A randomized, double blind, controlled trial will be conducted in general intensive care unit (ICU) in Tehran, Iran. After a full review of the inclusion and exclusion criteria and explanation of the risks and benefits of the study, written consent form will be completed. The participants are 60 eligible hospitalized patients with enteral feeding in ICU, aged ≥ 18 years. Intervention patients will be received 0.3 g/kg/day of glutamine along with enteral formula for 10days and control patients will be received maltodextrin along with enteral formula for 10 days. Patients will be evaluated for plasma endotoxin and plasma zonulin.