Nature vs. Nurture

What can I do?

There’s so much information about cancer out there! It can be overwhelming.

So we’re keeping this simple. Through the partnership between Stand Up To Cancer (SU2C) and American Airlines, we are providing you with solid information on how to reduce your risk of getting cancer.

First, a little background. Even though we talk about cancer of the lung or the breast or bladder, it’s actually a disease of DNA. It’s caused by glitches in genes, errors that make cells start growing and spreading out of control.

You may be born with some of these changes in genes, some occur over time, and some result from external influences such as exposure to sunlight or tobacco smoke. For many of these, you can take steps to lower your risk.

“The cancer research community agrees that more than 40 percent of cancer diagnoses and cancer deaths in the US are preventable,” says Ray DuBois, MD, PhD, dean of the college of medicine of the Medical University of South Carolina.

One report estimates that following prevention guidelines reduces the risk  of getting cancer by up more than 50% for many of the cancer types analyzed, . (1)

When the researchers grouped the related issues of excess body weight, alcohol intake, poor diet, and physical inactivity, they found this set of risks was responsible for a total of about 18% of cancer cases and 16% of deaths.

So it’s quite simple how you can reduce your cancer risk : Don’t smoke, eat right, and exercise.

Eat, Walk, Thrive

Diet, body weight, and physical activity affect your risk of cancer more than you might think. While there is no specific diet to reduce cancer risk, experts agree that it’s important to maintain a healthy body weight and avoid obesity.  Limit consumption of foods high in fats and/or added sugars and foods that are low in fiber, because they contribute to weight gain. Eat a variety of veggies, fruits, whole grain and beans because they pack fewer calories.  “It’s definitely a lot healthier,” says Dr. DuBois.

Being physically active and keeping lean, without being underweight, helps you avoid many cancers, including, colorectal, breast and pancreas. Thirty minutes of activity, like brisk walking, on most days of the week are recommended. If you enjoy the intensity of running, swimming or cycling, aim for at least 75 minutes a week spread over a few days.

Butt out

There’s no other way to say it: Quitting smoking can save your life. People who keep smoking die an average of 10 years earlier than those who have never smoked, according to one study. (2)  The American Cancer Society also advises don’t use e-cigarettes or smokeless tobacco, such as chewing tobacco. It’s not just lung cancer: smoking causes 17 other forms of cancer, including cancer in the bladder, kidney, stomach, throat and mouth,(3)  not to mention emphysema, heart disease and other problems. A study by the American Cancer Society found that nearly half of cancer deaths from 12 different cancers are attributable to smoking.  “If we can stop smoking, we’d have a drastic reduction in cancer,” says Daniel Von Hoff, MD, physician-in-chief at the Translational Genomics Research Institute and professor of medicine at the Mayo Clinic.

The good news? When you quit smoking, your risk starts falling. In 10 years, your risk of lung cancer goes down by 30 to 50 percent. (4)  If you quit before 45, you gain back nine of those ten lost years. Even if you’re in your 50s, quitting substantially cuts your risk of dying earlier than if you had never smoked.  (2)

SU2C and American Airlines can help you quit with resources that can make it a little bit easier, such as American’s Knock Out Nicotine program.

Experts recommend that heavy smokers or ex-smokers (a pack a day for 30 years), over the age of 55 consider getting yearly scans for lung cancer with low-dose CT to catch any problems early. (5)

The sun don’t shine

Tans, sunburns, tanning salons can cause serious issues for your skin. They can lead to skin cancer, including melanoma, which causes more than 7,000 deaths a year in the US. (6) Even people with dark skin are at risk.

Stay out of the sun or wear protective clothing, a hat, and sunglasses and repeatedly apply broad-spectrum sunscreen – The American Academy of Dermatology recommends that people of all skin toes use broad-spectrum (meaning both UVA and UVB) waterproof sunscreen rated SPF 30 or higher.

All in the family

For some people, cancer runs in the family, with genetic mutations passed down from one generation to another, so it’s essential to know your family’s history.  Says Dr. Von Hoff: “It could be lifesaving.”

