brain.

Niki Bezzant is editor-in-chief of Healthy Food Guide magazine.