There could be a number of reasons your dog is still overweight, including heredity, temperament, and overall activity level. However, a disease may be causing your dog to become overweight or obese. Hormonal diseases such as hypothyroidism and Cushing’s syndrome commonly cause weight gain. Hormone pills or tablets with cortisone-like drugs could also be contributing to the obesity.
Hypothyroidism is deficient thyroid hormone, and it causes alterations in cellular metabolism that affect the entire body. The dog may not feel like exercising and may gain weight because calories consumed are not matching calories expended. The weight gain then makes the dog feel like exercising even less. Hypothyroidism is usually inherited and a common genetic illness in dogs. Untreated hypothyroidism means a lower quality of life for your dog, but with the proper thyroid supplementation, this condition can be easily controlled, allowing your dog to enjoy a good quality of life.
Cushing’s syndrome (hyperadrenocorticism) is chronic excess of a glucocorticoid hormone, cortisol. This hormone is essential for functions such as maintaining blood glucose levels, metabolizing fats, keeping major organs functioning properly. There are different types of Cushing’s with many symptoms and causes, so it can sometimes be difficult to diagnose. Furthermore, its onset is slow, so its symptoms are often mistaken for signs of age. Cushing’s syndrome can cause reduced activity, change in appetite, and hair loss. Other symptoms include an increased thirst and urination, muscle weakness, and obesity. The cause of the Cushing’s syndrome determines the treatment, which is also influenced by the overall health of the dog.
Adequate exercise and proper diet are essential for all animals, but if your dog is overweight and you suspect an underlying disease, see a veterinarian for a thorough physical exam including laboratory tests.