The causes of stomachache in young people may be as follows:

1. Irregular diet: Young people may be under great pressure from work or study, leading to irregular diet, excessive drinking or Eating spicy, greasy, and irritating foods can cause excessive gastric acid secretion or irritate the gastric mucosa, causing stomach pain.

2. Stress and anxiety: Long-term stress and anxiety can cause gastrointestinal tension, affect the digestive function of the gastrointestinal tract, and cause stomach pain.

3. Acid reflux: Acid reflux is a symptom caused by the reflux of food and acid in the stomach into the esophagus or throat, irritating the mucosa of the esophagus and throat, and is often accompanied by stomach pain.

4. Digestive system diseases: Digestive system diseases such as gastritis, gastric ulcer, cholecystitis, cholelithiasis, etc., may cause stomach pain.

5. Adverse drug reactions: Some adverse drug reactions may cause stomach pain, such as non-steroidal anti-inflammatory drugs, antibiotics, etc.

6. Long-term smoking: The chemicals in tobacco stimulate the gastrointestinal tract and cause stomach pain.

7. Infection: Infections such as bacteria and viruses may also cause stomach pain.

In summary, the causes of stomach pain in young people may be diverse and require analysis and diagnosis based on specific circumstances. If stomach pain occurs frequently or lasts for a long time, it is recommended to seek medical treatment in time for early diagnosis and treatment.