People with high levels of sugar in the body have a greater risk of developing Alzheimer’s disease, researchers report.

A team from the University of Bath has discovered a mechanism which links high blood sugar levels and Alzheimer’s. Research has previously shown a significant relationship between Alzheimer’s disease and type 2 diabetes.

The findings provide “yet another reason” for people to control how much sugar they consumen, the researchers said.

Researchers already knew before this study that sugar can damage cell proteins involved in the development of Alzheimer’s, but the specific molecular link between the disease and glucose was not understood, until now.

During this study, the study team examined brain samples from some people with Alzheimer’s and some without.

What they found was that during the early stages of the condition, an enzyme called macrophage migration inhibitory factor (MIF) is damaged by glycation (having too much sugar in the blood).

This affects the enzyme’s main function, to control the body’s immune responses and regulate insulin.

The findings show that the decrease of MIF activity could indicate the “tipping point” for the progression of Alzheimer’s. As the condition advanced, the enzyme glycation increased.

“We’ve shown that this enzyme is already modified by glucose in the brains of individuals at the early stages of Alzheimer’s disease. We are now investigating if we can detect similar changes in blood,” said Professor Jean van den Else, from the University of Bath’s department of biology and biochemistry.”

“Normally MIF would be part of the immune response to the build-up of abnormal proteins in the brain, and we think that because sugar damage reduces some MIF functions and completely inhibits others that this could be a tipping point that allows Alzheimer’s to develop.”

Dr Omar Kassaar, who is also from the University of Bath, added: “Excess sugar is well known to be bad for us when it comes to diabetes and obesity, but this potential link with Alzheimer’s disease is yet another reason that we should be controlling our sugar intake in our diets.”

The study appears online in the journal Scientific Reports.