Whereas the causes of stomach cancer are not clearly understood, risk factors for cancer have been studied extensively. These include faulty dietary habits like high salt intake, preserved meat, lifestyle habits like smoking, obesity, environmental factors like infection by Helicobacter pylori, Epstein Barr virus. Medical conditions like pernicious anemia, gastroesophageal reflux, gastric polyp also increase the risk of gastric cancers. Certain genetic risk factors predispose to stomach cancer increase the risk of familial gastric cancer.