Acid reflux occurs when stomach acid flows back up into the esophagus, often caused by a weak or malfunctioning lower esophageal sphincter (LES) — the muscle that normally keeps stomach contents from traveling backwards. When this valve does not close properly or opens too often, acid reflux symptoms arise. Common causes and risk factors for acid reflux include:
- Eating large meals or fatty, spicy, or acidic foods (e.g., citrus fruits, tomatoes, chocolate, garlic, onions)
- Eating close to bedtime or lying down soon after meals
- Drinking coffee, alcohol, or carbonated drinks
- Smoking
- Being overweight or obese
- Pregnancy
- Stress and anxiety
- Wearing tight clothing around the abdomen
- Taking certain medications (e.g., aspirin, ibuprofen, muscle relaxants, blood pressure meds)
- Conditions such as hiatal hernia and connective tissue diseases like scleroderma
These factors can cause the LES to relax inappropriately, allowing stomach acid to travel upward, irritating the esophageal lining and causing the burning sensation known as heartburn or acid reflux.
In summary, acid reflux is caused mainly by the improper functioning of the LES combined with lifestyle, dietary factors, and certain medical conditions that increase stomach acid exposure to the esophagus.
