Scientists at the University of Wisconsin–Madison in the United States have found that a chemical made by gut bacteria may speed up memory loss in Alzheimer’s disease. The chemical is called imidazole propionate, or ImP. Bacteria in the intestines produce ImP when they break down an amino acid called histidine, which is found in many foods with protein.

Researchers believe ImP might be important because it can leave the gut, enter the blood, and reach the brain. In their study, scientists looked at blood samples from almost 1,200 people and found that people with higher levels of ImP had more signs of Alzheimer’s disease and lost their memory abilities faster.

The main result of this research is that people with high ImP levels may be at greater risk for Alzheimer’s disease. Scientists hope this new information could help create new medicines in the future to lower ImP and slow the disease, but there is no such treatment yet.