The full answer
Yes — this is a very common, easy-to-miss source
When a knife used on regular bread goes back into a shared butter, jam, or peanut butter jar, it leaves crumbs behind — anyone who uses that jar afterward, including someone with celiac disease, can then pick up gluten from it.
A simple household fix
Using squeeze bottles, separate labeled jars, or always using a clean utensil avoids this entirely — it’s a small habit change that closes off one of the most common cross-contact sources at home.
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.