Brief answer....you must get an endoscopy done. Detailed answer.... Hello, Thanks for the query. Gastritis is a clinical diagnosis but it should further be explored by getting an GASTROSCOPY done to look the inner lining of stomach directly. This way you can see whether you are suffering from H.PYLORI infection or not. H.PYLORI is a very common infection of stomach lining which can result in gastritis. Moreover your apprehension regarding cancer can also be sorted out,although I am quite convinced that you would not be having cancer. Talk to your doctor and get a GASTROSCOPY done. As far as your food is concerned,you have to avoid foods that irritate your stomach lining. Not all foods effect a person same way. You have to learn yourself which foods trouble you the most. In general following foods should be avoided... Alcohol,whole milk,chocolate milk,orange and grape fruit juices Spices like chillies,black pepper etc. Onion,garlic,tomato products,high fat meat,spicy cheeses,jalapeño etc. Eat fruits,whole grain,vegetables,fat free dairy products,lean meat chicken etc. Take your meal at least 2 hours before bed time. Take frequent small meals Take your medicines regularly. As far as time taken for healing of gastritis is concerned ,it may take  from few weeks to many months. H.PYLORI infection can be eradicated in two weeks time. I hope it helps,however you may revert to me for any further query. Best of luck Thanks

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