Emerging studies use a new standardized method to test how AICR’s Cancer Prevention Recommendations can lower the risk of many cancers and help survivors.
For years, scientists from around the world have investigated how following AICR’s Cancer Prevention Recommendations links to lowering risk of developing different cancers. Much of the research putting AICR’s Recommendations to the test is carried out by independent scientists, and the findings consistently show the Recommendations lower risk.
We’ve written about some of that here.
Several studies, presented at the 2021 AICR Research Conference, add important insights into how following AICR’s Recommendations may lower the risk of specific cancers and help survivors. Two of the studies investigate less common cancers, pancreatic and bladder, where there is scant research related to lifestyle. All of these studies score how much each participant follows an AICR Cancer Prevention Recommendation based upon a new standardized method.
Scoring the diet, weight and activity recommendations
AICR’s Recommendations were updated in 2018, developed from a rigorous analysis of the global evidence. They focus on diet, physical activity, body weight and other health-related habits that have strong evidence linking to lower cancer risk.
Like many other papers that investigate AICR’s Recommendations, these studies assigned participants a score ranging from 0 to 1 depending upon whether the person did, did not or partially followed the Recommendation. Each Recommendation has an equal weight. Using a consistent scoring method for each recommendation—such as for being physically active or eating a plant-based diet—allows for stronger comparison among the studies as to how AICR’s Recommendations affect different populations.
The studies, presented as posters at the conference, are not yet published and have not yet gone through the peer-review process.
Pancreatic cancer and AICR Recommendations
Pancreatic cancer is a relatively rare disease and often not diagnosed until it is in the late stages. AICR’s most recent report on pancreatic cancer concluded that staying a healthy weight could help lower risk of this disease.
Yet pancreatic cancer likely develops from numerous factors, and multiple lifestyle factors could play a role, says Jeanine M Genkinger , PhD, a cancer epidemiologist at Columbia University Mailman School of Public Health and lead author of a study that investigated AICR Recommendations and pancreatic cancer risk. For example, there is some research suggesting that type 2 diabetes elevates pancreatic cancer risk, and type 2 diabetes links with inactivity and sugar sweetened beverages. “That’s why we wanted to look at pancreatic cancer in a more holistic type of approach, taking into consideration all factors.”
Genkinger and her colleagues examined data from 16 population studies that included over 1.1 million individuals. Each of the studies had gathered information from the participants on their diet and lifestyle habits when they entered the study. The majority of studies began in the 1980s and early 1990s.
During the follow-up, over 5,000 cases of pancreatic cancer developed. After calculating how the participants adhered to the diet, physical activity and weight Recommendations, the study found that for every one point increase in score there was a 4 percent lower risk of pancreatic cancer. There was also a modest trend toward lower risk among those who most followed the Recommendations compared to those who least followed them. Yet this finding did not meet the statistical standards to show a clear link.
One next step, with AICR support, is to evaluate the Recommendations individually, says Genkinger, who is also examining how diet and weight change may affect pancreatic cancer risk.
Improving physical abilities among bladder cancer survivors
Previous research suggests that following AICR’s Recommendations can help cancer survivors in several ways, including physical and quality of life issues. The majority of existing research relates to the most common cancers: breast and colorectal.
Presented by Alina Vrieling, PhD, Radboud University Medical Center in The Netherlands, the new study presented at the Research Conference focuses on survivors of bladder cancer, which is the fourth most common cancer among men and far less common in women. Here, Vrieling and her colleagues wanted to see if people diagnosed with bladder cancer changed their adherence to AICR Recommendations and how these Recommendations connected to specific quality of life factors.
The study included approximately 1,000 patients in the Netherlands who had been newly diagnosed with bladder cancer. They filled out questionnaires about their pre-diagnostic diet and other lifestyle habits when diagnosed, then again at 3 months and 15 months after diagnosis. The adherence score remained constant over the study period: a 3.3 out of 7. Those who most followed the Recommendations reported having a better quality of life overall, along with improved ability to carry a heavy shopping bag, walking and other physical functions, compared to those who least followed the Recommendations. The high adherence group also reported less fatigue.
Higher adherence to the dietary and physical activity Recommendations specifically was associated with improved health-related quality of life overall. The study suggests that following AICR’s healthy lifestyle Recommendations may improve quality of life but this needs to be confirmed, note the authors.
Following more Recommendations may prevent the most common cancers
Although previous research has found AICR’s Recommendations lower risk of many common cancers, researchers in the United Kingdom wanted to test the association in a local population using the new standardized scoring system.
This study included data from approximately 109,000 participants of the UK Biobank, a large long-term study investigating genetics, environment, lifestyle and disease. The average age of the participants was 57. Again, participants were scored from 0 to 1 depending upon how much each followed AICR’s weight, diet and activity Recommendations.
During an average follow-up of 10 years, 7,484 participants were diagnosed with cancer. The most common cancers were prostate, colorectal and breast.
The study found that for every 1 point increase in adherence to the Recommendations, there was an 8 percent lower risk of cancer overall. Every 1 point increase in score also linked to a 12 percent lower risk of breast cancer and 16 percent lower risk of colorectal cancer. The lower risk here was found with both pre- and post-menopausal breast cancers. This was after taking into account age and other common risk factors.
“The findings could be interpreted as a change in any of these components that would increase the total score by 1 point,” said Fiona Malcomson, PhD, Research Associate at Newcastle University and lead author of the study. This could be going from scoring ‘0’ in the red and processed meats component (eating >500 grams of red meat per week) to scoring ‘1’ for this component (eating <500 grams of red meat per week and <21 grams of processed meat per week). Alternatively, Malcomson adds, you could improve your score by 1 point by increasing your adherence to two separate components by half a point.
When comparing the group of people who most versus least followed the Recommendations, those who scored the highest had a lower risk of cancers of all types, along with breast and colorectal specifically. However, in this study, there was no clear association between following the Recommendations and risk of prostate or lung cancers. The next step for the research team is to investigate whether giving different weightings to the Recommendations might provide new information, said Malcomson.
For more on AICR’s Cancer Prevention Recommendations and putting them into action, visit our special section for National Cancer Prevention Month.