Dogs lose weight on healthy, positive diet, study finds

Illinois USA January 27 ANI A new study of overweight dogs fed a high-protein, high-fiber diet for 24 weeks found that the dogs' body composition and inflammatory markers changed over time in ways that parallel the positive changes seen in humans on similar diets.

The dogs lost weight without losing any muscle mass, and their serum triglycerides, insulin and inflammatory markers all decreased with weight loss.

All of the changes are beneficial, said Kelly Swanson, professor of animal sciences at the University of Illinois Urbana-Champaign.

Previous studies had shown that overweight and obesity lead to a shorter lifespan and a lower quality of life in dogs and humans, Swanson said.

He said that there are some problems that occur in humans with obesity that are also found in pet dogs.

There's added stress on the joints, there's an intolerance to exercise and heat, there's also glucose intolerance, insulin resistance. He said that obesity is a big factor in the case when you look at pet insurance claims.

Swanson said that the study was unusual in that it also measured changes in the dogs' faecal microbiota over the course of losing weight.

Even though there are similarities in dog and human metabolism and digestive processes, dogs and humans differ in the species of microbes that inhabit the gut, he said. These microbes perform similar functions.

They metabolize proteins, carbohydrates and other molecules that are derived from food but escape digestion by the host, and they break down fibre to produce short-chain fatty acids that are important in regulating glucose and appetite, reducing inflammation, bolstering the immune system and providing energy to cells in the colon.

Swanson said that some of the microbial changes observed in the dogs were difficult to interpret, but a reduction in faecal ammonia was likely beneficial, and probably the result of eating less protein on the calorie-restricted diet.

He said that high concentrations of ammonia are toxic.

Dogs that lost weight also had increases in the proportion of bacteria in the Allobaculum genus. A higher Allobaculum population correlated with an increase in faecal butyrate, a short-chain fatty acid that is a byproduct of the fermentation of dietary fibre. Previous studies have shown that butyrate has anti-inflammatory and anti-carcinogenic effects in the gut.

The total short-chain fatty acid concentrations did not change over time. The researchers reported that most of the organic acids are absorbed and not excreted.