Study says your eyes could reveal early symptoms of dementia, 7 things you need to know

We often hear that the eyes are the windows to the soul. But what if they’re also windows to the brain? A new study from the University of Otago suggests that looking into your eyes might one day help doctors spot signs of dementia long before memory loss begins. The study was co-lead by author and University of Otago psychology researcher Dr Ashleigh Barrett-Young.

Here's what you should know:

• Your retina is connected to your brain: The retina is the light-sensitive layer at the back of your eye. It’s actually part of your central nervous system, meaning it’s directly linked to your brain. That’s why changes in your retina can reflect what’s going on in your brain, including early signs of diseases like Alzheimer’s.

• Small blood vessels in your eye might hold big clues: The study found that the tiny blood vessels in the retina, called retinal microvasculature, can show early signs of damage that may be linked to dementia. Narrow arteries and wider veins were seen more often in people with signs of brain ageing.

• Eye scans could be the future of early dementia detection: As per the study, at present, diagnosing dementia early is hard. Cognitive tests often don’t catch it until symptoms are noticeable, and brain scans like MRIs are expensive. Retinal scans, on the other hand, are quick, non-invasive, and much more accessible.

• Your eye health at 45 may predict brain health later: Researchers used data from people in the long-running Dunedin Study, who were all scanned at age 45. Changes in the eyes at that age were already linked to markers of dementia risk, which is much earlier than symptoms usually appear.

• Wider venules could be a red flag: According to the lead researcher, Dr Barrett-Young, she didn’t expect wider venules (tiny veins in the eye) to be so strongly linked to dementia risk. But they showed up across multiple warning signs, making them a new area to watch closely.

• Do not panic: This doesn’t mean your next eye check-up can predict dementia just yet. “We can’t predict your future looking at an eye scan,” says Dr. Barrett-Young. The findings are promising, but more research is needed before they can be used in real-world diagnosis.

• Healthy eyes mean more than just good vision: Looking after your eye health may one day become part of how we protect our brains, too. Eating well, managing blood pressure, and regular eye check-ups are all part of keeping both your eyes, and your mind, in good shape.