Cat owners have been urged to watch the waistlines of their pets as a rising number of felines are diagnosed with obesity-related diabetes.
The cats were weighed as part of the research
A study by Edinburgh University has shown that one in 230 pet cats in the UK is now diabetic.
Overweight cats are said to be more than three times as likely to suffer from diabetes, which develops when the body has problems making insulin.
Neutered males that do not get adequate exercise are particularly at risk.
Cat lovers have been warned to crack down on treats for their pets if they are to avoid the risk of them developing the potentially fatal condition.
Professor Danielle Gunn-Moore, from Edinburgh University's Royal (Dick) School of Veterinary Studies, said: "This is the first study of its kind to try to quantify diabetes among cats in the UK and the results show extremely worrying levels.
"To reduce your cat's risk of developing this often fatal disease you need to keep them active, and not allow them to gain too much weight."
Insulin is a hormone that helps cells use glucose from starchy and sweet foods for energy.
The condition has topped overactive thyroid disease as the most common hormone problem in cats.
The number of diabetic cats is almost five times higher than a previous study carried out in the US in the 1970s.
Between 85% and 95% of diabetic cats suffer from type II diabetes, which is commonly associated with obesity.
More than two million people in the UK have the condition.
Prof Gunn-Moore said: "The lifestyle of cats, just like their owners, is changing.
"They are tending to eat too much, gain weight, and take less exercise.
"Unfortunately, just like people, cats will overeat if they are offered too much tasty food, particularly if they are bored and have little else to do.
"While cats would naturally exercise outside, many cats are now housebound - perhaps because they live in a flat or because their owners feel that it is too dangerous to let them out - so they have little to do all day but eat, sleep, and gain weight."
The research, published in the Journal of Feline Medicine and Surgery, was based on an analysis of more than 14,000 cats whose owners had taken out private pet insurance.
Burmese cats were found to be three times more likely to develop diabetes than any other pedigree breed.