Research Links Early Smell Loss to Alzheimer's Disease

Tue, 14 Apr 2026 14:20:00 +0200

A recent study conducted by DZNE and Ludwig-Maximilians-Universität München suggests that loss of smell may serve as an early indicator of Alzheimer's disease. The research indicates that Alzheimer’s can trigger microglia, the brain's immune cells, to mistakenly attack healthy nerve fibers responsible for the sense of smell. This process begins years before cognitive symptoms appear, potentially allowing for earlier diagnosis and treatment. The locus coeruleus, a region in the brain stem critical for regulating smell, sleep, and blood flow, is one of the first sites affected by Alzheimer’s, causing neurons to display 'eat-me' signals that prompt microglial attacks. The study utilized mouse models, human brain tissue, and PET scans of living patients to understand this mechanism. Experts, including Dr. Dale Bredesen, suggest incorporating smell tests into routine screenings for individuals over 35 with a family history of cognitive decline. While smell tests are not definitive, they may