Diabetes mellitus is a common endocrine disorder in dogs, often categorized into two types: Type 1, where the pancreas does not produce enough insulin, and Type 2, where the body's cells become resistant to insulin. This condition leads to elevated glucose levels in the bloodstream, which can cause a variety of health issues if left unmanaged. Symptoms may include increased thirst, frequent urination, weight loss despite a good appetite, and lethargy. Early diagnosis and management are crucial for maintaining a dog's health and quality of life. In terms of longevity, diabetes mellitus can significantly affect a dog's lifespan and overall vitality. Chronic high blood sugar can lead to complications such as kidney disease, nerve damage, and eye problems, which can further complicate a dog's health. By effectively managing diabetes through diet, exercise, and, in many cases, insulin therapy, dog owners can help mitigate these risks. Additionally, recent advancements in veterinary medicine, including emerging geroscience research, may offer new insights into managing diabetes and improving longevity for affected dogs.