Every year, Americans grow fatter and fatter.  

The US Centers for Disease Control and Prevention (CDC) has labeled us "obesogenic," meaning we're "characterized by environments that promote increased food intake, non-healthful foods, and physical inactivity."

We're fat. And we're passing it on... to our pets.

According to the Association for Pet Obesity Prevention, an estimated 51.5% of dogs and cats in the United States are overweight or obese. That's 89 million of our furry friends.

And the health risks for overweight and obese dogs and cats mirror those that can be found in their overweight and obese owners: osteoarthritis, insulin resistance and Type 2 Diabetes, high blood pressure, heart and respiratory disease, cranial cruciate ligament injury (the tearing of important ligaments in the knees), kidney disease, and many forms of cancer.

Feeding our pets the right amounts of their food is key is keeping them trim and healthy.  But many of us probably don't know how much our dog or cat should be eating.

Sure, there are feeding guides on labels of nearly all bags and cans of pet food, but those are generally-recommended amounts. And person with a dog or cat will tell you just how unique his or her animal companion is.

Enter CU-PetHealth, a new app created by the College of Veterinary Medicine at Cornell University.

The app, available for download on iTunes for $3.99, is designed to work on both the iPhone and the iPad.  

"The idea came from a class project about designing a way to manage your pet's health via smartphone technology," said Joe Wakshlag, assistant professor at Cornell's College of Veterinary Medicine.

"iPhone is what everybody was using as far as the students were concerned. They felt they could reach more people through the iPhone and the iPad."

Like other pet health apps, CU-PetHealth allows users to store their pet's medical history and set reminders for upcoming vet appointments.  But CU-PetHealth sets itself apart from the others by showing the user the proper amount of food to feed their dog or cat based on age, weight and other factors.

Keeping our dogs and cats healthy is as simple as feeding them the proper amounts of food, making sure they get enough exercise, and staying on top of their vet visits.  With smartphone apps like CU-PetHealth, it may get even simpler.