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Is it OK for cats to eat mayonnaise?

Mayonnaise is a condiment made from egg yolks, oil, and an acid like vinegar or lemon juice. It’s creamy, tangy, and often used in sandwiches and dips. But is mayo safe for cats to eat? Let’s take a look at whether cats can eat mayonnaise and the potential risks.

Can Cats Eat Mayonnaise?

In small amounts, mayonnaise is generally not toxic to cats. However, it’s not necessarily healthy either. Here are some key things to consider:

  • Mayonnaise contains no nutrients essential for cats. It is high in fat and calories but low in protein, vitamins, and minerals.
  • The high fat content can cause stomach upset, diarrhea, or pancreatitis if cats eat too much mayonnaise.
  • Onions and garlic are sometimes added to mayonnaise for flavor. Onions and garlic are toxic to cats and can damage their red blood cells.
  • Commercial mayonnaise has high sodium content which can be problematic for some cats prone to heart disease or high blood pressure.

So in summary, a small lick or taste of mayo is unlikely to harm an otherwise healthy cat. But mayonnaise provides no health benefits and can cause issues if consumed in larger amounts. It’s better to keep mayo away from cats when possible.

Risks of Feeding Cats Mayonnaise

Here are some of the main risks and dangers of allowing cats to eat mayonnaise:

Upset stomach, vomiting, and diarrhea

The high fat content of mayonnaise can overwhelm a cat’s digestive system and cause nausea, vomiting, or diarrhea. This is especially true if a cat eats a large amount of mayonnaise. Too much fat taxes the pancreas and intestines.


Pancreatitis is inflammation of the pancreas, a gland that aids digestion. It’s usually caused by a high-fat diet. If a cat consumes a lot of fatty foods like mayonnaise, they are at risk of developing painful pancreatitis.

Obesity and liver disease

Mayonnaise is very high in fat and calories. If cats regularly eat mayo, it can lead to unhealthy weight gain and even obesity over time. Obesity further strains the liver and can eventually lead to liver disorders like hepatic lipidosis.

Garlic and onion toxicity

Some mayonnaise recipes include garlic or onion for added flavor. But both onions and garlic are toxic for cats. They can damage red blood cells and cause anemia at high enough doses. So mayonnaise containing onions/garlic should always be kept away from cats.

High blood pressure

Too much sodium can contribute to high blood pressure in some cats. Since mayonnaise has a fairly high salt content, cats prone to hypertension should not eat mayo frequently.

Healthier Alternatives to Mayonnaise for Cats

Instead of feeding mayonnaise, choose healthier fat sources to give your cat a flavorful snack or pill pocket:

  • Canned fish – Try tuna, salmon, or sardines packed in water. These provide healthy omega-3s.
  • Broths – Low-sodium chicken, beef, or fish broths are flavorful.
  • Coconut oil – Unrefined coconut oil supports digestion and metabolism.
  • Bone broth – Homemade or commercial bone broths deliver hydration.
  • Pet toppers – Look for low-fat, cat-safe flavor enhancers.

When in doubt, check with your vet on appropriate homemade treats and portions for your cat.

Can Kittens Eat Mayonnaise?

Kittens have even more sensitive digestion than adult cats. For a kitten, the risks of mayonnaise are heightened.

A kitten’s small body size means it takes only a small amount of a fatty food like mayonnaise to cause diarrhea or GI upset. Kittens are also more prone to low blood sugar. Mayonnaise will not stabilize blood sugar the way a high-protein meal would.

Onions and garlic are especially dangerous to kittens. Even a small amount risks toxicity. So mayonnaise is best avoided for kittens under 12 months old.

Check with your veterinarian before introducing any new foods, including mayonnaise, to a kitten. It’s safest to stick to high-quality commercial kitten foods and formulas.

Can Cats Eat Egg Salad?

Egg salad is made from chopped hard-boiled eggs mixed with mayonnaise or salad dressing. It’s commonly used as a sandwich filling.

So can cats eat egg salad?

Plain eggs are healthy for cats and a good source of protein. But the mayonnaise or salad dressing makes egg salad inappropriate to feed cats.