Dr. Von Hoff recommends making a family tree, and writing down every case of cancer-especially in people who are young. “Know your family history, and tell your doc about it,” he says.

When you get down to it, reducing your risk of cancer is really pretty simple. “Number one is don’t smoke. Number two is stay active. Number three is know your family history,” says Dr. Von Hoff. “That’s prevention.”


Focus on food

Following the science of what to eat and what not to eat can be frustrating. Recommendations from experts change over time.

As far as cancer is concerned, here’s the straight talk: There are no magic foods that prevent cancer– not grapes, not pomegranates, not blueberries. Not green tea.

What can help prevent cancer is your overall diet. The most important thing is to maintain a healthy weight and avoid obesity. About 20 percent of all cancers are linked to being overweight or obesity.

To avoid obesity, experts suggest:

  • Limit consumption of foods high in fats and/or added sugars and foods that are low in fiber, because they contribute to weight gain. Instead select whole grains which help to promote healthy weight
  • Eat more of a variety of vegetables, fruits, – at least 5 servings a day.
  • Limit red meat and processed meats,processed meats include bacon, sausage, lunch meats, and hot dogs. (Researchers have found a strong link between processed meats and colorectal cancer, and a likely link between red meat and colorectal cancer.

The same goes for cancer survivors: There’s no one food or supplement that can keep you disease-free, but the overall pattern of how you eat can makes a difference.

What’s for dinner?

Eat foods that help you keep to a healthy weight-especially plants. The American Cancer Society recommends at least two and half cups of vegetables and fruits (or 5 servings) every day, which helps keep you lean, reducing cancer risk. Some evidence suggests that people who eat more vegetables have fewer cancers of the mouth, throat and digestive system.

Whole grains like whole wheat, oats and brown rice may reduce cancer risk, especially colorectal cancer. Because they’re high in fiber, you stay full longer, which helps stop weight gain.

Rather than red meat, try fish or poultry. Beans are a great high-protein, high-fiber option.

Scientific studies are currently testing dark green and orange vegetables, onions, garlic, soy, tomatoes, and bitter cruciferous vegetables like Brussels sprouts and cabbage to look for cancer-fighting benefits. None of them have been proven, but they’re all healthy options. So if you like them, dig in!

Maybe, maybe not

Although a drink now and then might be good for your heart, it slightly increases the risk of cancers in the mouth, throat, liver and breast. Experts say that if you drink, don’t drink much: No more than one a day for women, and two for men.

In the past, scientists thought that eating lots of fat causes cancer, but bigger and better studies show that probably isn’t true. However, fatty foods make it easy to gain weight-and excess weight is definitely linked to cancer.

No thanks, I’ll pass

Processed and smoked meats like sausage, bacon, hot dogs or ham, while delicious, increase the risk of cancer in the digestive system, perhaps because of the chemicals used to preserve them. Research suggests that eating 50 grams of processed meat every day (five pieces of bacon or two slices of smoked turkey or other lunch meat) increases your long-term risk of colorectal cancer by about 15 percent.

Pork, lamb, beef and other red meats may boost cancer risk if you eat them frequently. If you love red meat, go for lower-fat cuts (lean hamburger or get fancy with pork tenderloin or filet mignon!) and eat smaller portions, less often.

Sugar isn’t toxic, and there’s no proof it increases cancer. But sweets and sodas can have a lot of calories, so drinking or eating them makes it easy to gain weight.

Vitamins are supposed to be good for you … but large, well-run studies revealed a surprise: beta-carotene and Vitamin A supplements actually increase the risk of lung cancer among smokers, and Vitamin E slightly increases prostate cancer risk. Talk to your doctor about the vitamins and natural supplements you take. They can even interfere with how routinely prescribed medications work.

Physical Activity

Move it!

We just told you there is no magic bullet against cancer. Actually… that’s not exactly true. There is something that lowers your risk, prevents other diseases, and also makes you look better and feel younger…all at the same time: physical activity!

