With caution — cats and olives
Plain, pitted olives are not toxic to cats in small amounts. A notable percentage of cats have a behavioural response to olives — rolling, licking, and rubbing — that appears to be related to isoprenoid compounds in olives that share structural similarity with nepetalactone (the catnip compound). The primary safety concern with olives is sodium: commercial olives are preserved in brine and can contain 600–1500mg sodium per 100g. Stuffed, marinated, or seasoned olives add further concerns. A plain, rinsed, pitted olive as an occasional treat is low risk; a cat eating from the jar is not.
🏆 Pet Care Community Safety Score™ — Olives for Cats
"Olives are interesting because of the catnip-connection behaviour. Some cats — the same cats that respond to catnip — roll around in olive brine spills or get quite focused on an olive you're eating. The isoprenoid compounds in olives are the proposed mechanism. Safe in one or two, but the brine sodium content means I don't recommend olives from a jar as a snack. Rinse the olive first, remove the pit, and offer one piece occasionally — that's the version I'm comfortable with."
The straight answer
Plain, pitted olives rinsed of brine are not toxic to cats. The salt content in commercial olives is the main concern for regular consumption; a single rinsed olive occasionally is a non-issue. The interesting aspect of olives for cats is the catnip-like response that a subset of cats shows — a genuine neurological response to isoprenoid compounds in the olive.
The catnip connection
Catnip's effect on cats is mediated by nepetalactone — a bicyclic monoterpenoid compound produced by Nepeta cataria. Research by Haller et al. and others has identified that the same cats who respond to catnip (roughly 50–70% of the domestic cat population) often show similar responses to:
- Silver vine (Actinidia polygama) — which contains neomatatabiether and actinidine
- Tartarian honeysuckle wood
- Olives — which contain isoprenoid compounds including squalene and related terpenoids
These compounds appear to activate the same olfactory receptor system as nepetalactone. Cats that roll around olive brine, rub their cheeks on olives, or become focused on olive oil are exhibiting the same response they show to catnip — not a toxicity reaction, not a strange behaviour, but a normal neuroactive response shared by the same cat population.
Cats that don't respond to catnip typically don't respond to olives either. The response is genetic.
The sodium problem with commercial olives
Olives as sold in Australian supermarkets and delicatessens are almost universally preserved in brine — a salt solution. The sodium content of commercially brined olives ranges from approximately 600mg to 1500mg per 100g depending on the variety and preparation.
A cat's daily sodium requirement is approximately 42mg. One medium olive (~10g) from a standard brine jar contains approximately 60–150mg sodium — well above a cat's daily requirement in a single olive.
Occasional exposure to one rinsed olive is low risk because: 1. Rinsing removes a significant amount of surface brine 2. The pit and flesh contain much less sodium than the brine itself 3. One olive is not enough to cause acute sodium toxicity in a healthy cat
The risk escalates if a cat accesses a jar of olives and eats multiple, or if the cat drinks the brine liquid. Olive brine as a liquid is extremely high in sodium and is not safe for cats.
Stuffed and marinated olives — specific concerns
| Olive type | Safe for cats? | Concern |
|---|---|---|
| Plain green or black olives (brine-cured, pitted) | Low risk (rinsed, one piece) | Sodium — rinse first |
| Garlic-stuffed olives | No | Garlic is directly toxic |
| Anchovy-stuffed olives | Check | Anchovies in oil/salt — extra sodium |
| Cheese-stuffed olives | Not recommended | Fat and salt |
| Pimento-stuffed olives | Low risk | Capsicum — minimal concern |
| Olives marinated in garlic oil | No | Garlic infused into olive and oil |
| Tapenade | No | Typically contains garlic |
| Olive oil (plain) | Low risk | Very small amounts; high fat otherwise |
Garlic-stuffed and garlic-marinated olives are a consistent concern — garlic is a core allium toxin for cats, and olives marinated in garlic-herb oil have infused the garlic compounds into the flesh of the olive itself.
🚨 My Cat Ate Olives — What Now?
Plain olives are not a toxicity emergency. If your cat ate garlic-stuffed olives or olives marinated in garlic oil, call the Animal Poisons Helpline on 1300 869 738. Sodium overload from several brined olives: monitor for excessive thirst and vomiting.
Signs that warrant a vet call:
- Sodium overload symptoms (excessive thirst
- vomiting
- lethargy) if the cat ate several olives from brine. Pit-related choking risk. With garlic-stuffed or garlic-marinated olives: allium toxicity risk
If your cat ate a large amount or is showing the signs above: Don't wait — call immediately.
📞 Animal Poisons Helpline: 1300 869 738Available 24/7 across Australia. Have your cat's weight, breed and approximate quantity consumed ready when you call.
Frequently Asked Questions
Black and green olives are the same fruit at different ripeness stages. Green olives are unripe; black olives are fully ripe. The nutritional and sodium profiles are similar; the main difference is flavour intensity. Both should be rinsed and pitted before offering.
For more on human foods and cats, see our cat food safety hub and our sesame seeds guide.
📚 Sources & Further Reading
- Haller RL, et al. Behavioural responses of cats to silver vine and other plants related to catnip. BMC Veterinary Research 2021.
- ASPCA Animal Poison Control — Non-Toxic Foods. https://www.aspca.org
- Cornell Feline Health Center — Feline Behaviour. https://www.vet.cornell.edu
- Australian Veterinary Association — Salt Toxicity in Cats. https://www.ava.com.au
