Having chronic gastritis does not necessarily mean having H. pylori infection. Chronic gastritis is not caused entirely by H. pylori infection, only that most of the chronic gastritis is due to H. pylori infection. Chronic gastritis may also be caused by dietary and environmental factors, such as a diet high in salt and lack of fresh vegetables and fruits, leading to atrophy of the gastric mucosa and causing chronic atrophic gastritis. In addition, autoimmune gastritis is also a type of chronic atrophic gastritis. Other exogenous factors, such as alcohol abuse, the use of non-steroidal anti-inflammatory drugs or certain irritating foods, may damage the gastric mucosa and lead to an attack of chronic gastritis. If H. pylori infection is present in patients with chronic gastritis, H. pylori eradication therapy needs to be given under the guidance of a gastroenterologist, as appropriate. Other types of chronic gastritis also require pharmacological treatment under the guidance of a specialist, if necessary.