Merck Manual

Please confirm that you are not located inside the Russian Federation

honeypot link

Prevention of Cancer


Robert Peter Gale

, MD, PhD, Imperial College London

Last full review/revision Sep 2020| Content last modified Sep 2020
Click here for the Professional Version

There are many different types of cancer, which have different causes and risk factors. Also, individual people have different risks for developing different cancers. Therefore, no set of prevention strategies is effective in every person. However, some general strategies do reduce risk of cancer in many people.

Early detection of cancerous or precancerous growths can save lives. So it is important that people get recommended screening tests for cancer.

Lifestyle factors

Reducing the risk of certain cancers may be possible through dietary and other lifestyle changes. How much risk can be reduced depends on the specific cancer.

Dietary changes reduce the risk of some types of cancer:

  • Decreasing alcohol intake can reduce the risk of head and neck, liver, and esophageal cancer.

  • Decreasing fat intake appears to reduce the risk of breast and colon cancer.

  • Limiting the intake of processed meat and increasing the intake of whole grains and fruits and vegetables may decrease risk of some types of cancer.

The way meat is cooked may also increase the risk of cancer. Grilling, broiling, or frying meats creates certain chemicals that have been linked to colon cancer. Using other cooking methods reduces the formation of these chemicals and may reduce the risk of colon 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. People who quit smoking can also reduce their risk of cancer, and the risks decrease over time. Avoiding the use of smokeless tobacco (snuff or chew) decreases the risk of cancer of the mouth and tongue.

Being overweight or obese increases cancer risk, especially breast cancer, colon cancer, endometrial cancer, esophageal cancer, kidney cancer, and pancreatic cancer. People should try to maintain a healthy weight through both diet and exercise. Physical activity itself may reduce the risk of breast, endometrial, and prostate cancers.

Environmental factors

Carcinogens are substances that increase the risk of cancer. Some carcinogens, such as asbestos and benzene, may be present in the workplace, and workers in industries that use known carcinogens should take appropriate precautions to avoid or minimize exposure. Other carcinogens occur in the home or the environment. For example, radioactive elements that naturally occur in the earth decay into radioactive radon gas, which can collect inside the houses of people who live in certain areas. Exposure to radon increases the risk of lung cancer, especially in people who smoke.

Avoiding sun exposure (especially during the middle of the day) can reduce the risk of skin cancer. Covering exposed skin and using broad-spectrum sunscreen products with a sun protection factor (SPF) of at least 30 that protects against both ultraviolet A and ultraviolet B light also help reduce the risk of skin cancer.

Vaccines against cancer

Vaccines can prevent certain types of cancer that are caused by viruses. For example, certain strains of sexually transmitted human papillomavirus (HPV) cause cervical cancer, anal cancer, and some forms of head and neck cancer. Vaccination against HPV before the first sexual encounter can largely prevent many cases of these cancers.

As another example, infection with hepatitis B virus increases the risk of liver cancer. Vaccination against hepatitis B virus can help prevent liver cancer.

Other factors

Use of aspirin 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. Removing precancerous colon polyps helps prevent colorectal cancers.

Avoiding the use of hormone therapy (for example, estrogen and progesterone) for symptoms of menopause may decrease the risk of breast and endometrial cancers.

Additional Information of Prevention of Cancer

The following is an English-language resource that may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

Drugs Mentioned In This Article

Generic Name Select Brand Names
No US brand name
NOTE: This is the Consumer Version. DOCTORS: Click here for the Professional Version
Click here for the Professional Version
Others also read

Test your knowledge

Cancer Treatment Principles
Which of the following is the best description of palliative therapy in cancer treatment?
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID

Also of Interest

Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID