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Cancer Risk and Prevention

There's no sure way to prevent cancer, but you can help reduce your risk by making healthy choices like eating right, staying active, and not smoking. 

Learn about Cancer Causes

Understanding the Causes of Cancer

Find out what we know about the factors that can affect your cancer risk.

Genetics and Cancer Risk

Some types of cancer run in certain families, but most cancers are not clearly linked to the genes we inherit from our parents. Gene changes that start in a single cell over the course of a person's life cause most cancers.

Body Weight and Cancer Risk

Being overweight or obese can have far-reaching health consequences, including raising your risk for certain types of cancer. Learn more about the link between body weight and cancer here.

More in Risk and Prevention

Radiation Exposure and Cancer Risk

Exposure to radiation can increase the risk of cancer. Learn more about the different types of radiation and how exposure might affect your cancer risk.

Chemicals and Cancer

Get the facts about these known, possible, and unlikely environmental causes of cancer.

Infectious Agents

In the United States and other developed countries, a small portion of cancers are thought to be linked to infections. Learn more here.

Medical Treatments that Might Affect Cancer Risk

Some types of tests and treatments may actually increase a person's risk of developing cancer. Get the facts about possible links between certain medical procedures and cancer.