Ask the experts
What is the number one cause of cancer?
Cancer is actually a complex group of individual diseases, each with different causes and effects. At the core of causing cancer are changes that occur in the genetic material within cells, the DNA. These changes, or mutations, lead to abnormal, uncontrolled cell proliferation. Cancer mutations can be caused by a variety of situations and exposures. Causes of cancer include cancer-causing chemicals, called carcinogens, such as tobacco smoke, chemotherapies, asbestos, benzene, vinyl chloride, and many more, as well as environmental factors, such as ultraviolet light, pollution, and hepatitis B. For many forms of cancer, genetic inheritance plays a significant role in causing the disease because of inherited gene mutations.
For more information, read our full medical article about cancer signs, symptoms, treatment, and prognosis.
"Risk Factors for Cancer"
National Cancer Institute