American Shorthair cats are generally considered to be a healthy breed with a lifespan of 12 to 15 years. However, like all breeds of cats, they can be prone to certain health issues. Some of the most common health issues faced by American Shorthair cats are:

1. Obesity: This breed of cats is known to have a tendency towards obesity and weight gain, which can lead to other health issues such as diabetes, arthritis, and heart problems. Owners should be vigilant about controlling their cat’s diet and providing enough exercise to maintain a healthy weight.
2. Cardiomyopathy: This is a heart condition that can affect American Shorthair cats. Symptoms can include breathing difficulties, coughing, and sudden collapse. Regular check-ups with a veterinarian and monitoring for any signs of cardiac problems can help catch this issue early and provide the best possible outcome for the cat.
3. Hyperthyroidism: This is a common condition in older cats where the thyroid gland produces too much hormone. This can lead to weight loss, increased appetite, and hyperactivity. Treatments for hyperthyroidism include medications, surgery, and radiation therapy.
4. Dental Issues: American Shorthair cats can be prone to dental problems, such as tartar buildup, gum disease, and tooth decay. Regular dental check-ups and cleaning can help prevent these issues.
5. Upper Respiratory Infections: American Shorthair cats can be prone to upper respiratory infections, such as colds and flu-like symptoms. These infections can be caused by bacteria, viruses, or allergens, and can be treated with antibiotics, anti-inflammatory drugs, and other medications.

In conclusion, American Shorthair cats are generally a healthy breed, but they can be prone to certain health issues. Regular check-ups with a veterinarian, a healthy diet, and plenty of exercise can help prevent or manage these issues. By taking good care of their health, American Shorthair cats can live long and happy lives.