Are Firehouse Subs Kalamata Olives High in Histamine?

Firehouse Subs Kalamata Olives

High histamine

Kalamata olives are high in histamine because they are brine-cured in vinegar.

Food here is usually assembled to order from components that were prepped earlier in the day, so it tends to be fresher than a drive-through and less fresh than cooking at home. Histamine builds up as protein foods sit, so how long the chicken or beef has been in the warmer matters as much as what is in the bowl. Treat the rating above as a starting point.

These are kalamata olives packed in sea salt, vinegar, and olive oil.

Kalamata olives — olives are cured in brine, and that curing process is what makes them high in histamine.
Vinegar — the vinegar in the pack adds a moderate amount on top of the cured olives.

Skipping the olives is the simplest way to keep your sub lower.

This rating comes from Firehouse Subs' own published ingredient statement, read on August 11, 2026. Restaurant recipes vary by location and change over time, so always check the current listing: source 1, source 2. How we rate foods →

Firehouse Subs Kalamata Olives and Firehouse Subs are trademarks of their respective owners. This page is an independent histamine reference and is not affiliated with, endorsed by, or sponsored by the brand.