Diet, Activity Recommendations May Reduce the Risk of Cancer, Experts Say Looking for ways to cut your risk of developing cancer? Here's a list of 10 diet and activity recommendations highlighted this week in Chicago at the annual meeting of the American Dietetic Association (ADA).
- Be as lean as possible without becoming underweight.
- Be physically active for at least 30 minutes every day.
- Avoid sugary drinks, and limit consumption of high-calorie foods, especially those low in fiber and rich in fat or added sugar.
- Eat more of a variety of vegetables, fruits, whole grains, and legumes (such as beans).
- Limit consumption of red meats (including beef, pork, and lamb) and avoid processed meats.
- If you drink alcohol, limit your daily intake to two drinks for men and one drink for women.
- Limit consumption of salty foods and food processed with salt (sodium).
- Don't use supplements to try to protect against cancer.
- It's best for mothers to exclusively breastfeed their babies for up to six months and then add other liquids and foods.
- After treatment, cancer survivors should follow the recommendations for cancer prevention.
At the ADA meeting, experts provided practical tips for following those recommendations, which were issued last year by the nonprofit American Institute for Cancer Research and its sister organization, the World Cancer Research Fund International.
Why These Cancer Recommendations?
Walter Willett, MD, DrPH, an epidemiology professor who leads the nutrition department the Harvard School of Public Health, was on the international team of scientists that wrote the recommendations.
At the ADA meeting, Willett said the first recommendation -- to be as lean as possible within the healthy weight range -- is "the most important, by far."
But there is one recommendation that Willett says may be a "mistake" -- the one about not taking supplements. Vitamin D supplements may lower risk of colorectal cancer and perhaps other cancers, notes Willett. He predicts that that recommendation will be a top priority for review.
How to Follow the Recommendations
Karen Collins, MS, RD, CDN, is the nutritional advisor for the American Institute for Cancer Research. She reviewed the recommendations before they were issued last year, and she joined Willett in talking to ADA members.
Collins provides these tips for each of the recommendations:
- Be as lean as possible without becoming underweight: Don't just look at the scale; check your waist measurement as a crude measurement of your abdominal fat, Collins says. She recommends that men's waists be no larger than 37 inches and women's waists be 31.5 inches or less.
- Be physically active for at least 30 minutes every day: You can break that into 10- to 15-minute blocks, and even more activity may be better, notes Collins.
- Avoid sugary drinks and limit consumption of energy-dense foods: It's not that those foods directly cause cancer, but they could blow your calorie budget if you often overindulge, notes Collins, who suggests filling up on fruits, vegetables, and whole grains.
- Eat more of a variety of vegetables, fruits, whole grains, and legumes such as beans: Go for a variety of colors (like deep greens of spinach, deep blues of blueberries, whites of onions and garlic, and so on). Most Americans, says Collins, are stuck in a rut of eating the same three vegetables over and over.
- If consumed at all, limit alcoholic drinks to two for men and one for women per day: Watch your portion size; drinks are often poured liberally, notes Collins. Willett adds that the pros and cons of moderate drinking is something that women may particularly need to consider, weighing the heart benefits and increased breast cancer risk from drinking.
- Limit red meats (beef, pork, lamb) and avoid processed meats: Limit red meats to 18 ounces per week, says Collins, who suggests using chicken, seafood, or legumes in place of red meat. Collins isn't saying to never eat red meat, just do so in moderation.
- Limit consumption of salty foods and foods processed with sodium: Don't go over 2,400 milligrams per day, and use herbs and spices instead, says Collins. She adds that processed foods account for most sodium intake nowadays -- not salt you add when cooking or eating.
- Don't use supplements to protect against cancer: It's not that supplements are bad -- they may be "valuable" apart from cancer prevention, but there isn't evidence that they protect against cancer, except for vitamin D, says Collins.
- It's best for mothers to breastfeed babies exclusively for up to six months and then add other foods and liquids: Hospitals could encourage this more, Collins says.
- After treatment, cancer survivors should follow the recommendations for cancer prevention. Survivors include people undergoing cancer treatment, as well as people who have finished their cancer treatment.
Overwhelmed? Collins boiled the 10 recommendations down to these three:
- Choose mostly plant foods. Limit red meat and avoid processed meat.
- Be physically active every day in any way for 30 minutes or more.
- Aim to be a healthy weight throughout life.
Keep in mind that these tips are about reducing -- but not eliminating -- cancer risk. Many factors, including genes and environmental factors, affect cancer risk; diet and exercise aren't the whole story, but they're within your power to change.
