Cancer Prevention and Healthy Living

Last Updated: November 18, 2019

Not all types of cancer can be prevented. However, research shows that lifestyle factors such as nutritional choices, regular exercise, and reducing stress can lower a person’s risk of developing certain types of cancer. Medical oncologist Dr. Mark A. O’Rourke discusses why these factors are important in lowering cancer risk. 

More Information

Prevention and Healthy Living

Understanding Cancer Risk

Food and Cancer Risk

Physical Activity and Cancer Risk

Resources to Help You Quit Smoking

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Cancer Prevention and Healthy Living

Voiceover: While it’s not possible to prevent all cancer, research has shown that there are ways to reduce your risk of getting cancer through things you do, and things you can avoid doing, in your everyday life.

Mark A. O’Rourke; Medical Oncologist; Member, American Society of Clinical Oncology:  When we think of cancer risk, that refers to things that can cause us to get cancer. When we think of cancer prevention, that refers to things we can do to reduce our risk of cancer.

There are some things that we have control over and some that we don't. I want to talk about the things that we have control over in terms of cancer risk factors. These include what are called lifestyle factors. It refers to smoking and diet and exercise.

Voiceover: Smoking is one of the leading causes of several types of cancer and quitting smoking is one way to significantly reduce your cancer risk.

Dr. Mark O’Rourke: I recognize in my practice that quitting smoking is the hardest thing that people ever do and, all too often, we dismiss that and say you just have to have more willpower.

The good news is that there are programs and people who can help with this. And if you want to quit smoking, you can connect with a healthcare provider who will help you do that .

Voiceover: Maintaining a healthy diet is also an important way you can reduce your risk of developing certain types of cancer. And that may not be as complicated as you think.

Dr. Mark O’Rourke: In terms of cancer prevention, diet is very important. I talk to a lot of people and there’s confusion about what diet is the best to prevent cancer. But we can simplify this to say five servings of fruits and vegetables per day is the best way to reduce your cancer risk.

This is because fruits and vegetables contain what are called phytochemicals and these are the chemicals that help the body and help the immune system resist cancer. Some people read about supplements and think they can get their phytochemicals through supplements, but it turns out that they are more effective if they come in the course of fruits and vegetables in a normal diet. So our message is, let your kitchen be your medicine cabinet and work on those five servings a day.

Voiceover: Another lifestyle factor that can cut your risk of developing cancer is regular physical activity.

Dr. Mark O’Rourke: What we’re talking about is a conscious effort to exercise 15 or 30 minutes a day where you’re walking at a brisk pace or doing some form of moderate exercise. One way to know whether it’s moderate exercise or not, you want to walk at a pace where you can carry on a conversation with someone, but you wouldn’t have enough breath to sing a song.

The experts have found that 30 minutes a day five days a week for 150 minutes a week of exercise has been helpful in reducing the risk of cancer. So my message would be to find a way to work into your routine getting that 150 minutes a week.

It’s different for different people, but I encourage all of my patients and myself and my family and friends to set aside that time and make it a priority as if it were a medical prescription in and of itself. If exercise were a drug, it would be a billion dollar blockbuster, but is something we can do for free if we can just take the time to do it.

Voiceover: Trying to control the amount of stress in your life is also important when it comes to lowering your risk of developing cancer. Talk with your doctor about stress reduction programs that may be right for you.

Dr. Mark O’Rourke: Stress reduction refers to those things that we can do in our lifestyle that reduce the amount of inflammation in our body. And the scientists who have shown that you can measure cortisol and other inflammatory chemicals in the body and these contribute not only to the risk of cancer, but also heart disease, diabetes and other illnesses.

Some people have found meditation to be helpful, others find yoga to be helpful. What we’ve learned, however, is that diet and exercise are not just nice things to do, but they are key to improving our stress, key to reducing inflammation and key to helping us reduce our risk factors for cancer.

Exercise, Eat Healthy, Reduce Stress

Dr. Mark O’Rourke: So if we can exercise regularly, eat healthy and then do things like meditation and biofeedback to reduce our stress, we can really help ourselves.


Voiceover: To learn more how a healthy lifestyle can reduce your risk of developing certain cancers, visit Cancer.Net/Prevention.

Dr. Mark O’Rourke: There’s one resource that I can recommend and it is This is the resource provided by the American Society of Clinical Oncology. It is written for the public to understand. It describes different kinds of cancer, but it also describes diet, exercise and lifestyle things that we can do to control cancer.

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