5 Reasons the Obesity Epidemic is Spreading to Animals

By Sara Novak, Planet Green

The American obesity epidemic has become a hot topic of news. And with good reason considering we’re the fattest nation in the world and we’re only getting fatter. But a new study led by David Allison, a biostatistician at the University of Alabama at Birmingham, published in the Proceedings of the Royal Society B and reported in Scientific American has shown that animals are experiencing the same problem. And this isn’t just household pets as you may expect, it’s animals that live anywhere close to humans.

Allison and his team examined the changes in weight of 24 different species, 12 male and 12 female. Some of the varied species included household pets like cats and dogs as well as feral rats that live near humans. The researchers tracked weight gain per decade.

According to the study:

Because there were no clear guidelines for what animals should weigh, the authors defined obesity as the weight above the 85th percentile in each group at the earliest time point for which they had data. Both the percentage increase in body weight and the odds of an animal being overweight in a given population showed a strong trend upwards.

So what’s causing animals to get fatter? Why are dogs and cats becoming more susceptible to weight gain along with farm animals and rodents? Both the study authors and other relevant animal experts came to conclusions about why so many species were fattening up, many of which may surprise you.

Related: American Pets Getting Fatter

1. Richer Table Scraps

According to the study:

The more than 40 percent jump in body weight in feral rats scavenging on the streets of Baltimore may reflect the increasing richness of their diet as they feed on our more calorie-dense refuse.

Animals that feed on our table scraps are getting as fat from it as we are. Fifty years ago our table scraps were less likely to be an extra value meal from your local fast food chain and this is true of household pets as well. If you’re feeding them human food and you don’t eat healthy, they won’t be eating healthy either.

2. An Indoor Lifestyle

Nearly 89 million American pets are overweight or obese according to the Association for Pet Obesity Prevention. And just like in humans, such weight problems put them at risk of diabetes, arthritis, high blood pressure, and a multitude of other diseases.

Like person like pet, our household pets follow our directions. If you’re active and love playing outside, you’re more likely to take your pet on walks, throw the ball outside, and take them on hikes. On the other hand, our increasingly indoor society means that animals are spending more and more time asleep on the couch while we watch television. Your cat may watch a bird on the tube, rather than venturing outside to catch it. According to Cairn Rescue, outdoor cats and house cats that roam outside typically do not get fat. It’s cats that are left indoors that suffer from boredom and lack of exercise.

Related: Jog With Your Dog

3. Toxins in Our Water Supply

I’ve talked about pollution in our water supply before that results from a range of toxins and pharmaceuticals. According to the New York Times, an EPA survey of 139 streams around the country revealed that 80 percent of samples contained residues of drugs like hormones, painkillers, blood pressure medicines, or antibiotics. Allison and his team found that toxins in the water supply disrupt the endocrine system of animals which can literally slow down a mammal’s metabolism.

4. Spoiling Our Pets

We tend to spoil our household pets especially if we feel guilty for leaving them alone for much of the day while we’re at work. Some pet treats contain too many calories, just like human snack foods. Some of the larger dog chews can contain as much as 600 calories, which for some dogs is more than a daily allowance of calories, according to the Association for Pet Obesity Prevention. Dog treats are nutrient dense and this coupled with feeding our dogs junk food from the table makes for an overweight pup.

5. Disrupting Hibernation and Migration

Until recently, my advice to an overweight human would have been following the time honored advice of our fellow mammals and bird species: eat when you’re hungry and stop when you’re full and get some exercise each day. This is because animals genetically listen to their bodies more than humans. The only problem is that we’ve disrupted the habits of animals so much that even they keep getting fatter. According to the study, certain environmental factors could be affecting body-weight cycles in migrating and hibernating animals. In the wake of climate change, for example, some animals have stopped hibernating and others have shortened their seasonal migration routes. Migration routes are threatened by habitat destruction as well. I wrote over at TreeHugger that such destruction presents an acute threat to the survival prospects of the pronghorn antelope in the American west for example. Poor land use can fragment the pronghorn’s migration pattern and adversely affect the species’ natural cycles. When they don’t travel as far, they’re don’t burn as many calories.

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Mike P.
Mike P.4 years ago

The name of this list is misleading. 3 reasons are correct, 2 have no reason for being here. All of these reasons are alarming for the health of animals. However, I'd be more concerned with the increase in incidence of cancers in the animals most affected by numbers three and five, than worried about their obesity.

I would want to know ANY specific data that says otherwise.

Emily Drew
Emily Drew5 years ago

I don't understand how someone could let their child (animal or human) become very overweight or obese. If someone is starving their child it is considered cruelty and neglect yet if someone over feeds their child and lets them sit around and not exercise (once again this is for human or animal child) and yet that is not considered cruelty and neglect!? Either way you are killing your child!

rene davis
irene davis7 years ago

thank you.

Susan S.
Susan S7 years ago

Interesting. Of our three cats only one is chubby, and he is the most mellow as well.

Roisin S.
Roisin S7 years ago

too much food and lack of exercise, same reason humans are getting fatter

Lika S.
Lika P7 years ago

My great grandparents built their own farm by hand. They also used to have dogs, none of the family were overweight. Until now, of course. I think we need to adopt the philosophy of work hard, play hard. We don't do farming like they used to. We now have office jobs and what not. Without the extra workout, we can't eat like farmers and not expect to get fat. Just remember, depending on your body type, if you exercise or not, what you do for a living, etc, all depends on what you can/can't eat.

With the prepackaged food along with processed food, comes the problem also, because they're not made to be nutritious, they're made to be convenient. Eat real food. The process of cooking can help you lose weight because you're working for it. Plus it's healthier and tastier.

Nellie K A.
Nellie K Adaba7 years ago

It's because of stupid sedentary humans that animals get fat because, some don't have time to walk them outside...

Barbara Erdman
Barbara Erdman7 years ago

Thanx good article facts

Lori K.
Lori K7 years ago

All of this makes perfect sense. My dogs are not obese, because they walk with us down the cliffs to the dog beach, hike with us, chase tennis balls, and nonstop romp with each other.

Some of my cats are obese, but surprisingly only the ones that are NOT content to remain indoors only. The semi-feral, outdoors only kitties are all slim, the indoors only are normal, but of the 3 indoor kitties who insist on slipping out whenever we let down our guard, 2 are obese.

I hate letting any cats outside, especially friendly ones who do not disappear at the first whiff of an unfamiliar person. Look at all of the petitions and stories on care2 alone targeting freaks who like to torture cats (usually on youtube, SICKO PERVERTS).

I appreciate the information, but please be careful. Your comment about indoor only cats obesity might induce some people to let their (formerly indoor only) cats go outdoors. This might help their obesity, but it certainly won't help their longevity if they are hit by a car, or grabbed by a sadist with ulterior motives.

Past Member 7 years ago

no surprise....but i do need to get up and get busy...means less time for care2...