- A new study confirms that adhering to the American Institute for Cancer Research’s Cancer Prevention Recommendations reduces the risk of breast, colorectal and lung cancers.
- Making lifestyle changes so your habits align with the recommendations can help reduce cancer risk. Even making a few small changes can help.
- Future studies will look at how adhering to the recommendations helps with cancer survival, because one of the recommendations is to follow the Cancer Prevention Recommendations after a cancer diagnosis, too.
Each of the 10 AICR Cancer Prevention Recommendations is based on strong evidence, so you can expect that following them will lower your risk of cancer. Now, a new analysis has been published in the journal Cancer, which confirms the many benefits of following the AICR Recommendations.
If you have ever wondered whether the strategies in the Recommendations are enough to reduce cancer risk, or whether benefits increase as you follow more of the Recommendations, you will learn those answers here.
The new publication combines the results of 18 different observational studies. It concludes that lifestyles that align more closely with the AICR Recommendations do, indeed, lower the risk of breast, colorectal and lung cancers—three of today’s most common cancers. And each step closer to meeting the Recommendations helps.
For more background and insights on this important analysis, I spoke to Fiona Malcomson, BSc (Hons), MRes, PhD, a lecturer in nutrition at Newcastle University in the UK and lead author of this paper.
Healthy Lifestyle Choices Help Prevent Cancer
When asked what she considers the biggest take-away from this research, Malcomson says, “I think the most important finding is the reduction in risk of specific cancers. For each 1-point increase in adherence score (adhering to the Recommendations), we found:
- 11 percent lower risk of breast cancer
- 12 percent lower risk of colorectal cancer
- 8 percent lower risk of lung cancer
The scoring system used for this analysis awards points based on how someone’s diet and lifestyle align with the AICR Cancer Prevention Recommendations. Scores can range from 0 to 7 or 8, depending on whether a score for breastfeeding is included. Details on the scoring system can be found here.
Adhering to Recommendations Is Helpful
Malcomson and her colleagues found that a single-point improvement in score significantly reduced cancer risk. In some cases, even improving by half a point can make a difference, since small changes can add up.
Meeting any one additional recommendation produces the one-point increase in score that’s associated with the reduced cancer risk. Here are some examples of a one-point increase:
- You usually get less than an hour of moderate physical activity per week, but make a change to get 30 minutes of activity per day.
- You eat red meat most days and processed meat several times a week, but make a change to cut down to a moderate portion of red meat three or four times a week and processed meat just a couple of times a month.
- You typically drink a sugar-sweetened soft drink every day, but switch to water or unsweetened iced tea more often.
The same score increase could come from making a couple of smaller changes—moving from not meeting a recommendation to at least coming closer (partially meeting), or from partially meeting a recommendation to fully meeting it.
- If your alcohol consumption is higher than the national guidelines (more than 2 drinks per day for men or more than 1 drink per day for women) and you cut down to having an alcoholic drink just a few days a week, that earns half a point.
- If you change from only a couple of small servings of fruits and vegetables a day to getting at least five a day, that earns another half a point.
Together, these two smaller changes add up to a 1-point increase in your score.
Results of this analysis are consistent with overall research, notes Malcomson. Studies have identified multiple aspects of diet, physical activity and weight that are linked with risk of breast, colorectal and lung cancers.
What About Prostate Cancer?
Recommendation adherence scores were not associated with risk of prostate cancer in this analysis. Malcomson notes that she and her colleagues were only able to find two studies that examined prostate cancer and alignment of lifestyle with the Recommendations.
Even so, Malcomson notes that the AICR/WCRF Third Expert Report concluded that strong evidence for lifestyle choices and prostate cancer risk was related only to increased risk of advanced, high-grade or fatal prostate cancers with excess body fatness. Other than that, evidence isn’t yet clear about diet and other lifestyle choices in relation to prostate cancer risk.
This analysis adds to research suggesting that “if there’s a relationship, it’s going to be much more specific within aspects of prostate cancer, rather than just risk of prostate cancer overall.”
Implications for Future Research on Reducing Cancer Risk
The goal of analyzing whether following the recommendations works to lower the risk of cancer or other chronic diseases is nothing new. Many studies have tried to answer such questions.
But it’s not as easy as you might expect to define and categorize how closely people come to meeting the recommendations. And since different researchers created different ways to score lifestyle alignment with the recommendations, this had previously created obstacles to comparing results from different studies to get a cohesive picture.
A major step forward came with the work of a team of scientists from the National Institutes of Health National Cancer Institute, WCRF and AICR, which created a standardized scoring system (the 2018 WCRF/AICR Score). As this standardized scoring gets used in more studies, researchers will be able to synthesize results for stronger answers. Plus, larger numbers of people in combined studies will make it possible to look at less common cancers and different sub-types of cancer.
To study diseases like cancer that develop over many years, researchers need to rely on data about diet and lifestyle collected early in a study. Questionnaires traditionally used in large studies don’t always provide information needed to fully assess alignment with cancer prevention recommendations.
- Physical activity can occur in many forms and spread throughout the day, making it difficult to capture in these questionnaires.
- Ultra-processed food consumption is challenging to assess accurately.
- Waist circumference adds valuable data to identify differences in body fat, since weight alone (or body mass index [BMI]) can’t capture body composition. But in observational studies, waist circumference is trickier to collect so some studies just focus on BMI.
The upside? Malcomson explains, “This analysis highlights that to increase the ability to reproduce and compare across studies, researchers need to try to apply a standardized approach, or at least detail any changes made to scoring when investigating associations with cancer incidence.”
Next Steps in Research on Lifestyle and Cancer Risk
Learnings from one study provides a foundation for research to answer other questions. When asked about the next steps to build on this analysis, Malcomson explained, “This analysis was the first step we needed for an analysis in the UK Biobank cohort. In that study, which is supported with funds from WCRF, we’re using the standardized recommendations adherence score to look at risk of 14 lifestyle-related cancers as well as risk of all cancers combined.”
Analysis is already underway, and Malcomson reports, “We’re also going to look at cancer survival, because one of the recommendations is to follow the Cancer Prevention Recommendations after a cancer diagnosis (if you can, and if approved by your personal health-care provider). AICR and WCRF are already working on the evidence base for associations between lifestyle and cancer survival. So, hopefully our findings can contribute to that.”
Another step forward in the upcoming UK Biobank analysis: Researchers will try to tease apart how individual score components (that each reflect a separate recommendation) drive the associations they find. The AICR/WCRF Global Cancer Update Program (formerly the AICR/WCRF Continuous Update Project) analysis has already identified different aspects of diet, physical activity and weight that are most strongly related to specific cancers. So, for example, do score components for dietary fiber or red and processed meat drive the association of a recommendations adherence score and colorectal cancer risk? What about other score components and specific cancer types?
The Cancer Prevention Recommendations were developed to provide a blueprint for a unified strategy to reduce risk of getting any cancer. So, while the individual analyses will add to advances in overall understanding of cancer prevention, it will be that big picture that’s most important for individuals and health-care professionals.
For a personal look at how your lifestyle choices are aligning with the AICR Cancer Prevention Recommendations, check out the Cancer Health Check. In just a few minutes, you’ll get an individualized assessment and recommendations for your next best steps forward.
AICR Impact: The American Institute for Cancer Research helps the public understand the relationship between lifestyle, nutrition and cancer risk. We work to prevent cancer through innovative research, community programs and impactful public health initiatives.
This announcement was originally released on August 21, 2023, by the American Institute for Cancer Research. It is republished with permission.