Part of the challenge in preventing and treating Alzheimer's disease is understanding what causes it in the first place. While genes often play a critical role, environmental conditions can influence the disease's progress significantly.

A comparison of the eating habits of 108 Australians with Alzheimer's with 330 representatives of a healthy control group just might get us a little closer to identifying lifestyle factors that we can control to reduce our risk of developing the condition.

The analysis, carried out by a team from Bond University and Griffith University in Australia, found an association between Alzheimer's and the daily consumption of meat-based and processed foods, such as burgers and pizzas.

Those with Alzheimer's also tended to eat fewer fruits and vegetables and their red and white wine intake was lower on average. It's more significant evidence in drawing a link between diet and the risk of dementia.

"Alzheimer's development in the brain begins in middle age and its effects can be attributed to an uncontrolled lifestyle from a younger age," says biostatistician Tahera Ahmed from Bond University.

With so many factors to consider – from exercise and sleep patterns, to related illnesses, to genetics – the study isn't comprehensive enough to demonstrate diet choices were directly responsible for increasing Alzheimer's risk. It's also not clear how these eating habits could be tied to Alzheimer's pathology

However, we know how closely diet is linked to health. It's also possible that eating these types of food triggers something else that then increases Alzheimer's risk.

The study is just one piece of a growing pile of evidence that what we eat can play a role in determining how susceptible we are to conditions like Alzheimer's. The diet we've become accustomed to in the Western world has previously been linked to the disease.

What's more, ultra-processed food also seems to have some effect on cognitive decline in some people. These foods tend to be lower in nutrients and fiber, and higher in the stuff that's best consumed in moderation – sugar, fat, and salt.

"Such dietary habits impact brain health and contribute to vascular issues and obesity, highlighting the interconnectedness of these health concerns," says Ahmed.

The work to gain a better understanding of Alzheimer's and improved treatments for the disease continues. In Australia, up to 1 in 10 people aged over 65 are affected by Alzheimer's, the most common type of dementia, with similar patterns in other developed countries such as the US.

If scientists are able to identify factors within our control that can bring dementia risk down, those numbers might start improving.

In any case, it's never too early or too late to start living a healthier lifestyle.

"Raising awareness among the youth about the benefits of consuming leafy greens, organic foods, or home-cooked meals is essential, as opposed to regularly indulging in junk or processed foods," says Ahmed.

The research has been published in the Journal of Alzheimer's Disease.