You’ve already heard the reasons why physical activity is so awesome: It gives you more energy, keeps your brain healthy, and helps you avoid everything from diabetes to heart disease to high blood pressure (in addition to making you look great).

But you probably didn’t know that being active also protects against breast and colon cancer, two of the most common types. It also might reduce pancreatic, endometrial and advanced prostate cancer.

We’re all in this together, and we can do it together, with the best knowledge from research and the science supported by SU2C, and the advice of your own doctor.

What do I have to do?

You don’t have to go to the gym every day. Walking, yard work and bicycling are all simple ways to get a bit more activity.

The Centers for Disease Control recommends adults spend at least two and a half hours every week doing moderate physical activity-something like fast walking, golfing or yoga. It’s not that much-30 minutes on most days, even in 10-minute chunks of time. The alternative is to turn up the dial to a higher intensity, jogging, swimming or playing basketball for a weekly total of at least 75 minutes. If you can get more in, go for it: 5 hours a week of moderate activity further reduces cancer risk.

If you’re not very active now, increasing your activity by any amount will help. Just taking longer walks or using the stairs instead of the elevator can start improving your health. You’ll benefit even if you start the habit as an adult.

What will I get out of it?

You’ll look and feel better! On the path to health and wellness that we’re walking together, this may be the best thing you can do for yourself. Plus:

  • Active women reduce their risk of breast cancer by 25 percent. They also lower the risk of endometrial cancer (cancer of the uterus).
  • Regular physical activity is linked to a lower risk of colorectal cancer.
  • Among smokers or ex-smokers, more active people have lower rates of lung cancer.
  • Active men lower their risk of prostate cancer-especially if they do vigorous exercise.

Physical activity might help you lose weight or keep weight off. But even if your weight stays the same, you will still reduce your risk of some cancers by reducing your body fat.

What if I’m being treated for cancer now, or I’m a survivor?

Cancer doctors used to think that physical activity might be too stressful for people in treatment or after treatment.

Research shows that’s not true. Moderate activity during treatment can help lower the risk of blood clots, prevent anxiety and depression, and make you feel a little bit better. At least 20 studies of people with breast, colorectal, prostate, and ovarian cancer suggest that physically active survivors reduce their chances of a recurrence and improve their rates of survival.

The thought of physical activity might be tough for survivors who already feel exhausted. But some research suggests that cancer survivors who are active actually feel less fatigue.

That’s smart: Two studies have found that people diagnosed with cancer who were active were less likely to have a recurrence, and lived longer. In other studies, women with breast cancer who were moderately active, like walking 3 to 5 hours a week, had better survival rates.

If you’ve had drugs or radiation that might damage the heart, lungs or bone, or cause numbness in hands and feet, check with your doctor before starting to be more active.

Weight Management

If you’re packing a few extra pounds, join the club: Two-thirds of the people in the United States are overweight or obese.

But even though it’s so common, it’s not good for you. The science says that those extra pounds add up to a higher risk of cancer.

Think of it as an opportunity, a new possibility, a way to move toward that destination of health. Keeping a healthy weight is the number-one thing you can do to lower your risk of cancer (aside from quitting smoking, if you smoke.)

Facts and stats

Between 14% and 20% of all cancer deaths in US adults 50 years of age or older are partly related to being overweight. Carrying excess weight is linked to fourteen different types of cancer. Another scary stat: A recent study including more than 73,000 women found that for every 10 years that a woman was overweight, she raised her risk of “obesity-related” cancers like endometrial or colon cancer by 7 percent. “There’s no question that obesity is a terrible risk factor,” says Dr. Von Hoff from Translational Genomics Research Institute, a division of City of Hope.

Being overweight especially affects endometrial cancer-cancer of the uterus. Overweight women have two to four times the risk of this cancer; the heavier the woman, the higher the risk. Being overweight raises your risk for kidney, pancreas, gallbladder, and esophageal cancer, and possibly for liver, cervical, ovarian, stomach and aggressive prostate cancer too.

