I believe, and this is a theory, that cat junk food (poor quality dry cat food or perhaps even all dry cat food) confuses the cat into being unable to assess the calorific value per weight of their food which is an innate ability to regulate the amount to eat. Therefore dry food cannot be used for grazing without being regulated by the cat’s owner.
In the UK cat food labelling, as far as I can tell, does not provide us with the amount of calories that a certain weight of food contains. In other words I am looking for the calories per gram information (kcal/g). I understand that in the USA pet food manufacturers must include kcal/g in the labelling.
If the food is high in calories per gram it may be outside the normal range of cat foods which a cat can assess. Obviously the normal cat food for a cat is prey such as mice. I’m going to argue, and I’m open to criticism, that the calories per gram of dry cat food is much higher than that of a mouse. It is higher to the extent that a cat is unable to assess its calorific value properly and ends up eating too much of it.
In human food terms we are talking about the ‘energy density’ of cat food. A mouse is made up of about 72% water. Wet cat food is about 80% water. My argument is that it is not just about the high carbohydate content of dry cat food but its energy density.
You never see obese wild cats unless they are in captivity and overfed by their human caretakers. The argument is that wild cats eat as much as they need and they do this because they have an innate ability to assess the amount of energy in food that they are eating which is their prey. The domestic cat is a domesticated North African wild cat. Therefore the domestic cat depends upon the ability of the African wild cat (subject to 10,000 years of domestication) to assess the energy density of food provided by the human caretaker.
If the food provided is exceptionally energy dense the domestic can can longer assess it properly and ends up eating too much of it, which results in an obesity epidemic. That is the theory. The theory is based on the fact that a lot of cat owners feed their cats dry cat food all the time in an unregulated way and dry cat food has a high energy density. The solution is to feed a certain weight of dry cat food daily if you insist on buying it or better still feed wet cat food. You can work out the daily energy requirements of a cat using a formula but who does it?
P.S. These thoughts may have been discussed on another site but I don’t know of one. Feel free to discuss this topic in the comments section.