Causes and Risk Factors
The stomach acids are held in
the stomach by a muscular valve
known as the lower esophageal
sphincter (LES). The LES is located
at the border of the esophagus
and the stomach, below the rib
cage and slightly to the left.
It opens to allow food and liquids
into the stomach or to permit
belching, and it closes afterwards.
If the LES opens too often or
does not close tightly enough,
stomach acid flows back into the
esophagus, causing heartburn.
The acid backup becomes even worse
if the individual who is suffering
is lying down or bent over. Chronic
heartburn can indicate serious
problems and can manifest into
gastro-esophageal reflux disease
factors that can aggravate heartburn