Why is Etiological Prevention the Only Way to Reduce Cancer Incidence?

Years of research confirm that etiological prevention—identifying and mitigating cancer-causing risk factors and pinpointing susceptible populations—is the most effective approach to reducing cancer incidence.

The peak age for cancer diagnoses typically falls at 65 or older, with rates influenced by a wide array of factors, including demographics, nutrition, genetics, environment, lifestyle, economic conditions, and education. Among these, smoking stands out as a significant contributor to cancer risk.

Approximately 30% of cancers are linked to prolonged smoking, with a particularly strong correlation to lung cancer. The risks increase with factors such as smoking quantity, depth of inhalation, age at onset, duration of smoking, and the tar content in cigarettes. Smoking is also associated with cancers of the respiratory, digestive, and urinary systems, as carcinogens can be absorbed through the lungs and distributed throughout the body, leading to cancers of the larynx, esophagus, mouth, bladder, kidneys, and pancreas.

Improved living conditions have led to a greater focus on health, and certain lifestyle changes—such as refrigeration and a reduction in smoked and pickled food consumption—have contributed to declines in gastric and esophageal cancer rates. Similarly, better hygiene practices and regular gynecological screenings have driven down cervical cancer rates among women.

However, dietary changes pose new challenges. The shift towards Westernized diets, the popularity of fast and fried foods, excessive calorie intake, and declining physical activity have led to an increase in obesity—a major risk factor for colorectal, breast, kidney, and pancreatic cancers.

Epidemiological studies also indicate that diabetes is a significant risk factor for various cancers. Diabetes prevalence in China has surged from 0.67% in 1980 to 12.8% in 2020, potentially contributing to rising rates of colorectal, pancreatic, and breast cancers.

Additional factors like infections and carcinogenic exposures also play a role. Helicobacter pylori infection, for instance, is a known cause of gastric cancer, while hepatitis viruses are linked to liver cancer. Exposure to ionizing radiation and intense UV rays, especially from the sun, can increase skin cancer risk.

Preventive strategies targeting these risk factors are essential to slowing the rise in cancer rates and promoting healthier, longer lives.