Pet Factsheets

Cats are generally active and able to regulate the amount of food they eat. In the wild, cats spend 6-8 hours daily hunting and are only successful 10-15% of the time they try and catch a bird or mouse. So, lots of running around for a bite to eat! However, there is an increasing trend for modern cats, like modern man, to eat more high fat food and take less exercise than their predecessors. Gourmet cat foods are delicious and "easy to catch", and we like to pamper our pet with what we consider the best. Just as in people there is a risk that your cat may become overweight. Obesity is an excessive accumulation of fat in the body that adversely affects health - it does not just mean being overweight.

Is my cat overweight or obese?

It is often difficult for us to see that our own pet is overweight as weight gain is so gradual. Sometimes you suddenly notice the difference in your cat's appearance when you look back at old photographs. In most cases it will be a friend or your vet who points out the problem.

When you are stroking your cat next, run your hand gently over its backbone and ribs. In an ideal weight cat you should be able to feel the bones without pressing too hard (if you can see the bones then your cat may be too thin). If you cannot feel the backbone easily then your cat is overweight. These cats also tend to have a "baggy tummy" hanging between their back legs. If the weight gain is allowed to continue your cat is at risk of becoming obese and developing obesity-related diseases such as diabetes.

My cat hardly eats anything - how can it be fat?

Many overweight animals do not eat very much. It does not take many calories to keep an animal fat. If your cat is overweight it means that it was eating more than it needed for the amount of exercise it was taking at some time in its life. Often obese cats take very little exercise (except when walking from the sofa to the food bowl or litter tray!!) and so don't use up much energy and require very few calories.

A fat cat looks healthy, cute and cuddly?

Most animals with obesity are not taken to their vet because they are fat. It is usually some other disease caused by obesity that prompts their owner to make an appointment with the vet. Obese cats may be unable to groom properly (because they simply can't reach around their girth) and may develop matted coats or skin problems. Obesity can make it more likely that your cat will suffer from other conditions such as cystitis (waterworks problems), liver problems and diabetes. All obese animals are unfit and the extra weight they are carrying puts an unnecessary strain on their joints and heart. This may make them more likely to have problems with an anaesthetic and make it uncomfortable for them to exercise. They play less and can become bored and sleep more. So, although they may look cute, the health risks and lifestyle changes are far from cute.

How can I help my cat lose weight?

There are only two ways to lose weight:

  • Increase the amount of energy used, ie take more exercise.
  • Reduce the number of calories taken, ie eat less energy-dense food.

It is very difficult to force a cat to exercise. Obese cats are often not very active because it is quite hard work for them to run around. Encouraging your cat to go out regularly (even if the weather is not very pleasant) may help. Try different types of toys such as fishing rods, balls, paper bags, catnip patches, etc. Your cat may not want to play initially, like we might not want to go to the gym! But keep persisting. Use your time, attention and play as a reward for cat interaction rather than food. Change your routine to help them change theirs. Play time should be frequent short snatches of a couple of minutes - mimicking what they do in the wild. Allow your cat to catch the toy so it can finish its prey behaviour and not get frustrated or lose interest. Hiding food around the house for your cat to find can also encourage exercise and hunting, as can puzzle feeders (balls or toys you put part of their dried cat food ration into for them to bat about to try and get the biscuits out). Ensure that any food going into the puzzle feeder is deducted from their next meal. Also, make your home three dimensional for your cat - provide elevated eating and sleeping stations so they have to jump or climb to get what they need.

The other proactive way to help your cat lose weight is to restrict what it eats. This can be difficult in some cats who hunt or visit neighbours to be fed. You may have to keep these cats confined to the house (although this restricts exercise and builds frustration) or attach a message to their collar asking other people not to feed them. Alternatively, discuss with your neighbour about fitting a restricted access cat flap (activated by a microchip, infra red or magnet carried by their cat only).

Your vet practice will help design a weight loss plan for your cat that will make sure they continue to eat the protein and nutrients they require to maintain health and muscle strength, but cut down on the calories from fats and carbohydrate. This may be based on the current diet you feed your cat if they are only mildly overweight, or may be a formulated diet, which healps your cat feel full but restricts calorie intake. You must always measure out the food using kitchen scales to get the right amount. Measuring cups are inaccurate. An easy way to start reducing calories intake in some cats is to cut out milk, tit bits, treats and snacks from the diet and offer clean fresh water instead. Cats will also lose weight more quickly and feel fuller if fed a wet diet rather than a dry diet. If you feel a need to offer your cat a treat, you can take some food from their measured ration or deduct the equivalent amount of treat calories from their main meal. Talk to your vet/weight management nurse about needing to do this and they can suggest alternatives or write it into your diet plan. Weight loss will be slow and gradual - but steady and rewarding. Very fat cats will take over a year to get back to their ideal size. This is normal and not a failure of your part or the cat's. Crash diets in cats are very dangerous as rapid weight loss may cause serious liver disease.

How do I know my cat is losing weight?

Your vet/weight management nurse will weigh your cat for you and calculate how much weight it needs to lose. They will also be able to advise you on diet choice and suggest how much food you should be feeding your cat. Many veterinary practices offer "weight watcher clinics" for pets. You can take your cat along at regular intervals to be weighed and a nurse or vet will be on hand to answer any questions or give advice. Remember, don't be alone. Diets can be tough! If you need support or advice, your vet/weight management nurse will be happy to take time to speak to you. It is sometimes worthwhile having a weekly phone in just to troubleshoot any little problems before they turn into big ones. Also, keep a diet diary where you record food eaten, exercise/play taken and confess any "sins" (eg treats, cat raided the food cupboard, too tired to play with cat tonight, etc). This diary won't be used to judge you but can help determine the reasons why weight loss may not be going to plan.

All practices will have weighing scales so it should be possible for you to arrange a convenient time for you to take your cat along to weigh by yourself. Weigh your cat in its basket but remember to allow for the weight of the basket. Writing the weight on a sticker on the  basket is helpful - although make sure the same blanket/contents are in the cage each time to keep the weight the same.

What if my cat is still not losing weight?

Take your diet diary with your cat to the vet. They may ask you to demonstrate how you measure out the cat's food and question you in more detail about play routines and treats. They may suggest a change of food depending on what the cat is currently eating. If everything seems OK, they will reduce the amount of food you need to feed your cat. Like people, cats are individuals and the amount of food they need may differ slightly from the national average. Conversely, your vet may be concerned your cat is losing weight too fast (which can risk liver disease). If this is the case, they may take a blood test to check for any other diseases or increase the amount of food fed in the ration.

My cat has reached her target weight - what now?

Once your cat has reached her target weight a celebration is called for. This is not the end of the road - rather the beginning of a new life. Just as in people it is common for an obese animal to regain all the weight that has been lost if it returns to its previous diet. Your vet/weight management nurse will advise you on what and how much of a maintenance diet to feed. The diet can be any food you wish, but we need to monitor any change in body weight closely over the first 6 months. You should maintain regular weigh-ins and check ups, preferably at least twice a year. You will need to help maintain your cat's active lifestyle - but often your cat is so happy to regain activity and play, this is not difficult.

Maintaining a normal bodyweight is an important part of keeping your cat healthy. It is not possible to recommend a single diet that will be suitable for all cats. If you are in any doubt about your cat's weight ask your vet or weight management nurse for advice.

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