In the present study, chitosan supplementation decreased plasma glucose, increased GLUT4 translocation, and improved oral glucose tolerance test and insulin tolerance test results, suggesting that the hyperglycemia and insulin resistance induced by a long-term high-fructose diet can be alleviated by chitosan; this effect is possibly through the activation of AMPK phosphorylation in an HFD-fed rat model. The gene discussed is SLC2A4; the disease is Hyperglycemia.