Scientists have discovered that subtle changes in the blood may reveal the earliest signs of cognitive decline long before symptoms become obvious.

These changes are caused by chemicals produced by gut bacteria—reinforcing the idea that the gut–brain connection plays an important role in early memory changes.

It is hoped that the breakthrough could one-day transform how we detect dementia.

Lead researcher Dr. David Vauzour, from UEA’s Norwich Medical School, said, “Dementia is one of the greatest public health challenges of our time.