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What happens if my 5 kg cat eats one crushed hazelnut daily for a week?

Cats · Food safety

Last reviewed: 2026-09-05 · Reference ranges: ASPCA, Pet Poison Helpline & Merck Veterinary Manual

Short answer

Feeding one crushed hazelnut daily for a week is not toxic, but it's not ideal due to the high fat content. Over time, the extra calories and fat can contribute to weight gain and may upset a cat's sensitive digestive system, potentially leading to intermittent vomiting or diarrhoea. It's better to offer such high-fat treats only very occasionally, and if you notice any digestive upset or changes in appetite, it's wise to stop and consult your vet.

Hazelnuts — Food safety facts

Feed with care · Cats · full breakdown on the linked food page

Not toxic, but very fatty and a choking hazard. One crushed nut at most.

Dogs and cats carry the same rating (Feed with care), so the notes below hold for either pet.

Hazelnuts is not poisonous to cats, but it is easy to over-feed. Rich fat, salt or seasoning can bring on vomiting or diarrhoea within a day, and repeated large portions are a recognised trigger for pancreatitis.

If it ate some before you noticed, watch for vomiting, diarrhoea, loss of appetite, unusual tiredness or a painful, swollen abdomen over the next 24 hours. A one-off small amount in a healthy adult usually passes with water and rest; repeated exposure, a puppy or kitten, a senior, or a pet with an ongoing illness is a reason to call your vet the same day.

Why these cautions matter

Rich, fatty food is the classic trigger for pancreatitis, a painful inflammation of the pancreas that usually needs veterinary treatment rather than rest alone.

The full verdict, portion guidance and serving notes are collected on the Hazelnuts food facts page.

Open the full food page: Hazelnuts food facts →