Causes of stomach cancer

Stomach cancer (gastric cancer) begins when cells in the stomach lining grow out of control. The exact trigger in any one person is often unclear, but several factors raise the risk. Having a risk factor does not mean a person will get cancer.

Helicobacter pylori infection This common stomach bacteria is the strongest known risk factor. Long-term infection causes chronic inflammation and, in some people, precancerous changes. Treating the infection lowers the risk.

Diet-related factors

• High intake of smoked, salted and pickled foods
• Processed and red meats in large amounts
• Low intake of fresh fruits and vegetables
• Food contaminated with aflatoxins (molds in poorly stored grains)

Tobacco and alcohol Smoking roughly doubles the risk of stomach cancer, especially in the upper stomach. Heavy alcohol use adds risk.

Medical conditions

• Pernicious anemia (vitamin B12 deficiency from autoimmune gastritis)
• Chronic atrophic gastritis and intestinal metaplasia
• Stomach polyps of certain types
• Previous stomach surgery

Genetic and other factors

• Family history of stomach cancer and rare inherited syndromes
• Older age; it is more common over 50
• Men are affected more than women
• Obesity, especially for cancers near the food pipe junction
• Epstein-Barr virus in a small share of cases

Ayurvedic view (interpretive) Ayurveda describes chronic digestive disturbance and dosha imbalance leading to serious growths (Arbuda). This is a conceptual framework and does not identify cancer causes; modern risk factors above are the evidence-based ones.

When to see a doctor Long-standing indigestion, trouble swallowing, unintended weight loss, vomiting blood or black stools need prompt evaluation. Call 112 for severe bleeding or collapse.

Remember H. pylori infection, smoking and a salty, smoked diet are the main avoidable risks.