So-called “apple-shaped” people who carry their extra weight around the waist are at higher risk of colorectal cancer, and that’s especially true for men. It also increases the risk of pancreatic and endometrial cancer, as well as breast cancer after menopause.

Why does weight matter?

Recent research suggests that excess body fat changes the way your immune system and hormones like insulin function. “The more weight gain you have, the more insulin resistance, the more inflammation,” says Dr. Von Hoff.

For example, excess fat cells increase the level of estrogen in women’s bodies after menopause. And obese post-menopausal women are at higher risk of breast cancer.

If you’re overweight now or carrying excess body fat, there’s good news: There is something you can do about it. This might be the best thing you can do for yourself-with some help from American Airlines and SU2C.

People who lose weight also reduce the levels of certain hormones that fuel cancer, so top scientists think that they also reduce their risk of cancer. Dr. Von Hoff offers a dramatic example: In people who rapidly lose weight following gastric bypass, deaths from cancer decline by 30 percent in just three years. (An online calculator can tell you whether you’re considered overweight.)

Even better is to keep your weight in the healthy range to begin with. These tips will steer you toward healthy, filling foods that help keep weight off. Avoid snacks and treats like chips, muffins, cookies, sweet sodas and alcoholic drinks, all of which deliver a lot of calories without delivering much nutrition. Some research suggests that tracking your daily eating habits with an app or just with pen and paper helps you maintain or lose weight.

Physical activity helps maintain your weight, and it also helps keep hormones like insulin responding correctly.

So does getting enough sleep. Being overly tired can make high-calorie foods like sweet or salty snacks more difficult to resist, and there’s some evidence that sleep deprivation changes your hormone responses in a way that makes it easier to put on pounds.

Think of it this way: It’s just one more very good reason to stay at a healthy weight.

Detection Screenings

The Life-savers

Catching cancer right at the beginning (“early detection”) often makes a huge difference. Early-stage cancers are sometimes small enough to be cured with surgery, without radiation or drugs. Even if that’s not possible, treatments are far more effective in the early stages. There’s simply less cancer there to kill.

The best example of the power of early detection is cervical cancer, which once was a major killer of young women. In the 1950s, women started getting Pap smears, which detect cells that might turn into cancer, so they can be removed. Deaths from cervical cancer in the US have plunged by 70%. “Cervical screening has been hugely effective,” says Ray DuBois, MD, PhD, dean of the college of medicine of the Medical University of South Carolina. “It’s almost eliminated cervical cancer.”

What’s amazing is that we could do something similar with colon cancer. Right now, it’s the second biggest cancer killer of men and women combined in the US. It starts with small growths that can be seen before they spread. Colonoscopies or sigmoidoscopies can find precancerous polyps and small cancers and snip them out so that they never become a major threat. “The doctor can see every inch of the colon from the inside,” says Dr. DuBois.

These screens have reduced deaths from colorectal cancer by about 25 percent, he says. When it’s caught early, in stage one or stage two, the 5-year survival is up to about 95 percent. “It’s proved to be very effective.” Experts think half of the 50,000 deaths each year from colon cancer could be prevented if everybody over 50 got screened.

It really works! But right now, just 61 percent of Americans are up to date on their screenings.

Going in for a cancer screening might seem frightening or unpleasant. But think about it this way: it’s a chance to take advantage of what we already know about cancer. It’s part of a vision of the future in which all cancer will be detectable right from the start, and preventable or treatable.

Screening and testing are different. Screens spot problems before they cause symptoms. But they may mistakenly suggest that cancer is there when it isn’t. For example, mostwomen who get all the recommended mammograms will have a false-positive at some point in their lives. So any positive result on a screen must be confirmed with a test.

The following recommendations come from the collective wisdom of hundreds of scientific studies, and committees of top researchers convened by groups like the National Cancer Institute.


Cervical cancer: Between age 21 and 30, women should get a Pap smear every three years. Between 30 and 65, get a Pap smear/HPV test combination every five years.

