My dog, Molly, has been to the vet a few times in the past couple of months for an infection and teeth cleaning. The vet recommended that Molly lose some weight and asked how much Molly was eating. "One and a half cups a day of ... dog food and some cabbage," I said. And yes, that's using a measuring cup, I explained, not a slurpee cup. Yes, Molly gets exercise--she runs on the treadmill every day. Nonetheless, the vet suggested giving Molly less food.
Is this a good idea? Let's consider some observations, facts and assumptions.
First, is Molly fat? Someone at the dog park nicknamed her "Marshmallow," and her hips look quite a bit wider than her chest when she sits down. Yet there aren't rolls of fat on her. When I pinch her fat around her middle, it's only 3/8" thick. Her hind quarters are too firm to pinch. Her midriff is thick and her hips are wide--but maybe that just means she isn't built like a greyhound. She also has a long, fluffy double coat, which makes her look bigger than she is.
What about weight? She's put on ten pounds since I adopted her in 2007. Molly was pregnant and stray when she was picked up and taken to the animal shelter. The first time I saw her, she had a thin, poor, oily coat, and she was docile and full of woeful charm. In other words, she looked like a stray dog at 45 pounds.
At 55 pounds, she's happy, playful, and energetic. (To be fair, improved diet, exercise and a loving home surely made some of the difference here.) Every day when I come home, she demands some affection for a few minutes and then jumps on the treadmill. I crank it up to 10 miles an hour for a few minutes while she barks at birds and squirrels outside the window. Molly can also run up steep hills like a mountain goat, keep up with any dog at the park, and she'll take on all comers--even pit bulls--if she's attacked. She can run under a bench and out the other side at a full gallop. So even if Molly is fat, she's fit and and athletic.
But so far, it doesn't look to me like Molly is fat. Nevertheless, I tried something that Dr. Williams Davis blogged about recently: checking blood sugar levels to avoid eating things that spike your blood sugar, which will put on weight. Molly's fasting blood sugar yesterday was 49--yes, forty-nine. It seemed low, so I checked my own blood sugar: it was 79. An hour after dinner, her blood sugar was 33. So Molly's dog food (Taste of the Wild, bison flavor) can't make her fat--just full. Two hours after her dinner, my mother's meter showed Molly's blood sugar was back to 49. (I used my own meter for Molly's first two tests.) Despite the low BG readings, Molly doesn't have any signs of hypoglycemia. I think those "normal" BG readings of 75 to 120 for dogs are due to a diet of typical corn-based (read: high-carb, high sugar) dog foods.
Another fact: Molly had a mild heart murmur when I first adopted her. A scan showed two congenital heart defects. Yet the murmur disappeared a few years ago. If a dog with a defective heart is overweight, does she run up mountainsides, chase dogs at the park, and jump on the treadmill at will?
Molly doesn't need to go on a diet: she's not fat, and typical calorie-restricted diets don't work anyway. She's a bit like Joe Nameth: she's fit, she's stocky, and she wears a thick fur coat.