Should I switch my dog off grain-free food?

If your dog is thriving on their current food, the DCM headlines on their own aren't a good reason to change it. The investigation that started the worry closed without establishing a link, and switching food carries its own small costs: an unsettled stomach, a fussy week, and the loss of whatever was working.

There are better reasons to switch. If the ingredient list is heavy on pea protein, pea starch and lentils with not much named meat behind them, that's a fair reason to look elsewhere, whether the food is grain-free or not. Same if your dog's coat, energy or stools have been off for a while and nothing else explains it.

When you do change, go slowly. A week to ten days of mixing, starting at about a quarter new food and working up, gives the gut bacteria time to catch up. Rushing it is the most common reason a good food gets blamed for a bad week.

And if your dog has been diagnosed with a heart condition, or is on a therapeutic diet for anything, don't make the call alone. Take the bag, or a photo of the ingredient panel, to your vet and decide together.