Scientists study risk factors and protective factors to find ways to prevent new cancers from starting. Anything that increases your chance of developing cancer is called a cancer risk factor; anything that decreases your chance of developing cancer is called a cancer protective factor.
Some risk factors for cancer can be avoided, but many cannot. For example, both smoking and inheriting certain genes are risk factors for some types of cancer, but only smoking can be avoided. Risk factors that a person can control are called modifiable risk factors.
Coenzyme Q 10 is a compound that is made naturally in the body. The body uses it for cell growth and to protect cells from damage that could lead to cancer (see Question 1).
Animal studies have shown that coenzyme Q10 helps the immune system work better and makes the body better able to resist certain infections and types of cancer (see Question 5).
Clinical trials have shown that coenzyme Q10 helps protect the heart from the damaging side effects of doxorubicin, a drug used to treat cancer...
Many other factors in our environment, diet, and lifestyle may cause or prevent cancer. This summary reviews only the major cancer risk factors and protective factors that can be controlled or changed to reduce the risk of cancer. Risk factors that are not described in the summary include certain sexual behaviors, the use of estrogen, and being exposed to certain substances at work or to certain chemicals.
Factors That are Known to Increase the Risk of Cancer
Not smoking or quitting smoking lowers the risk of getting cancer and dying from cancer. Scientists believe that cigarette smoking causes about 30% of all cancer deaths in the United States.
See the following PDQ summaries for more information:
Lung Cancer Prevention
Cigarette Smoking: Health Risks and How to Quit
Certain viruses and bacteria are able to cause cancer. Viruses and other infection -causing agents cause more cases of cancer in the developing world (about 1 in 4 cases of cancer) than in developed nations (less than 1 in 10 cases of cancer). Examples of cancer-causing viruses and bacteria include:
Human papillomavirus (HPV) increases the risk for cancers of the cervix, penis, vagina, anus, and oropharynx.
Hepatitis B and hepatitis C viruses increase the risk for liver cancer.
Epstein-Barr virus increases the risk for Burkitt lymphoma.
Helicobacter pylori increases the risk for gastric cancer.