It is commonly caused by the following: stimulation of food, frequent consumption of foods high in sugar, fat, spicy and stimulating foods or frequent consumption of drinks that promote the secretion of stomach acid such as coffee, strong tea and alcohol; long-term use of non-steroidal anti-inflammatory drugs such as aspirin, calcium antagonists and theophylline; changes in lifestyle habits and mental factors such as mental tension and depression; and digestive system diseases such as chronic gastritis, peptic ulcer and gastro-oesophageal reflux disease.