The full answer
Generally, yes — cutting boards are hard to fully clean
Wooden and heavily scratched plastic cutting boards can trap gluten particles in small grooves even after washing, making them a common, easy-to-overlook source of cross-contact.
A simple fix
A dedicated cutting board (often color-coded to keep it clearly separate) is one of the easiest and most effective changes a shared household can make to reduce cross-contact risk.
Important context
Individual symptoms, reactions, medical histories, food products, and local labeling rules can vary. Community experiences are not medical evidence.
For personal medical decisions, diagnosis, testing, or treatment, consult a qualified healthcare professional.