Sad to see the same advice that has failed to reduce human obesity is being recommended for cats.
What is the main ingredient in most commercial pet foods?
I'm sure there is probably some variation in the different brands but typically I would expect there to be around 30% protein, 10% fat, 12% ash/fibre so that's 52%
#Guess what the remaining 48% will be.
Carbohydrate four and sugar no doubt and probably not whole grain either.
If you look online for BARF Bones And Raw Food or Biologically Appropriate Raw Food you'll see the type of foods cats and dogs evolved to feed on.
Raw Food Diet for Cats: A Natural Solution
Cats are getting obesity and diabetes for exactly the same reasons humans do. To many inflammatory refined carbohydrates, inflammatory sugars and inflammatory omega 6 oils.
If we fed them (or ourselves ate) the foods cats/dogs would have eaten before they became domesticated (or before we became settled farmers instead of hunter gatherers) then they would be less likely to become fat and ill.
Bear in mind the trend is for increased obesity in Laboratory animals as well so don't blame just the pet owner
They mention other factors that may be causing the problem. endocrine disruptors, virus involvement. Similarly the increase in ground level ozone that is lowering human vitamin d status (both urban and intensive agriculture has raised ozone levels) will also reduce pets chances of getting vitamin D. Everything that causes an increase in inflammation and reduces anti inflammation reserves will be adding to the problem.