The effect of two diets with different carbohydrate content on glucose markers in dogs

Considering that dogs originate from wolves, who are carnivores, one may speculate whether high amounts of carbohydrates are beneficial to dogs’ health. The aim of this master’s thesis was to compare two different type of diets regarding glucose markers in dogs. Fasting blood samples were taken before and after a diet intervention for the analysis of blood glycosylated hemoglobin (HbA1c), glucose, insulin and glucagon concentrations to compare the differences between dogs fed a high-carbohydrate diet (dry food diet) and a diet containing no dietary carbohydrates (raw food diet). Also bodyweight was evaluated before and after the trial. This master’s thesis was part of a larger study that investigated associations between diet and atopic dermatitis in Staffordshire bull terrier dogs at the University of Helsinki. The dietary intervention lasted for 50-188 days (median 136 days). The high-carbohydrate diet contained: 42% carbohydrates, 23% proteins and 34% fats of total metabolic energy dry matter. Two different low-carbohydrate diets were used. One was a pork-chicken-lamb diet, which contained: 0%: carbohydrates, 25% proteins and 75% fats of total metabolic energy dry matter, and the other was a beef-turkey-salmon, which contained: 0% carbohydrates, 30% proteins and 70% fats of total metabolic energy dry matter. Water was allowed ad libitum. The results showed that feeding a carbohydrate-rich dry food to pet dogs for 4,5 months increased the percentage of HbA1c. In contrast, a raw food diet with low carbohydrate content did not affect the percentage of HbA1c. Both blood glucose and glucagon concentrations decreased within the raw food diet group; while they were not affected in the dry food diet group. No statistical changes in insulin concentrations were found. Based on the results of this study it can be concluded that a high-carbohydrate diet, and a low-carbohydrate, respectively, have different effects on glucose metabolism in dogs. More research is needed to understand how this affects the dog’s health.