Can Dogs Eat Mayonnaise? Fat, Garlic & Pancreatitis

Can Dogs Eat Mayonnaise?

AVOID

AVOID — Mayonnaise is not toxic, but it is very high in fat and may contain onion, garlic or salt. A lick is unlikely to harm; larger amounts can cause stomach upset or pancreatitis.

Mayonnaise is made from oil, egg and vinegar and is very high in fat. Small licks are unlikely to cause harm, but larger amounts can upset the stomach or trigger pancreatitis, and flavoured mayos may contain garlic or onion.

If your dog licked a little mayonnaise, watch for stomach upset. Contact your veterinarian if your dog ate a large amount, has had pancreatitis, or the food was garlic aioli or a salad containing onion. If your dog vomits repeatedly, has a painful belly or is very quiet, contact a veterinarian, or an emergency veterinary clinic out of hours, straight away.

A swirl of mayonnaise on a plate next to a piece of fried potato

Quick answer

Category: Other
Recommended preparation: Not applicable
Main concern: Very high fat (pancreatitis risk); garlic or onion in flavoured varieties
Suitable as everyday food: No — not a good treat

The full answer

Mayonnaise is an emulsion of oil, egg yolk and vinegar or lemon. Its ingredients are not toxic to dogs, and a small lick from a plate is unlikely to cause a problem.

The concern is fat. Mayonnaise is very high in fat and calories, and larger amounts can cause vomiting, diarrhoea or, in some dogs, pancreatitis. Flavoured mayonnaises, such as garlic aioli, contain garlic, which is toxic to dogs. Foods made with mayonnaise, such as potato salad and coleslaw, often contain onion.

There is no nutritional reason to give mayonnaise. If you want to add flavour or moisture to your dog's meal, ask your vet about lower-fat options.

Is Mayonnaise Good for Dogs?

Mayonnaise offers calories from fat but little nutrition.

Potential benefits

None

Risks and Things to Know

Very high in fat
Garlic aioli and flavoured mayos contain garlic
Salads containing mayonnaise often include onion
May cause vomiting, diarrhoea or pancreatitis in larger amounts

How much is okay?

We do not recommend giving mayonnaise. A lick is unlikely to cause harm.

How Should I Prepare It?

Not applicable. Keep jars and salads out of reach.

Can Puppies Eat Mayonnaise?

Puppies are sensitive to fatty foods. Avoid mayonnaise.

What If My Dog Ate Too Much?

A large amount of mayonnaise may cause vomiting, diarrhoea and pancreatitis.

If your dog ate a lot, or garlic aioli or a salad with onion, contact a vet.

This guide is for general educational purposes and isn't a substitute for advice from your veterinarian. If your dog has eaten something potentially toxic or is showing concerning symptoms, contact a veterinarian promptly.

Frequently Asked Questions

A lick is unlikely to harm, but mayonnaise is very high in fat and not a good treat.

Not by itself, but garlic aioli and some salads contain garlic or onion, which are toxic.

Usually not. It often contains mayonnaise, onion and salt.

It may cause vomiting, diarrhoea or pancreatitis. Contact your vet for advice.

How this guide was written

Last updated 13 October 2026. We write from widely published, mainstream pet-health sources and avoid presenting feeding amounts as veterinary prescriptions.