Causes

• When you eat or drink, the food or liquid will pass from your mouth, into your esophagus and then into your stomach.
  
  
• There is a valve mechanism at the top of your stomach called the lower esophageal sphincter (LES), which normally opens and closes to let food into the stomach. It also stops the acid in the stomach from moving back into the esophagus. 
  
  
• If the LES does not work properly, acid is allowed to pass up into the esophagus. This is called reflux. The esophagus does not have the same protective lining as the stomach, so the acid, produced in the stomach, causes heartburn. Over time the acid will cause damage (erosions - a shallow open sore limited to the inner lining of esophagus or rarely deeper lesion called ulcer) to the inner lining of the esophagus and this condition is known as reflux esophagitis.

If you suffer from heartburn and reflux esophagitis, you may find that certain things make you feel worse. These include: 

• Food 
  
  
  • Certain foods or drinks, including alcohol, fruit juices, highly spiced foods, onions, peppermint, pepperfruit, coffee and chocolate. 
    
    
  • Large meals 
    
    
  • Fatty foods 
    
    
  • Eating too close to bedtime
    
    
• Smoking 
  
  
• Pregnancy 
  
  
• Medical conditions 
  
  
  • If the muscle in the LES does not work properly. 
    
    
  • If the stomach produces too much acid, it will be more likely that acid may leak into the esophagus. 
    
    
  • Patients with hiatal hernias have an increased risk of suffering from acid reflux. An hiatal hernia is where a small part of the stomach sticks out above the diaphragm into the chest. 
    
    
  • Obesity. 
    
    
• Some medicines can affect the LES so that it does not work properly. These include aspirin, oral contraceptives, tetracycline and iron supplements. 
  
  
• Wearing tight clothes around the stomach may make acid reflux worse. 
  
  
• Exercise or bending may bring on acid reflux.
  

Although reflux esophagitis is most commonly caused by reflux of the acidic stomach content, the esophagus can be damaged by other factors, for example a fungal or viral infection, irradiation (such as radiation therapy during cancer treatment) or swallowing caustic substances (such as bleach).