"Dogs may be 'off their food' and eat less when they are feeling bad, or they might be extra-interested in food," Fratt says. Sometimes, a stressed-out dog might have an achy stomach, or just might not feel like eating. On the flip side, other dogs find comfort in food (just like people) and will eat more when they're stressed, Fratt explains. Either way, try to encourage your dog to eat a normal, healthy amount of food. If the problem persists, see your vet for help.