About two-thirds of Americans are overweight or obese, a trend that sadly hasn't missed their pets: More than half of U.S. pets are above their ideal body weight, some alarmingly so.

While fat cats and pudgy pooches are funny in cartoons, in real life they're tubby time bombs ticking away their health with conditions such as diabetes, high blood pressure, respiratory problems, skin issues, joint destruction and pain, even an increased risk of cancer. Remember: We feed them, and we are responsible for this weight gain. Pets? Well, there's no bikini season for pets, no stick-thin pet models on Animal Planet, no trying to squeeze into last year's pair of pants. They'll happily dig their own grave with their food bowl, one bite at a time.

Studies have shown that about 80 percent of pet owners with overweight or obese pets rank them as having an ideal body weight. Doesn't seem to matter that pet owners can't easily feel their pet's ribs, can't see a tucked abdomen (like a wasp) or a defined waist when viewed from above (like an hourglass shape) — they naively think their pets are looking and doing just fine. I've been married 33 years to the love of my life, a fitness zealot named Teresa, and one of things she has taught me (she's a Weight Watchers leader) is that scales don't lie. You can lie to yourself that your pants really aren't that tight or have shrunk, that black clothes still makes you look skinny or that it's the cameras adding the pounds. No matter: Scales are a fitness lie-detector, and regular, frequent weigh-ins can keep you accountable and able to catch problems early on. Teresa and I personally weigh every Tuesday morning and she tracks the results in her planner.

Dog trainer Mikkel Becker and her dog Willy

The same reasoning should apply to pets. Some people think a pet always puts on a few extra pounds during the winter (not as active) or might be putting on just a little weight with those new snacks they really love, but really maybe it's just a lot of hair. We veterinarians hear this one all the time: A lot of hair is to pets as big-boned is to people!

That's why at Almost Heaven Ranch we weigh our dogs every month and track the results. We do this for daughter Mikkel's two Pugs as well. Our pets never, and I do mean never, fluctuate more than 10 percent from their ideal body weight. That means the three dogs that should weigh around 16 pounds (Quixote, Quora, Willy) never weigh more than around 17.5 pounds. If they get into the 17-pound range we decrease treats, increase exercise or both. My Labrador-Pit Bull mix, Gracie, stays at 44 pounds, never above 50. The four barn cats are all at their ideal body weight, and they range from seven to 10 pounds. We use a scale we bought at Staples to weigh packages to weigh the smaller pets, and bathroom scales (weighed with us on alone, then with pets) for the larger dogs.

Obesity is defined as being more than 20 percent above the ideal body weight (about what a pet weighed at a year of age as a young adult). While a Pug that weighs only four pounds extra might not seem like much — let's say Mikkel's black Pug, Willy, weighed 20 pounds rather than 16 pounds — that's like a 150-pound woman now weighing 187.5 pounds. And an eight-pound cat who now weighs 10 pounds … well, that calculates the same way. The extra weight damages the body, and you have to think of every extra piece of kibble, each snack or mouthful being like a hand grenade going off inside.

Besides looking for weight gain, we are always looking for weight loss, especially with our cats. I can't tell you how many times as a veterinarian people have brought a cat in for a medical condition or check-up, not realizing that the animal has turned into a fur-covered skeleton, having lost up to 40 percent of her body weight in a year. Conditions that cause weight loss in pets includes diabetes, hyperthyroidism, Addison's Disease, parasitism, colitis and on and on.

While I always recommend twice-yearly wellness visits for pets (where the veterinary team will weigh your pet and look past any obvious problems to potential problems), by weighing pets at home and tracking the results, you can keep a handle on your pet's weight — and catch problems very early on before they cause any unnecessary pain, expense or worse.