Which diet is best for your dog? Surprising new insights revealed

Feeding a dog is part habit, part instinct. Yet, every scoop of food tells the body how to work.

The DogRisk research group at the University of Helsinki decided to look deeper into that connection. Their new study compared two feeding styles – a carb-loaded kibble and a fat-rich raw meat diet.

What the team has discovered could change how we think about pet nutrition.

Comparing dog diets

Forty-six Staffordshire Bull Terriers took part in the study. Some ate kibble made of rice and maize. Others got a raw diet filled with fat, meat, and protein but no carbohydrates.

The diets were continued for around four and a half months. During that time, the researchers tracked blood sugar, cholesterol, insulin, triglycerides, and ketones.

The contrast was strong. Kibble-fed dogs had higher blood sugar, bodyweight, and lipid levels.

Dogs on the raw diet showed the opposite pattern. Their blood sugar dropped. Their cholesterol went down. Ketones, which fuel the body when fat becomes the main energy source, rose sharply.

How metabolism changed

The raw diet triggered something interesting – a metabolic switch called nutritional ketosis. This happens when the body starts burning fat instead of sugar for fuel.

Despite the diet being rich in fat, cholesterol levels fell instead of rising. The kibble group, however, showed more HDL, LDL, and VLDL cholesterol. That pattern fits with what happens in humans when the liver converts excess carbohydrates into fat.

Another finding caught attention. Glucagon, a hormone that raises blood sugar, decreased in the raw-fed group. It suggests their bodies didn’t need to keep producing glucose. Their energy came more efficiently from fat.

The triglyceride-glucose index, a marker for insulin resistance, also improved in this group.

What the researchers found

“Interestingly, the kibble diet was associated with changes often linked to adverse metabolic health, while the raw food diet promoted metabolic responses generally considered favorable,” said Dr. Sarah Holm, the study’s lead researcher.

“More research is needed to understand the long-term health implications of these two feeding strategies.”

Dr. Anna Hielm-Björkman, who leads the DogRisk group, said this is a great example of One Health research.

“Our findings reflect similar, and sometimes controversial, human studies suggesting that fat-rich diets actually lower cholesterol and triglycerides, while carbohydrate-rich diets raise blood lipids and long-term blood sugar – a known precursor to type 2 diabetes in humans,” said Dr. Hielm-Björkman.

The evolution of dog diets

Long before kibble existed, dogs lived as hunters and scavengers. Their ancestors, wolves, ate mostly protein and fat.

Over time, domestication gave dogs more enzymes to process starch, but not enough to change their natural energy preference.

Most kibble today still contains more than half its calories from carbohydrates. That doesn’t match the biology of a species built for fat-based energy.

Raw diets, meanwhile, mirror the food dogs once thrived on. Earlier studies have already linked raw feeding to better digestion, improved coat quality, and lower inflammation.

This new study goes further. It shows that feeding choices can directly shape metabolism and possibly lower disease risks.

Broader implications of the study

The results fit a wider picture seen in humans. Low-carbohydrate, fat-rich diets often improve insulin sensitivity and reduce triglycerides. The same appears true for dogs.

The raw-fed group’s higher ketone levels show the body’s flexibility – its ability to shift from sugar-burning to fat-burning when diet allows it.

Kibble-fed dogs, on the other hand, stayed in a glucose-driven state. This constant sugar use may keep blood sugar and fat levels high.

Over time, it could mimic early signs of metabolic syndrome, a condition linked to obesity and insulin resistance in both dogs and humans.

Lessons from different dog diets

Dogs share similar metabolic systems with humans. That’s why the researchers see them as useful models for studying diet and chronic disease.

The findings bridge veterinary science and human nutrition. If fat-based diets can stabilize energy metabolism in dogs, the same mechanisms might help humans manage metabolic conditions more effectively.

This study isn’t pushing one diet as perfect. Instead, it shows that food does more than fill a bowl – it directs biology. The type of energy a body uses depends on what it receives. For dogs, less starch and more fat may mean better balance.

Feeding isn’t just about taste or convenience. It’s about chemistry, energy, and long-term health.

The DogRisk team’s findings remind us that the food we choose – whether for dogs or ourselves – can quietly decide how the body performs every single day.

The study is published in The Veterinary Journal.

—–

Like what you read? Subscribe to our newsletter for engaging articles, exclusive content, and the latest updates. 

Check us out on EarthSnap, a free app brought to you by Eric Ralls and Earth.com.

—–