What are the Risk Factors of Cancer?

There are several risk factors for cancer and many of them are preventable. You should be very particular about avoiding the preventable causes.

Dr Poonam Sachdev
CancerWritten by: Dr Poonam SachdevPublished at: Aug 16, 2011Updated at: Mar 10, 2014
What are the Risk Factors of Cancer?

Cancer results due to uncontrollable growth of cells which do not follow the orderly path of growth, division, and death. It is difficult for health experts to explain why one person develops cancer and another does not.

There are certain risk factors that increase the chance that a person will develop cancer. Many of these risk factors can be avoided, but family history and genetic factors are unavoidable. Over time, the factors act together to cause normal cells to become cancerous.


cancer risk factors


The risk factors for cancer; some of which are preventable, are as follows.



Most cancers occur in older people. The risk of developing cancer increases with age probably due to prolonged exposure to carcinogens and the weakening of the body’s immune system. Some cancers occur in children (Wilms' tumour, retinoblastoma, and neuroblastoma) probably due to mutations that are inherited or that occur during foetal development.



The risk of cancer is higher in people who have a family history of cancer. However, just because you have a family history of cancer, does not mean you will definitely develop cancer. The risk may be increased due to a single altered gene or due to several genes interacting together. The presence of an extra or abnormal chromosome for example, increases the risk of cancer in Down syndrome (these people have three instead of the usual two copies of chromosome 21). The risk of developing acute leukaemia is 12 to 20 times higher in a person with Down syndrome.


Physical Activity

Exercising for about 30 minutes on most days of a week can significantly reduce the risk of cancer. You can practice any form of such as yoga, aerobics, walking and running. Being physically active not only helps to prevent diseases such as hypertension and diabetes, but it reduces the chances of becoming obese. Obesity is known to be a major cause for many cancers and being physically active can reduce your risk of developing prostate, colon, breast, endometrial and lung cancer.


Environmental Factors

Some environmental factors increase the risk of developing cancer. Exposure to asbestos (a group of minerals found in housing and industrial building materials) can cause lung cancer, and exposure to benzene (a chemical found in gasoline, smoking, and pollution) increases the risk of blood cancer.



Smoking is a major risk factor for the development of lung cancer and deaths due to it. Besides lung cancer smoking can also cause kidney, pancreatic, cervical, and stomach cancers and acute myeloid leukaemia. Quitting smoking can decrease your risk of cancer.


cancer risk smoking



The prevalence of certain cancers has increased in the past few decades and changes in diet have been implicated for it. Diets high in fat increase the risk of colon, breast, and possibly prostate cancer. Eating processed meat increases the risk of colon cancer and diets rich in smoked or barbecued meats increases the risk of developing stomach cancer.



Infection with certain viruses is known to cause cancer in humans. Cervical cancer in women can be caused due to infection with human papillomavirus (HPV, which causes genital warts) and infection with Hepatitis B virus or hepatitis C virus can cause liver cancer. Several other infections are known to increase the risk of developing cancer. For example an infection with Epstein-Barr virus can cause Burkitt's lymphoma (a type of cancer) in Africa and cancers of the nose and pharynx in China. Similarly infection with Schistosoma haematobium may lead to cancer of the bladder.


Sun Exposure

Exposure to the UV rays of the sun increases the risk of developing skin cancer especially in fair skinned people. The risk of skin cancer can be reduced by wearing sunscreen when you go outdoors and avoiding excessive exposure to the harsh rays of the sun.


If you suspect that you may be at risk for cancer, discuss this concern with your doctor. Ask them about a schedule for checkups and what you can do to reduce your risk.


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