Not all cases of seemingly inexplicable weight loss are explained by a disease or a condition. Heinze says one of the most common explanations for weight loss is changing your pet’s food.
“I have had people come to me because their dog is losing weight. They had a complete work-up done and no one could find anything wrong,” she says. “It turns out the dog’s food was changed. The owners were feeding it the same amount every day, but the new food had 20 percent fewer calories.”
Heinze says it’s easy to miss this because foods are marketed in seemingly haphazard ways when it comes to nutrition. “Sometimes, a food that is marketed for overweight pets – it might say ‘healthy weight’ or ‘weight maintenance’ or ‘reduced calorie’ – might have more calories than ‘regular’ food,” she says.
If you plan to change your pet’s food, check the ingredient labels of both brands and make the swap based on calories. Heinze says that if you’re looking for food that’s truly meant to help your dog lose weight, look for the word “light” on the label.