The unpalatable truth is that if you give your dog processed dog food - dried, tinned or in a pouch - you may be feeding them substances that cause them serious, possibly fatal, harm.

In a Channel 5 documentary this week, I am one of a number of canine nutrition experts who accuse the big dog food manufacturers of knowingly shortening the lives of millions of dogs a year.

The big businesses selling us processed dog food use ingredients unsuitable for human consumption - and unsuitable, in my view, for canine consumption.

They make vast profits from something that would otherwise be thrown away. It is a consumer scandal waiting to happen.