Top tips for weight management in cats

01 March 2014, at 12:00am

Jayne Laycock reports on her ‘pick of the month’ CPD webinar presented by Dr Alex German, Royal Canin senior lecturer in small animal medicine at the Small Animal Teaching Hospital in Liverpool

MANAGING weight in any species can be difficult especially following the indulgent festive period. However, the independent spirit of our feline friends and their ability to catch their own food makes this species particularly challenging when it comes to implementing a successful weight loss programme.

The Webinar Vet organised for Dr Alex German from Liverpool University to lead a webinar covering the topic of weight management in cats which appropriately took place in the dieting month of the year, January.

Alex explained that one of the most important factors in getting a cat to lose weight successfully is ensuring the owners are fully committed to implementing a weight loss programme.

Firstly, owners have to be convinced there is a problem and he stated that many vets can feel awkward about discussing a cat’s weight issue if the owner is clearly obese. Many vets are concerned that they will offend the owner by discussing the subject.

Alex reassured the audience that in his experience, he has yet to offend an overweight or obese owner by discussing their cat’s weight. It appears that most owners see their cat’s health as very separate from their own and will not link the two together. His advice is to be bold and discuss the problem. After all, most of us wouldn’t think twice about discussing alopecia in a pet if the owner was bald.

Alex also advises that worrying owners by telling them how sick their pet will get if they remain overweight is unlikely to be successful. This has been shown in smokers who are fully aware of the health risks but as they are not immediately sick, tend to go into denial and continue to smoke.

A more effective approach would be to focus on the positive and discuss how much more active and how much happier their cat would be if it lost weight. It may also be really useful to use other owners who have managed to successfully reduce their cat’s weight to act as advocates.

Ideal v. target weight

When deciding on an end weight for a cat, some may aim for an ideal weight whereas others may aim for a target weight. Alex said these two end points were very different and had to be explained. 

An ideal weight is the weight a cat should be when carrying its optimum fat mass, and can be calculated by using the cat’s current weight and its condition score according to the 9 point system. Each point over and above condition score 5 correlates to being 10% overweight.

For example, if a 5kg cat has a condition score of 9, this cat will be 40% overweight, and its ideal weight should be 3kg.

Another more accurate way of ascertaining a cat’s ideal weight is basing it on an ideal historical weight for that individual animal. For example, the weight of the cat at 12-18 months old with a good condition score (of around 4-5) will be that individual cat’s ideal weight.

In most cases Alex advises aiming for an ideal weight when an overweight cat is still young and has many more years to live.

The target weight in a cat is not necessarily its ideal weight but is usually a weight which would be considered appropriate to improve that cat’s quality of life; e.g. a target weight could be used in older cats where weight loss to a certain level could help to manage a condition such as osteoarthritis or type 2 diabetes.

Getting cats to lose weight

Humans and cats have some similarities when it comes to losing weight. Alex explained that in both cats and humans, although exercise can significantly contribute to weight loss, it is far more efficient to reduce calorific intake.

It would take an hour’s worth of walking to burn the 260 calories consumed after ingesting a Mars bar. This seems a considerable amount of effort for just a moment of satisfaction. This is also the case for cats: if an owner decides to give a cat a “little treat” such as a tin of tuna, this would be the equivalent of us eating seven tins of tuna. Ultimately, the best way of getting a cat to lose weight is by calorie restriction.

Alex also stated that weight loss and weight gain is purely down to the calories consumed and nothing to do with the type of food eaten. This was demonstrated by an overweight professor who decided to put himself on a confectionary only diet but restricted the calories to a level that would cause weight loss.

The professor lost weight in exactly the same way as someone going on a “healthier” diet. Despite this, Alex strongly recommends putting cats on specific weight-loss diets as consuming the right types of food can reduce appetite and increase the likelihood of successful weight loss.

Once the target or ideal weight has been calculated for that individual cat, Alex explained that these diets have to be weighed accurately. He recommends always weighing specific amounts of food for an individual cat on the practice scales and then getting the owner to re-weigh the food at home on his or her own scales so a consistent and appropriate amount is always fed.

He stressed that we should never rely on measuring cups as they are often inaccurate, having a variability of up to 20% between the size of portions.

Another hurdle often faced by owners when trying to implement a weight loss diet in cats is the presence of a slim cat and an overweight cat in the same household. Alex advised that a simple cardboard box could help to solve this problem.

The slim cat’s food can be placed in the box with a hole cut into it which is only big enough for the slim cat to get through. The overweight cat has no access to the slim cat’s food and can only access its food outside of the box, allowing the slim cat to feed ad lib. A more extreme version of this would be to use microchip cat flaps in each cat’s individual room, allowing access only to its own food.

There are two “types” of feeders in the cat world, which is remarkably similar to humans, he said. There are the ad-libers who tend to over eat, and the regulators who self- regulate and manage their food intake at appropriate levels.

The type of feeder an individual cat is can sometimes be predicted as the ad-libers tend to gain weight rapidly in their youth making them much more likely to be obese as adults. It is important to try and recognise these susceptible cats when they are in for their health checks so their weight can be managed appropriately.


Calorie restriction is the most efficient way of causing weight loss in cats but Alex was keen to stress that exercise can also be useful as it encourages owner involvement. The more the owners are involved, the more likely they will be on-board with implementing a successful weight loss programme.

Alex said that cats can be encouraged to exercise by providing them with a three-dimensional activity centre, but better still to get owners to play with their cats by exploiting their natural behaviour. He advised making short unpredictable movements with a small toy which imitates prey when being hunted.

It is also important to allow a cat to catch this toy intermittently, preventing frustration. Laser pens can also be useful in encouraging play in cats but as there is never an opportunity to catch a laser, they are not ideal.

Making cats work for their food can also be helpful and Alex advised putting kibbles in empty plastic drink cups or toilet rolls which are stuck together, helping to slow food intake whilst offering exercise.


We all know that successfully implementing a weight loss programme in cats can be difficult and this webinar provided practical and realistic advice.

Dr German has also provided further webinars discussing the broader issues surrounding obesity, including its causes and consequences, with current thinking centring around fat acting as a single inflammatory organ.

This is fascinating stuff, if not a little scary, and it really is well worth taking the time to listen and learn more about the subject.

Listening to these webinars will not only help you manage weight loss in cats, but will also help to boost all of those (including myself) whose new year’s resolution was to eat healthily and exercise more.