Acid reflux is often accompanied with heartburn and belching after meals. Lying down after a meal will aggravate the acid reflux or the heartburn.
Hiatal hernia can be a cause for this problem and is the result of weakened connective tissue that bulges through the diaphragm in and around the esophagus. If the valve between the esophagus and stomach becomes weak, the stomach acid then refluxes up the esophagus. Eating habits are a cause for acid reflux.
Eating large meal, meals late in the day or meals rich in saturated fats (especially fried foods and frying oils) often increase the problem because they are long to digest. Iceberg salad also slows down digestion.
A lack of fiber from fruits, vegetables and wholesome grains has a big impact on the elimination of toxins, which overload the liver. Studies show that an overloaded liver produce bile that is a lot more irritant for the digestive tract. If the person does not chew properly, the food has a tendency to backwash from the duodenum, back into the stomach, bringing some bile along. It can even go all the way up the esophagus if the valve at the top of the stomach becomes weak from all this exposure to bile. Those studies show that bile is a major source of irritation for the stomach and esophagus.
Alcohol, coffee, cigarettes and spicy foods also increase the irritation of the stomach and esophagus. By consequence it is very important to chew food properly.
Putting down the fork between bits can help slow down.
Listening to relaxing music during meals can also help slow down and chew properly.
Here is more information on acid reflux