A tiny amount of egg salad probably won’t harm a cat. But it’s not a nutritious meal, and can cause digestive upset if cats eat too much egg salad. It’s safest not to let your cat lick up leftover egg salad.

Can Cats Eat Potato Salad?

Potato salad is made of boiled potatoes tossed with mayonnaise, mustard, eggs, vegetables and seasonings.

So is it safe for cats to eat potato salad?

Plain cooked potatoes are fine for cats in moderation. But potato salad contains too much mayonnaise and seasonings to be a healthy choice.

Onions, chives, garlic, salt and pepper are common potato salad ingredients. All of these can be harmful to cats if consumed. Licking up a small bite of potato salad likely won’t harm your cat. But do not purposely feed cats potato salad, as the risks outweigh any benefits.

What About Vegan Mayonnaise?

Some vegan mayonnaise products replace eggs with plant ingredients like soy or pea protein. Is vegan mayonnaise safer for cats?

Vegan mayonnaise is slightly lower in fat and cholesterol compared to regular mayonnaise. However, it still contains very limited nutrients essential for cats, and carries risks if eaten in large amounts.

Too much fat from plant oils can still irritate a cat’s digestive tract. Added flavors and garlic/onions may still be present in vegan mayo.

Small amounts of vegan mayo are likely safe for most cats, but not ideal nutritionally. It’s best as an occasional treat. Check ingredient labels closely to avoid onion, garlic or other additives known to be unsafe for cats.

Can Cats Eat Mayo With Onions or Garlic?

What if the mayonnaise contains extra ingredients like onions or garlic? Here’s how these ingredients affect cats:


Onions contain compounds called disulfides and thiosulphates. Cats cannot efficiently process these. If cats ingest enough onions, it leads to oxidative damage to their red blood cells and anemia.

Baby food with onion or onion powder and mayonnaise with dehydrated onions should always be kept away from cats.


Garlic contains similar sulfides, though less concentrated. But garlic can still cause Heinz body anemia in cats at high doses. Heinz bodies are damaged red blood cells.

So mayonnaise recipes with added garlic powder or raw garlic should never be fed to cats.

Bottom Line on Cats and Mayonnaise

In summary, here are some guidelines on cats and mayonnaise:

  • Small amounts of mayonnaise will not immediately harm otherwise healthy cats.
  • However, mayonnaise has no health benefits for cats. The high fat content can actually cause digestive upset.
  • Onion, garlic, chives, or onion/garlic powder in mayonnaise make it unsafe for cats.
  • Feed cats mayonnaise sparingly, if at all. Look for healthier fat sources like boneless sardines in water.
  • Avoid feeding kittens and cats with medical issues any mayonnaise.

While an occasional lick of mayo won’t hurt, it’s not a beneficial addition to your cat’s diet. Stick to high-protein, species-appropriate commercial or homemade cat foods instead.

Consult your vet if you have any concerns about your cat’s nutritional needs.

Frequently Asked Questions

Can cats eat Miracle Whip?

Miracle Whip is similar to mayonnaise but also includes added sugar and spices. The high sugar content makes Miracle Whip inappropriate for cats. Stick to plain mayonnaise and even then, only in very small amounts.

Can cats eat mayonnaise during pregnancy or nursing?

Pregnant and nursing cats have increased nutritional needs. Kittens also can have sensitive stomachs. It’s best to avoid any high-fat, low-nutrient foods like mayonnaise for expecting or nursing mother cats.

Can cats eat rye bread with mayonnaise?

Plain rye bread in small amounts is likely safe for cats. However, mayonnaise-topped rye bread offers no real health benefits compared to commercial cat foods. The mayo adds unnecessary fat and sodium.

Can cats eat tuna salad?

Tuna salad combines canned tuna with mayonnaise and vegetables. The tuna itself is healthy for cats, but tuna salad contains too much mayonnaise to be a complete meal. Do not feed cats more than 1-2 bites of tuna salad at most.

Can diabetic cats eat mayonnaise?

Diabetic cats have difficulty regulating blood sugar levels. The fat content and lack of carbs or protein in mayonnaise make it unsuitable for diabetic cats. Best to avoid sneaking diabetic cats any bites of mayonnaise.