Sensitive teeth after eating specific food?

Occasionally, I notice that my teeth (the molars) have suddenly become very sensitive. It’s a bit like chewing on tinfoil. It lasts for a few days, while slowly disappearing.
Last time this happened, I think it was right after I ate something. Unfortunately, there were several things I had eaten, so I’m not sure which.
Obviously, I should ask my dentist, but as it just went and not seemed urgent, I’ll do that at my checkup. In the meantime, perhaps someone knows about this, and what could be the cause.
(Possibly related is that my teeth never have been the most healthy, and many molars contain fillings. Not sure if it are only the ones with fillings that were sensitive.)