High-Protein, High-Fiber: This Diet May Be Beneficial To Overweight Dogs

Is your dog on the heaver side? Feeding overweight dogs a restricted high-fiber, high-protein diet may help yield positive changes, a new study has found.

Even dogs can be overweight or obese. In a 2018 survey by the Association for Pet Obesity Prevention, some 55.8% of dogs in the U.S. are either obese or overweight, according to the American Kennel Club (AKC). A 2021 survey of more than 1,000 dog parents also found that almost 40% of dogs gained weight during the stay-at-home orders.

Just like in humans, this extra weight can cause quite a few health issues -- from canine diabetes to arthritis and heart problems. Obesity may even make them more likely to develop diseases and shorten their lives, the VCA (Veterinary Centers of America) Animal Hospitals noted.

For their study, published in the Journal of Animal Science, a team of researchers sought to find the effects of a "restricted feeding of high-fiber, high-protein (HFHP) diet" on overweight dogs. To do this, they fed 12 spayed female dogs that were overweight with the HFHP diet during a 24-week period.

They found that the dogs lost 31.2% of their initial body weight and also had decreased fat percentage and fat mass. Further, "many serum metabolites and hormones" were also altered with the weight loss.

This is quite similar to the change that happens in humans on such diets, the University of Illinois Urbana-Champaign (UIUC) noted in a news release. The dogs ended up achieving a healthier weight without losing much muscle mass and had reduced inflammatory markers.

The researchers also looked at the dogs' gut microbiota and found some "significant changes." Although not all of the changes were easy to interpret, the researchers surmised that some of them were likely "beneficial."

For instance, the dogs that lost weight had increases in bacteria of the genus Allobaculum. As the university explained, higher Allobaculum populations have been linked to an increase in butyrate, a shortchain fatty acid that has been shown to have "anti-inflammatory and anti-carcinogenic" effects. Furthermore, they also had reduced fecal ammonia.

"High concentrations of ammonia are toxic," professor Kelly Swanson of UIUC, the study lead, said in the UIUC news release, adding that this change was likely a result of eating less protein under the restricted diet.

"Our results suggest that restricted feeding of an HPHF diet and weight loss promotes fat mass loss, minimizes lean mass loss, reduces inflammatory marker and triglyceride concentrations, and modulates fecal microbiota phylogeny and activity in overweight dogs," the researchers wrote.

This also provides valuable insight on the similarities and differences of humans and dogs' microbiota, the university stated, noting that most studies on the matter are focused on humans.