Effect of a homemade diet compared to a commercial diet on glycaemic variability and glycaemic control assessed by continuous glucose monitoring system in diabetic dogs: a randomised crossover study

Objectives: To evaluate the effects of a homemade diet (HMD) and a commercial diet (CD) on glycaemic control and glycaemic variability (GV) of diabetic dogs monitored with FreeStyle Libre continuous glucose monitoring system (CGMS). Methods: Prospective randomised crossover study including ten client-owned diabetic dogs on insulin treatment with good glycaemic control. Dogs were randomly assigned to receive either a moderate-fibre (total dietary fibre on a dry matter basis [TDF]: 8.6%) HMD or a high-fibre (TDF: 18%) CD in a 2x6-week period. Dogs were re-evaluated every 2 weeks. Clinical and clinicopathological variables, selected CGMS-derived and GV metrics, glucose nadir, and post-prandial hyperglycaemia were recorded. Differences between diets were analysed by a repeated measure ANOVA fitting a crossover design with pairwise comparisons. Results: There were no differences in insulin dose and glycaemic control levels between the two dietary period. The HMD significantly reduced serum cholesterol concentration (mean difference: 76; 95% CI: -51.97 to 204). The percentage of time above glucose range (TAR%) was significantly lower (mean difference: 22.5; 95% CI: 1.08 to 43.9) and the percentage of time below range (TBR%) higher (mean difference: -6.9; 95% CI: -12.4 to -1.38) during the HMD period. The percentage of time in range (TIR%) and GV metrics were not different between the two diets. Clinical significance: The HMD and CD can be considered valid dietary options in diabetic dogs. The results suggest that, with regard to the diets examined, the HMD might have a more effective glucose-lowering effect compared to the CD.