Grain-free became a trend a few years ago, but the science behind it is shakier than the marketing suggests.

• Most dogs digest grains just fine: Corn, wheat, and rice aren't inherently bad for the average dog.
• Grain-free isn't the same as low-carb: Many grain-free foods just swap grains for potatoes or peas.
• FDA has flagged a possible link: Some grain-free diets have been connected to a heart condition called DCM, though research is ongoing.
• True grain allergies are rare: Most food sensitivities in dogs are actually to specific proteins, not grains.

Unless your vet has diagnosed an actual grain allergy, there's no strong reason to default to grain-free.