Metabolic and Appetite Effects of Fructose and Glucose in Subjects with Type 1 Diabetes: A Randomized Crossover Clinical Trial.

Background: Fructose has been widely used for producing lower post-infusion glucose increase than other carbohydrates, but it seems that it promotes an increase in post-infusion triglycerides.

Objective: The present study investigated the effects of fructose and glucose in metabolic variables and appetite sensations in patients with type 1 diabetes mellitus (T1DM).

Methods: This is a single-blind, randomized, and crossover study (washout of 1-5 weeks), which evaluated 16 adult T1DM patients, accompanied at University Hospital. After eight hours of overnight fasting, there was an assessment of capillary blood glucose, anthropometric variables, appetite sensations, and laboratory tests (glycemia, lipemia, leptin and glucagon) were conducted. Subsequently, they received 200mL of solutions with water and 75g of crystal fructose or glucose. Appetite sensations and capillary blood glucose were evaluated in different post-infusion times. Blood was drawn after 180 minutes for the laboratory tests.

Results: Blood glucose increased after the intake of both solutions, but glucose induced a higher elevation. None of them increased triglycerides or glucagon. Glucagon maintenance was similar among the solutions. Furthermore, both solutions reduced leptin and increased fullness, but only fructose increased the lack of interest in eating sweets.

Conclusion: Fructose induced a smaller increase in postprandial blood glucose than glucose, without changes in triglycerides and glucagon. In addition, leptin levels and appetite sensations were similar to glucose. Other studies are needed in order to confirm these findings, especially in the long term, so that their use becomes really reliable.