Fish and cats seem like a natural match. From tuna treats to salmon dinners, fish appears in plenty of cat foods.
But it may not suit every cat. If your cat is often itchy, overgrooms or has an unsettled stomach, you might start wondering whether something in their food is involved.
Fish could be part of the picture, but those signs can have lots of causes. The most helpful first step is to slow down, look for patterns and collect clear information.
What signs might you notice?
Every cat is different, but owners may notice:
- frequent scratching or licking;
- overgrooming or patches of thinning fur;
- recurring trouble around the skin or ears;
- vomiting, soft stools or diarrhoea; or
- changes in appetite or litter-tray habits.
These signs do not prove that fish is responsible. Fleas, environmental triggers, infections and other health problems can look very similar.
If your cat seems unwell, stops eating, loses weight, is repeatedly sick or has sore or broken skin, contact your vet promptly.
Fish can hide in more places than you think
“Fish” is not always listed as one simple ingredient. You may see salmon, tuna, whitefish, fish meal, fish stock or fish flavouring.
It can also appear in treats, supplements and flavoured medicines. Even a food with chicken or another meat on the front of the packet may contain extra animal proteins in the full ingredient list.
Take a quick photo of each label so you have an accurate record. Include:
- everyday food;
- treats and table scraps;
- supplements;
- dental products; and
- flavoured medicines.
That is much easier than trying to remember everything later.
Keep a simple seven-day diary
For one week, write down what your cat eats and when you notice a change.
Record:
- the exact food, flavour and brand;
- any fish ingredients shown on the label;
- treats, supplements and medicines;
- scratching, licking or overgrooming;
- vomiting or stool changes; and
- anything else that changed at home.
Photos can help you compare skin or coat changes over time. If several people feed your cat, keep one shared record so nothing is missed.
Our pet food and symptom diary guide gives you an easy place to start.
Avoid changing everything at once
It is tempting to remove several foods as soon as you suspect a problem. That can make the pattern harder to understand and may leave your cat with an unsuitable diet.
Share your notes with your vet. If they think food may be involved, they can guide you through a suitable diet trial. This usually involves feeding a carefully selected diet and later checking whether the previous food brings the signs back.
Treats, table food, supplements and flavoured medicines matter during this process too, so follow the plan your vet gives you.
Where a Test My Pets report may help
If you would like to explore possible sensitivities, take a look at our Cat Optimum Test and check what is included before choosing.
Your report can be used as a starting point and a guide when reviewing your cat’s routine. It does not diagnose a fish allergy or explain the cause of symptoms, so speak to your vet before making significant or prolonged changes to your cat’s diet.
Atlas, our 24/7 AI assistant, can help with questions about Test My Pets orders and reports. If your question is more complicated, a member of our customer service team will get back to you as soon as they can.