The pet obesity epidemic in the United States appears to be going from bad to worse.

These days, nearly 19 percent of dogs are obese, up from fewer than 17 percent in 2013. The numbers are even worse for cats, with around 34 percent topping the scales, higher than just over 27 percent in 2013.

The numbers reflect more than overindulging and under-exercising. Other factors can include a pet’s lifestyle, hormone levels, genetics — even digestive tract bacteria.

So, talk to your veterinarian about a dietary plan that takes into account your pet’s breed, stage of life and activity. Working on diets with a board-certified veterinary nutritionist also helps.

Until then, remember that some of the biggest weight-gain offenders are treats, so choose low-calorie snacks. One example for dogs is raw baby carrots.