Ingredients Cats Cannot Eat

Nutrition & Diet 📅 August 9, 2026 👁 7607

📝 Summary

New owners often ask what cats can eat. The answer: human food is best avoided, and even some dog-safe foods aren't cat-safe. Here are the absolute no-nos.

1 Overview

Before feeding something, know what’s absolutely forbidden, then check online! Here are common no-nos — new owners read more!

[Raw egg white]

Most cats like semi-cooked even raw yolks — OK, since cat stomach acid is strong, resisting Salmonella better than humans.

But always cook the white — raw white’s avidin binds biotin (a B vitamin), harming the cat.

[Uncooked fish]

Many cats like raw-fish taste, but some fish (esp. freshwater) have thiaminase

If eaten raw, it destroys vitamin B1; cats need B1 highly; deficiency causes fatigue, anorexia, weight loss, nerve issues. Cooking destroys thiaminase!

[Tuna]

Careful! Don’t overfeed tuna — its strong taste is addictive; cats may reject other food, unbalancing diet.

Tuna is high in the food chain, accumulating heavy metals; cat food with tuna has higher mercury. Human oil-packed tuna can cause yellow fat disease (steatitis) from too much unsaturated fat depleting vitamin E.

[Cooked bones]

Unlike dogs, cats less into bones, but some think bones clean teeth. Never give cooked bones (any animal) — they splinter and can pierce/block esophagus or gut. Only raw bones (poultry) properly handled under supervision.

[Onion and other alliums]

Onion aroma tempts humans and has antibacterial use, but for cats/dogs allium causes serious complications — disulfides oxidize red cells; some cats are so sensitive even tiny amounts cause weakness, anemia, pallor, rapid breathing.

[MSG]

Abroad, ‘Chinese restaurant syndrome’ from MSG; some cats are MSG-sensitive, showing signs within 48 hours.

[Cured foods]

Sausage, ham, luncheon meat, etc. — high salt, nitrate, MSG, colors, preservatives; carcinogenic; avoid for cats.

[Chocolate]

Chocolate helps human heart/mood but is deadly to cats — theobromine is toxic; ~45 mg per lb can poison, even kill.

Keep all chocolate hidden; tell family/guests/kids about the danger.

[Coffee or tea]

Some cats love coffee/tea aroma and sneak sips; caffeine and theine are CNS stimulants — toxic to cats!

[Summary]

The most mentioned is vitamin B — very important.

Deficient cats: poor appetite, weakness, rough coat, arched back, emaciation, unsteady gait, then seizures. Caused by single-food diet, gut disease, or high excretion. Supplement B, especially for skin-disease cats!

About calcium deficiency

Cat calcium-deficiency symptoms

Early: unwilling to move/jump; touching hind legs causes moan, bite, avoid people. Untreated: constipation, can’t jump; worse: lumbar sags, semi-crouch walk, bigger belly, more urination but less eating. Severe: spine deforms, hind-limb paralysis, hard belly from constipation, can’t stand.

See how scary severe calcium deficiency is! Prevention beats treatment — no owner wants a once-lively cat reduced to illness!

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