Alzheimer's disease is a neurodegenerative disorder characterized by accumulation of Aβ peptide aggregates in the brain. Using ThT fluorescence assays, AFM imaging, NMR and CD spectroscopy, and MD modeling we show that lysozyme - a hydrolytic enzyme abundant in human secretions - completely inhibits the aggregation of Aβ peptides at equimolar lysozyme : Aβ peptide ratios.