We all know that junk food really isn’t good for us – but it tastes so darn great!

However, thanks to a range of factors including increased intake of saturated fats and refined sugars, and declining inactivity, obesity rates are increasing worldwide, with one in eight people across the globe obese according to the World Health Organization, with the figure rapidly increasing for children and adults alike.

Things are even worse in the US, where one in three adults and one in five children are obese, meaning that they’re at an increased risk of all the health and wellbeing complications that the extra weight and nutritional deficiencies cause.

And even more alarmingly, according to a new study from the University of Sydney in Australia, high intake of saturated fats and refined sugars can lead to lower cognitive function too.

The research, which was recently published in the International Journal of Obesity, studied 55 university students, aged between 18 and 38.

In the study, they were required to complete a virtual reality maze, in which they had to locate a treasure chest. In fact, they had to complete the same maze six times, with memory of the route they took and the landmarks they saw vital to help them keep locating the treasure chest in the allotted four minutes.

In a seventh and final maze, the treasure chest was removed, but the maze remained the same, with participants asked to locate the area in which it had once been.

Then, their results were compared to questionnaires that they had previously completed about their diet – in particular the amount of fat and sugar that they regularly consumed – as well as their BMI.

And the results were astonishing, with those who consumed less fat and sugar finding it much easier to complete the mazes successfully – something that is clearly linked to the effects of refined sugar and saturated fat on the brain, and particularly spatial navigation and memory.

As Sydney’s Dr Dominic Tran explained in a statement, this study exemplifies the clear effect that diet has on cognitive function:

“After controlling for working memory and BMI, measured separately to the experiment, participants’ sugar and fat intake was a reliable predictor of performance in that final, seventh, test. We’ve long known eating too much refined sugar and saturated fat brings the risk of obesity, metabolic and cardiovascular disease, and certain cancers. We also know these unhealthy eating habits hasten the onset of age-related cognitive decline in middle age and older adults. This research gives us evidence that diet is important for brain health in early adulthood, a period when cognitive function is usually intact.”

Alarmed by this? Well, luckily the brain is quite forgiving, and if you improve your diet, your cognitive function is likely to bounce back too, as Dr Tran continued:

“The good news is we think this is an easily reversible situation. Dietary changes can improve the health of the hippocampus, and therefore our ability to navigate our environment, such as when we’re exploring a new city or learning a new route home.”

This all leads to one, clear conclusion: eat your greens – your brain will thank you.

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