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    1. Assess Your Pet's Girth

    "Owners spend so much time with their pets, they often don't recognize that their dogs or cats are overweight," says Kathryn Michel, DVM, an assistant professor of nutrition at the University of Pennsylvania School of Veterinary Medicine. "But they need to determine the optimal body condition for their specific pets." To do so, she recommends doing a rib check on dogs, similar to pinching an inch on our own waistlines: Place your thumbs on your canine's spine and let your fingers hang down. You should be able to easily discern each of your dog's ribs under a thin layer of fat as you glide your fingers along the torso. If you can't find them, it's time to trim down.

    And though some people think a Garfield-size gut on a cat is cute, abdominal fat is actually a sign that your kitty is too heavy. "On a cat, a rib check is deceiving," says Michel. "Instead, look for 'fat pads' underneath the belly. If you can see them, your cat needs to lose weight." Finally, just as humans have waists, so do animals. "Dogs and cats should have indentations on their sides when you look at them from a top view," says Dan Christian, DVM, executive director of the Purina Pet Institute.