According to the Association for Pet Obesity Prevention, average house cats should generally weigh between 10 and 12 pounds.

However, in the spring of 2012, it was his weight that propelled a two-year-old 39-pound orange tabby named Meow into brief internet fame. His caretakers, staff veterinarians at a Santa Fe animal shelter, took to Facebook and shared posts in which they explained their attempts to save the cat’s life by helping him lose weight.

Before he succumbed to a fatal respiratory illness a few weeks later—a complication from his obesity—Meow earned legions of fans through Facebook and even appeared with his veterinarian/caretaker on Anderson Cooper’s morning talk show. As Cooper struggled to hold Meow, his cohost Kristen Johnson asked, “But seriously, what’s so wrong with a fat cat?”

Sadly, though Meow’s body mass index was exceptional, and rare (possibly record-setting), obesity is the most common health threat faced by pets. Even mildly overweight cats and dogs are at risk for complications that will shorten their lifespans. A recent study showed that Labradors with just 10-20 percent extra body fat lived a median 1.8 fewer years.

Since 2005, the Association for Pet Obesity Prevention (APOP) has documented rising rates of overweight and obese pet dogs and cats in the United States. This tracks with a steady increase, globally, in the number of obese pets, more than half of whom will battle conditions ranging from osteo-arthritis and heart conditions to respiratory problems and liver disease because of their excess body weight.

Research with animals has yielded new insights into how best to prevent obesity in cats and dogs, as well as how to help pets lose the extra pounds. (Hint: New Year’s weight resolutions are a great idea for companion animals, too.)

  1. Weight loss is a challenge for pets just as it is for humans.

The largest international weight-loss study involving obese dogs was published In September 2017. Following a three-month period in which researchers fed the research subjects only diet dog foods, 37 percent did not lose a significant amount of weight. These findings echo the results of an earlier study that tested the efficacy of four popular diets in humans: study participants had only modest success in losing weight after one year. As in these cases, animal research has led to important findings about the role of diet in maintaining a healthy weight for both people and pets.

  1. People often don’t know their pets are overweight.

APOP founder Dr. Ernie Ward, on the results of the organization’s 2011 survey of pet owners:

The most distressing finding in this year’s study was the fact that more pet owners are unaware their pet is overweight. 22 percent of dog owners and 15 percent of cat owners characterized their pet as normal weight when it was actually overweight or obese. This is what I refer to as the “fat pet gap” or the normalization of obesity by pet parents. In simplest terms, we’ve made fat pets the new normal.

  1. Even if they’re well-loved, overweight and obese pets generally have issues with their temperaments.

As much as people may cherish their heavyset animals, and as eager as many people are to celebrate internet-famous pets with high BMIs, obesity generally lowers companion animals’ vitality and increases emotional disturbances. A canine study in 2012 found that traits like aggression and anxiety were lowered, while sociability and enthusiasm increased, among dogs that successfully shed their excess weight. This kind of animal research is significant, because if a pet owner doesn’t know her cat is overweight or obese—and if she incorrectly assumes that a chunky cat is a happy cat—she’s not likely to administer a weight loss regimen that could save the animal’s life. And the knowledge that weight problems in animals cause emotional and physical harm is a crucial step in tackling the global pet obesity epidemic.

  1. The good news: It’s a great time for people to establish habits that will help them, and their pets, live more healthily.

This is the time of year when people everywhere have resolved to shed their excess holiday weight. But research shows that including your pets in a brisk walk, run, or playtime develops habits that will benefit both at the same time.

Animal research has led to important conclusions about obesity, weight management, diet, and exercise. And more animal research will help pet owners better assess, monitor, and treat issues involving diet and weight—giving them more time, and more quality time, with their companion animals.