Avoiding cancer risk factors such as smoking, being overweight, and lack of exercise may help prevent certain cancers. Increasing protective factors such as quitting smoking, eating a healthy diet, and exercising may also help prevent some cancers. Talk to your doctor or other health care professional about how you might lower your risk of cancer.
Having a parent, brother, sister, or child with colorectal cancer doubles a person's risk of colorectal cancer.
Cigarette smoking is linked to an increased risk of colorectal cancer and death from colorectal cancer.
Smoking cigarettes is also linked to an increased risk of forming colorectal adenomas. Cigarette smokers who have had surgery to remove colorectal adenomas are at an increased risk for the adenomas to recur (come back).
Obesity is linked to an increased risk of colorectal cancer and death from colorectal cancer.
A lifestyle that includes regular physical activity is linked to a decreased risk of colorectal cancer.
Taking aspirin every day for at least 5 years decreases the risk of colorectal cancer and the risk of death from colorectal cancer.
Studies have shown that hormone replacement therapy (HRT) that includes both estrogen and progesterone lowers the risk of colon cancer in postmenopausal women. HRT with estrogen alone does not lower the risk. However, hormone use increases the risk of breast cancer, heart disease, and blood clots.
The use of hormone replacement therapy that includes both estrogen and progesterone has not been shown to lower the risk of rectal cancer.
Most colorectal polyps are adenomas, which may develop into cancer. Removing colorectal polyps that are larger than 1 centimeter (cm) may lower the risk of colorectal cancer. It is not known if removing smaller polyps lowers the risk of colorectal cancer.
Studies have shown that taking the nonsteroidal anti-inflammatory drug celecoxib reduces the risk of colorectal adenomas (benign tumors) coming back after they have been removed. It is not clear if this results in a lower risk of cancerous tumors in the colon and rectum. Taking celecoxib also has been shown to reduce the number of polyps that form in the colon and rectum of patients with familial adenomatous polyposis (FAP).
The possible harms of NSAIDs include:
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Cancer prevention clinical trials are used to study ways to lower the risk of developing certain types of cancer. Some cancer prevention trials are conducted with healthy people who have not had cancer but who have an increased risk for cancer. Other prevention trials are conducted with people who have had cancer and are trying to prevent another cancer of the same type or to lower their chance of developing a new type of cancer. Other trials are done with healthy volunteers who are not known to have any risk factors for cancer.
The purpose of some cancer prevention clinical trials is to find out whether actions people take can prevent cancer. These may include exercising more or quitting smoking or taking certain medicines, vitamins, minerals, or food supplements.
Clinical trials are taking place in many parts of the country. Information about clinical trials can be found in the