By Dr. Chinta Sidharthan Reviewed by Susha Cheriyedath, M.Sc. May 15 2025 Could a common stomach bug help shield the brain from Parkinson’s? New research links H. pylori infection to reduced disease risk, opening fresh avenues in neurodegenerative science. Study: Helicobacter pylori infection might be a protective factor against Parkinson’s disease . Image Credit: Liya Graphics / Shutterstock Around half the world has Helicobacter pylori infections,  which are typically linked to ulcers.