They're packed with vitamins and antioxidants that can help support your dog's immune system as the weather changes." “Pumpkin is rich in fibre and helps with both diarrhoea and constipation, keeping your dog's digestive system balanced,” he says. However, while these hacks can help, Simon emphasises that the most impactful thing you can do for your dog's health is to ensure their food is right. He says: "Many common health issues in dogs, like itchy skin and digestive problems, are often linked back to a poor-quality diet full of grains and fillers. These ingredients can cause a dog's immune system to be on high alert, making them more susceptible to seasonal allergens and illnesses.