Human diabetes is on the increase, and Dr Stijn Niessen, of the Royal Veterinary College (RVC,) says the same trend can be seen in pet cats.
He suggests about one in every 200 pet cats now has type-2 diabetes, compared with some one in 900 just three decades ago.
“Cats are designed to be hunters – but now there are lots sitting in inner-city apartments getting little exercise and being fed frequently, often as a misplaced sign of affection,”
When it comes to dogs, about three in every 1,000 have diabetes in the UK.
Hyperactive, restless cats that are losing weight despite eating ravenously may have hyperthyroidism.
Just like in humans, this condition occurs when the thyroid gland in the neck produces excess hormones.
One way to treat an overactive thyroid is to give the cat an injection of radioactive iodine.
The iodine ends up concentrated in the thyroid gland and emits radiation, killing overactive thyroid cells.
This is a good way to cure hyperthyroidism, but cats have to be kept in isolation for several weeks after as they are likely to be emitting radiation in their litter trays for some time.
Dogs, on the other hand, are more likely to suffer the opposite problem.
About four in every 1,000 pet dogs in the UK are seen by vets for underactive thyroids.