Can you prevent cancer?

We know more about keeping cancer in check now than at any time in history. The death rate for all cancers fell 26% in the United States between 1991 and 2015 because of advances in screening and treatment.

But wouldn’t it be great if we could stop cancer before it started?

Experts say up to half of cancers are preventable through healthy lifestyle choices. So what does that mean for you and your own risk for this disease? Can you stop yourself from getting cancer?

We talked to Ernest Hawk, M.D., MPH, vice president and division head for Cancer Prevention and Population Sciences at MD Anderson. He answered these key questions about how much control you have over your chances for getting cancer.

How do we know that up to 50 percent of cancers could be prevented?

Researchers have conducted many studies that tracked hundreds of thousands of people over about 15 years and it was clear that the people who followed a healthy lifestyle were less likely to get cancer. By healthy lifestyle we mean following the nine ways to reduce your cancer risk: Exercise, avoid tobacco, eat a healthy diet, look after your skin, get cancer prevention vaccines, maintain a healthy weight, eliminate or limit alcohol, get cancer screening exams and talk with your doctor about your family history.

The results of these studies show that if you can live this healthy lifestyle you are significantly less likely to get cancer. In other words, your mom was right. Eating healthy, being physically active and staying out of the sun at the peak of the day are all good for you. We're reinforcing the wisdom of the ages.

Why do some people still get cancer, even if they follow all the recommendations to reduce their risk?

About 10% of cancer cases are inherited – or genetic. That means the person was born with a factor that makes them more likely to get cancer.  On top of that, there are many things that we do not know. For example, twenty-five years ago, we didn’t know that second hand smoke is a toxin that causes cancer. There may be cancer-causing toxins out there today that we have not identified yet.

We certainly do not want people to feel like their cancer is their fault. Nothing you do will guarantee that you won’t get cancer. All we can say for sure is that you can significantly reduce your risk.

What about environmental toxins?

Identifying cancer-causing toxins is a big challenge. That’s because cancer takes a long time to develop, so it can be hard to associate someone’s diagnosis with one specific event or exposure.

It took many years to learn about diet, exercise, tobacco, sun damage, viruses and the other things we know will increase your risk for cancer. The best advice is to focus on the things that we do know. Do your best to live a healthy lifestyle and take advantage of the risk reduction options that are available to you right now.

How do cancer screening exams impact your cancer risk?

Cancer screening exams can dramatically reduce your risk of dying from cancer. This disease is easiest to treat if it is caught early and cancer screening is the best way to do that.

Breast cancer screening exams have reduced breast cancer deaths by 20%. Colon cancer screening has reduced deaths from this cancer by about 50%. Screening improvements are one of the big successes of the last 30 years, so make sure you know what screening exams are right for you.

Where is the study of cancer prevention going and what do you think the outcomes will be?

We are working hard to understand the very early stages of cancer development so that we can do more to stop the disease before it gets going.

The story of cervical cancer has shown us how powerful this can be. Cervical cancer used to be one of the most common cancers in the population. Then we developed the Pap test, which allows us to find and remove abnormal cells before they become cancer.

Now we have the HPV vaccine, which stops the virus that leads to these abnormal cells. And that vaccine can help prevent five other cancers as well. Those are amazing discoveries. We need to be able to do this for many other cancers as well.

What do you think is the most important thing for people to know about cancer prevention?

The most important thing is that prevention lies in the hands of each of us. You can use those nine key strategies in your life, and so can your family and friends.

It can be difficult, and I know because ideally I need to lose a bit of weight myself. But everyone should at least try to live a healthy lifestyle because we know that we can reduce the risk of this disease. And we didn’t know that 25 years ago.