Background: Obesity is an important health concern facing our world for a while. Curcumin is a yellow substance produced by curcuma plant, with antioxidant, anti-inflammatory and insulin-like actions in animals. Itshowed very promising results in the control of rheumatoid arthritis more than the non-steroidal anti-inflammatory drugs which may give new hope.
 Aim of the work:  Herbal medicine has been proved to be effective in the reduction of comorbidity of some diseases. Based on the previous reports; liver, lung and heart were selected to be studied in this article to investigate the effect of obesity on these vital organs and the possible protective role of curcumin.
Material and Methods: Eighteen rats were equally divided into control, obese and curcumin-treated groups. The control rats received a standard diet, the obese group received a high-fat diet, the curcumin group was fed a fatty diet mixed with curcumin. After 8 weeks, all rats were anaesthetized, liver, heart and lung were dissected. The specimens were processed for paraffin sections. The slides were stained with hematoxylin-eosin (HE), Masson's trichrome and periodic acid schiff stains. Oxidative marker; malondialdehyde (MDA) was measured in the tissues of the liver, lung and heart.
Results: The liver in obese rats showed degenerated cells, increased collagen and glycogen percent. However, the curcumin-treated group showed less fibrosis and glycogen deposition. The lung sections showed fibrosis and increased mucin in obese rats but the curcumin-treated group exhibited less fibrosis and secretions. In contrast to the previous organs, the heart showed less glycogen content in obese rats, this decline was improved in the curcumin-treated group.
 Conclusion: the current studyhighlighted the structural changes that could be induced in some organs by obesity and clarified the possible protective role of curcumin as one of the novel agents in herbal medicine.