What is the cause of heart burns?

Heartburn is primarily caused by acid reflux, where stomach acid flows back into the esophagus due to a weakened lower esophageal sphincter. Factors contributing to this condition include overeating, consuming spicy or fatty foods, obesity, smoking, and certain medications. Stress and lying down after meals can also exacerbate symptoms. Chronic heartburn may indicate gastroesophageal reflux disease (GERD), which requires medical attention.