Breast cancer: Not everyone agrees on the details on this one. Experts agree that women over 55 who are at average risk (who don’t have a parent, child or sibling with breast cancer) should get mammograms every one to two years. But some experts say that women should start getting regular mammograms at age 40; others say not until 50. Talk to your doctor about what age may be right for you. Scientists now know that monthly breast self-exams aren’t very useful in catching cancer early. Instead, women should get to know their breasts and discuss changes like lumps, tenderness, discharge, or swelling with your doctor.


Prostate cancer: The prostate-specific antigen (PSA) test was once recommended for every man over 50, but experts are rethinking that. More research is underway, but for now, the best advice is that you discuss your options with your doctor when you turn 50. African-Americans who have a close male relative with prostate cancer should talk to their doctor earlier, by age 45.

In fact, Dr. DuBois says that 50 is a good time to talk about your overall cancer risk with your doctor. This is when it’s time to bust out that family chart, and mention any relatives who have died young of cancer, because that may be relevant to your own health. You may not want to bring it up-but you should.

“Let’s face it, it’s your body, your risk for disease. This is a chance to make sure you’re getting screened for everything you need to,” says Dr. DuBois. “If we can empower employees to take this on, it would have much more impact than anything else we could do.”


At age 50, you should begin screening for colon cancer. Option one: A colonoscopy every 10 years. Option two: A virtual colonoscopy, sigmoidoscopy or double-contrast barium enema every five years. Option three: One of a range of different fecal tests on yearly schedules. Talk to your doctor or read more about it.

Check your skin every month for anything suspicious. That goes double for fair-skinned people, but dark-skinned people can get skin cancer too. Take your clothes off, use a mirror (or ask someone you like to help!), and look for moles that are growing, are bigger than a pencil eraser, have ragged edges, are itchy, crusty or painful, or just look weird.

The Takeaway

Your own family history is the most important guide, says Dr. Von Hoff. But for people at average risk, other kinds of cancer screening-full-body CT scans, or blood tests for ovarian cancer-are not recommended.  “Intense screening is not the right idea,” says Dr. Von Hoff.


(1) Adherence to Diet and Physical Activity Cancer Prevention Guidelines and Cancer Outcomes: A Systematic Review Lindsay N. Kohler, David O. Garcia, Robin B. Harris, Eyal Oren, Denise J. Roe and Elizabeth T. Jacobs Cancer Epidemiol Biomarkers Prev July 1 2016 25 (7) 1018-1028; DOI:10.1158/1055-9965.EPI-16-0121

(2) 21st-Century Hazards of Smoking and Benefits of Cessation in the United States Prabhat Jha, M.D., Chinthanie Ramasundarahettige, M.Sc., Victoria Landsman, Ph.D., Brian Rostron, Ph.D., Michael Thun, M.D., Robert N. Anderson, Ph.D., Tim McAfee, M.D., and Richard Peto, F.R.S. N Engl J Med 2013; 368:341-350January 24, 2013DOI: 10.1056/NEJMsa1211128

“Smokers who stopped smoking at 45 to 54 years of age and those who stopped at 55 to 64 years of age (median, 49 and 59 years, respectively) gained about 6 and 4 years of life, respectively. Even cessation at the age of 45 to 54 years reduced the excess risk of death by about two thirds.”

(3) Arteaga CL, Adamson PC, Engelman JA, Foti M, Gaynor RB, Hilsenbeck SG, et al. AACR Cancer Progress Report 2014. Clin Cancer Res 2014;20: S1–S112.

(4) “After a person has quit smoking for 10 years, the risk of lung cancer decreases 30% to 50%.”

(5) U.S. Preventive Services Task Force.  (NCI doesn’t make recommendations.)

(6) Skin Cancer Foundation

(7) “The Skin Cancer Foundation considers SPFs of 15 or higher acceptable UVB protection for normal everyday activity, and SPFs of 30 or higher acceptable for extended or intense outdoor exposures.”