Some more tips:
You've probably heard conflicting reports about cancer prevention. Sometimes the specific cancer-prevention tip recommended in one study or news report is advised against in another. If you're concerned about cancer prevention, take comfort in the fact that small changes in your daily life can make a big difference. Consider seven real-life cancer prevention tips.
1. Don't use tobacco
Using any type of tobacco puts you on a collision course with cancer. Smoking has been linked to various types of cancer — including cancer of the lung, bladder, cervix and kidney — and chewing tobacco has been linked to cancer of the oral cavity and pancreas. Even if you don't use tobacco, exposure to secondhand smoke may increase your risk of lung cancer.
Avoiding tobacco — or deciding to stop using it — is one of the most important health decisions you can make. It's also an important part of cancer prevention. If you need help quitting tobacco, ask your doctor about stop-smoking products and other strategies for quitting.
2. Eat a healthy diet
Although making healthy selections at the grocery store and at mealtime can't guarantee cancer prevention, it may help reduce your risk. Consider these guidelines:
- Eat plenty of fruits and vegetables. Base your diet on fruits, vegetables and other foods from plant sources — such as whole grains and beans.
- Limit fat. Eat lighter and leaner by choosing fewer high-fat foods, particularly those from animal sources. High-fat diets tend to be higher in calories and may increase the risk of overweight or obesity — which can, in turn, increase cancer risk.
- If you choose to drink alcohol, do so only in moderation. The risk of various types of cancer — including cancer of the breast, colon, lung, kidney and liver — increases with the amount of alcohol you drink and the length of time you've been drinking regularly.
3. Maintain a healthy weight and include physical activity in your daily routine
Maintaining a healthy weight may lower the risk of various types of cancer, including cancer of the breast, prostate, lung, colon and kidney. Physical activity counts, too. In addition to helping you control your weight, physical activity on its own may lower the risk of breast cancer and colon cancer.
As a general goal, include at least 30 minutes of physical activity in your daily routine — and if you can do more, even better. Try a fitness class, rediscover a favorite sport or meet a friend for daily brisk walks.
4. Protect yourself from the sun
Skin cancer is one of the most common kinds of cancer — and one of the most preventable. Try these tips:
- Avoid midday sun. Stay out of the sun between 10 a.m. and 4 p.m., when the sun's rays are strongest.
- Stay in the shade. When you're outdoors, stay in the shade as much as possible. Sunglasses and a broad-rimmed hat help, too.
- Cover exposed areas. Wear tightly woven, loosefitting clothing that covers as much of your skin as possible. Opt for bright or dark colors, which reflect more ultraviolet radiation than pastels or bleached cotton.
- Don't skimp on sunscreen. Use generous amounts of sunscreen when you're outdoors, and reapply often.
- Avoid tanning beds and sunlamps. These are just as damaging as natural sunlight.
5. Get immunized
Cancer prevention includes protection from certain viral infections. Talk to your doctor about immunization against:
- Hepatitis B. Hepatitis B can increase the risk of developing liver cancer. The hepatitis B vaccine is routinely given to infants. It's also recommended for certain high-risk adults — such as adults who are sexually active but not in a mutually monogamous relationship, men who have sex with men, and health care or public safety workers who might be exposed to infected blood or body fluids.
- Human papillomavirus (HPV). HPV is a sexually transmitted virus that can lead to cervical cancer. The HPV vaccine is available to both men and women age 26 or younger who didn't have the vaccine as an adolescent.
6. Avoid risky behaviors
Another effective cancer prevention tactic is to avoid risky behaviors that can lead to infections that, in turn, may increase the risk of cancer. For example:
- Practice safe sex. Limit your number of sexual partners, and use a condom when you do have sex. The more sexual partners you have in your lifetime, the more likely you are to contract a sexually transmitted infection — such as HIV or HPV. People who have HIV or AIDS have a higher risk of cancer of the anus, cervix, lung and immune system. HPV is most often associated with cervical cancer, but it may also increase the risk of cancer of the anus, penis, throat, vulva and vagina.
- Don't share needles. Sharing needles with an infected drug user can lead to HIV, as well as hepatitis B and hepatitis C — which can increase the risk of liver cancer. If you're concerned about drug abuse or addiction, seek professional help.
7. Take early detection seriously
Regular self-exams and professional screening for various types of cancers — such as cancer of the skin, colon, prostate, cervix and breast — can increase your chances of discovering cancer early, when treatment is most likely to be successful. Ask your doctor about the best cancer screening schedule for you.
Take cancer prevention into your own hands, starting today. The rewards will last a lifetime.