The American Cancer Society has updated its guideline on diet and physical activity for cancer prevention. Staying at a healthy weight, staying active throughout life, following a healthy eating pattern, and avoiding or limiting alcohol may greatly reduce a person's lifetime risk of developing or dying from cancer. At least 18% of all cancer cases in the US are related to a combination of these factors. These lifestyle habits are the most important behaviors after not smoking that people can control and change to help lower their cancer risk.

The updated guideline reflects the latest evidence published since the last update in 2012. It appears in the American Cancer Society’s peer-reviewed journal, CA: A Cancer Journal for Clinicians.

Diet and physical activity recommendations

Changes to the guideline include recommendations for getting more physical activity, eating less (or no) processed and red meat, and avoiding alcohol or drinking less. It says:

• Get to and stay at a healthy body weight throughout life. If you’re overweight or obese, losing even a few pounds can lower your risk for some types of cancer.
• Adults should get 150-300 minutes of moderate-intensity physical activity per week, or 75-150 minutes of vigorous-intensity physical activity, or a combination. Getting 300 minutes or even more will give you the most health benefits.
• Children and teens should get at least 1 hour of moderate or vigorous intensity activity each day.
• Spend less time sitting or lying down. This includes time looking at your phone, tablet, computer, or TV.
• Eat a colorful variety of vegetables and fruits, and plenty of whole grains and brown rice.
• Avoid or limit eating red meats such as beef, pork, and lamb and processed meats such as bacon, sausage, deli meats, and hot dogs.
• Avoid or limit sugar-sweetened beverages, highly processed foods, and refined grain products.
• It is best not to drink alcohol. But if you do, women should have no more than 1 drink per day and men should have no more than 2. A drink is 12 ounces of regular beer, 5 ounces of wine, or 1.5 ounces of 80-proof distilled spirits.

According to Laura Makaroff, DO, American Cancer Society senior vice president, Prevention and Early Detection, the guideline is based on current science that shows that how you eat, rather than specific foods or nutrients, is important in reducing the risk of cancer and boosting overall health.

“There is no one food or even food group that is adequate to achieve a significant reduction in cancer risk,” Makaroff said. People should eat whole foods, not individual nutrients, she said, because evidence continues to suggest that healthy dietary patterns are associated with reduced risk for cancer, especially colorectal and breast cancers.

Community action is key

Making healthy eating and exercise choices can be a challenge for many people. Social, economic, and cultural factors all play into the way people eat and get physical activity, and how easy or hard it is to make changes. Public, private, and community organizations should work together to increase access to affordable, healthy foods and provide safe, enjoyable and accessible opportunities for physical activity.

Any change you try to make for a healthier lifestyle is easier when you live, work, play, or go to school in a community that supports healthy behaviors. Look for ways to make your community a healthier place to live:

• Ask for healthier meal and snack choices at school or work.
• Support stores and restaurants that sell or serve healthy options.
• Speak up at city council and other community meetings about the need for sidewalks, bike lanes, parks, and playgrounds.

FAQs

The updated guideline also includes answers to questions that commonly arise within the general public, including information on genetically modified crops, gluten-free diets, juicing/cleanses, and more.

• Genetically modified crops are made by adding genes to plants to give them desired qualities such as being resistant to pests or having a better flavor. There is no evidence at this time that foods made with these crops are harmful to health, or that they affect cancer risk.
• Gluten is a protein in wheat, rye, and barley that is safe for most people. People with celiac disease should not eat gluten. For people without celiac disease, there is no evidence linking a gluten-free diet with a lower risk of cancer. There are many studies linking whole grains, including those with gluten, with a lower risk of colon cancer.
• There is no scientific evidence to support claims that drinking only juices for one or more days (a “juice cleanse”) reduces cancer risk or provides other health benefits. A diet limited to juice may lack some important nutrients and in some cases may even lead to health problems.