Reducing the risk of certain cancers may be possible through dietary (see Prevention and Treatment of Cancer: Diet and Cancer) and other lifestyle changes. How risk can be reduced depends on the specific cancer. Tobacco use is directly associated with one third of all cancers. Not smoking and avoiding exposure to tobacco smoke can greatly reduce the risk of lung, kidney, bladder, and head and neck cancer. Avoiding the use of smokeless tobacco (snuff, chew) decreases the risk of cancer of the mouth and tongue.

Other lifestyle changes reduce the risk of several types of cancer. Decreasing alcohol intake can reduce the risk of head and neck, liver, and esophageal cancer. A reduced intake of fat in the diet appears to decrease the risk of breast and colon cancer. Avoiding sun exposure (especially during the middle of the day) can reduce the risk of skin cancer. Covering exposed skin and using sunscreen lotion with a high sun protection factor (SPF) against ultraviolet light also help reduce the risk of skin cancer. Use of aspirinSome Trade Names
BAYER
and other nonsteroidal anti-inflammatory drugs (NSAIDs) reduces the risk of colorectal cancer. Papanicolaou (Pap) tests can help prevent cervical cancers by detecting precancerous changes in cells of the cervix.

Vaccination can prevent certain types of cancer that are caused by viruses. Cervical cancer is caused by infections with certain strains of sexually transmitted human papillomavirus (HPV). Vaccination against HPV before the first sexual encounter (see Immunization: Human Papillomavirus) can largely prevent cervical cancer. HPV infection may also increase the risk of anal cancer and some forms of head and neck cancer. As another example, infection with hepatitis B virus increases the risk of liver cancer; vaccination against hepatitis B virus can help prevent this type of cancer.

Preventing Cancer
According to the American Cancer Society, the risk of developing certain cancers may be reduced by making lifestyle changes. Measures known to reduce the risk of cancer: Avoiding smoking or exposure to tobacco smoke Avoiding occupational carcinogens (for example, asbestos) Avoiding prolonged exposure to sunlight without sunscreen protection Avoiding excessive alcohol intake Avoiding use of hormone therapy (for example, estrogen and progesteroneSome Trade Names CRINONE ENDOMETRIN ) for symptoms of menopause Measures that may reduce the risk of cancer: Limiting intake of high-fat foods, particularly from animal sources (for example, high-fat meats and whole-fat dairy products) Increasing intake of fruits and vegetables Being physically active Keeping weight below the obese level

Early detection of cancerous or precancerous growths can save lives. For women 40 years of age or older, having yearly mammograms can help detect breast cancers while they are still curable. For people 50 years of age or older, having a colonoscopy (inspection of the large intestine through a flexible viewing tube) every few years can detect polyps and early cancers of the colon.

Last full review/revision August 2007 by Bruce A. Chabner, MD; Elizabeth Chabner Thompson, MD, MPH