Did you know that a dog’s chances of developing certain health conditions may be associated with their size?

The Dog Aging Project has allowed researchers to study the lifetime risk of health issues across 25,000 dogs in the United States. Among the 238 breeds studied, smaller dogs tend to develop diseases affecting the eyes, heart, liver, pancreas and respiratory system.

On the other hand, large dogs are more likely to develop cancer, bone-related issues and gastrointestinal diseases. They’re also at higher risk of neurologic and endocrine conditions as well as ear, nose or throat problems. Diseases of the urinary tract occur regardless of a dog’s size.

Eventually, researchers hope to unravel the “why” behind these links.