Acid reflux is the movement of acid from the stomach into the esophagus. This is because of a faulty Lower Esophageal Sphincter. This is the valve that stops food from leaving the stomach after you've eaten. Many factors can contribute to this problem. These are but a few of the causes of Acid Reflux.
Pregnancy
During the last months of pregnancy the stomach is pushed up by the enlarging baby. This can cause some acid to find its way up into the esophagus. This can not be cured by taking antacids. The good news is that after birth the problem disappears. You can control Acid Reflux during pregnancy by eating small amounts of food but frequently. A large meal ingested at once will worsen the situation.
Obesity
This can also cause acid reflux. The cure of course is to lose those extra pounds and your problems are gone forever.
Asthma
Study still cannot explain how this happens but some research has shown that excessive coughing can worsen the problem of acid reflux.
Hiatal Hernia
Hiatus is a small hole through which the esophagus passes through the diaphragm into the stomach. Its supposed to fit so well that there is no space left on the sides. Sometimes this is not the case. And if it so happens one can have a problem of Acid reflux. It is especially common with people over the age of 65.

Overeating
This causes Acid Reflux due to the excess acids produced by the stomach lining to digest the ingested food. Some of this acid can find its way up the gut system. If you experience Acid Reflux at bed time you should try sleeping on an empty stomach or eat a few hours before bed time to reduce the chances of getting acid reflux.
Angela Mwema Researches and Reports on Acid Reflux. For More Information on Acid Reflux Disease, Visit Her Site at ACID REFLUX DISEASE