Hesperian Health Guides

Much Cancer Can Be Prevented

Many different things may cause cancer, and usually there is no way to know if one particular thing was the cause of a person’s cancer except for:

Most other cancers seem to come from a combination of exposures to certain harmful things.

While we cannot prevent all cancers, we can lower our risk of getting cancer by limiting the things that make cancers more common.

a man and a woman smoking with a small child on the woman's lap.

Avoid smoke and smoking

  • Tobacco smoking is one of the main causes of cancer around the world. Smoking causes lung cancer and also cancers of the colon, bladder, and neck. It leads to heart attacks, strokes, lung infections, and ulcers, and when pregnant women smoke or breathe other’s cigarette smoke, their babies are more likely to be sick or dangerously small. Stopping smoking makes cancer less likely for the smoker, no matter how old you are when you quit, and protects family and friends too. See Drugs, Alcohol, and Tobacco (in development) for more on how to stop smoking.
  • Indoor cooking fires increase the chances of cancer and lung diseases. Building a no-smoke or low-smoke cook stove and venting smoke outside reduces the possibility of cancer for the whole family.
  • Pollution from factories, cars, and trucks causes cancer. When people demand it and laws require it, they can be made to produce less smoke and less cancer.
  • Work in a smoky environment is dangerous. If you and your co-workers can get your boss to improve ventilation, or at least provide you with filtered masks (respirators), your health will be better.
a man drinking alcohol from a bottle.

Drink less alcohol

Drinking more than a glass or two of alcohol a day makes several cancers more likely. Breast cancer, liver cancer, stomach and intestinal cancer, and mouth and throat cancer all may be related to drinking alcohol. Drinking less can also leave more money for food and other family needs. See Drugs, Alcohol, and Tobacco (in development) for more on how to stop drinking.

Avoid and treat infections

  • H. pylori, the bacteria that causes stomach ulcers, can lead to stomach cancer if it is not treated. If you have a stomach ulcer that keeps coming back, it can be treated with medicines as described in Belly Pain, Diarrhea and Worms.
  • Hepatitis B and C can lead to liver cancer. There is a vaccine for hepatitis B, and both hepatitis B and C can be prevented by using condoms during sex and not reusing needles for injections. See more on hepatitis.
  • HPV (human papilloma virus, a sexually transmitted infection) causes cervical cancer in women and several other cancers in both men and women. There is a vaccine to protect against HPV.
  • HIV makes certain cancers more common, especially Kaposi’s sarcoma, non-Hodgkin’s lymphoma, and cervical cancer. Prevent HIV by using condoms during sex and not reusing needles.

Good food makes good health

Eating habits can contribute to or protect against cancer. Eating whole grains, and fresh vegetables and fruits every day helps protect you from many cancers and other illnesses. See how to eat well even when you have little money. Storing grains and beans in a ventilated space prevents spoilage by a mold that is one cause of liver cancer.

Access to healthcare

When people have access to good quality healthcare, they have better health and more cancer is prevented. Access to healthcare also helps to find cancers early which makes treatment more successful.

Avoid exposure to chemicals

Thousands of chemicals are made and used in industry and agriculture, and then released into the air we breathe, the water we drink, and the food we eat. Some of these chemicals are harmful to our health, including some which cause or contribute to cancer. Unfortunately there are no laws that say a chemical must be proven to be safe before it can be used, so we often find out too late about the dangers of chemicals. The increased use of chemicals around the world is one reason rates of cancer are increasing. Important ways to protect against chemicals and cancer include:

  • Assume a chemical is dangerous until it is proven safe.
  • Avoid using pesticides and chemical cleaners, or reusing any containers chemicals may have been stored in.
  • Don’t burn plastics or other trash (this releases toxic fumes into the air we breathe).
  • If you cannot convince your boss to change to safer chemicals in your workplace, try not to breathe or touch them. Wear gloves, a face mask, and protective clothing, and wash your hands often so chemicals do not get into your food or your mouth.
  • Insist that governments make sure power plants and factories handle their waste safely and do not cause pollution. For more on organizing your community against chemical exposure, see A Community Guide to Environmental Health, also available from Hesperian.
an illustration of the path of pollution entering a nursing woman's body. Industrial pollution finds its way into our bodies. Stopping pollution will lead to less cancer.

When we value human lives more than profits, cancer will be reduced.

This page was updated:25 Nov 2019