The present invention relates to a method for preventing or treating a metabolic disease, which comprises inhibiting HTR2A (5-hydroxytryptamine 2A receptor) or HTR3A (5-hydroxytryptamine 3A receptor). The inhibition of HTR3A leads to various advantageous efficacies for therapy of metabolic diseases, including resistance to obesity, decrease of lipid droplet size, increase of expression levels of thermogenic genes, increase of metabolic activities, increase of insulin sensitivity and decrease of LDL cholesterol and leptin.
