Association between meeting the WCRF/AICR cancer prevention recommendations and colorectal cancer incidence: results from the VITAL cohort

Association of meat consumption with the risk of gastrointestinal cancers: a systematic review and meta-analysis

BACKGROUND

The association between gastrointestinal cancer and types of meat consumption, including red meat, processed meat, or a combination of both, remains disputable. Therefore, we performed a systematic review and meta-analysis of prospective cohort studies to estimate the association between meat consumption and gastrointestinal cancer risk.

METHODS

PubMed, EmBase, and the Cochrane library databases were searched systematically for eligible studies that investigated the relation between meat consumption and the risk of developing gastrointestinal cancers, including esophageal cancer (EC), gastric cancer (GC), colorectal cancer (CRC), colon cancer (CC), rectal cancer (RC), pancreatic cancer (PC), and hepatocellular carcinoma (HCC) throughout February, 2023. The pooled relative risk (RR) with 95% confidence interval (CI) was assigned as an effect estimate and calculated using a random-effects model with inverse variance weighting.

RESULTS

Forty cohorts comprising 3,780,590 individuals were selected for the final quantitative analysis. The summary results indicated that a higher red meat consumption was associated with an increased risk of CRC (RR: 1.09; 95% CI: 1.02-1.16; P = 0.007) and CC (RR: 1.13; 95% CI: 1.03-1.25; P = 0.011). Moreover, a higher processed meat consumption was associated with an increased risk of CRC (RR: 1.19; 95% CI: 1.13-1.26; P < 0.001), CC (RR: 1.24; 95% CI: 1.13-1.26; P < 0.001), and RC (RR: 1.24; 95% CI: 1.08-1.42; P = 0.002). Furthermore, a higher total consumption of red and processed meat was associated with an increased risk of CRC (RR: 1.13; 95% CI: 1.06-1.20; P < 0.001), CC (RR: 1.17; 95% CI: 1.04-1.33; P = 0.012), and RC (RR: 1.20; 95% CI: 1.04-1.39; P = 0.016). Finally, the strength of higher consumption of total red and processed meat with the risk of GC, and higher consumption of red meat with the risk of RC in subgroup of high adjusted level was lower than subgroup of moderate adjusted level, while the strength of higher consumption of processed meat with the risk of RC and HCC in subgroup of follow-up ≥ 10.0 years was higher than subgroup of follow-up < 10.0 years.

CONCLUSIONS

This study found that meat consumption was associated with an increased risk of CRC, CC, and RC, and dietary intervention could be considered an effective strategy in preventing CRC.

Adherence to a healthy lifestyle in relation to colorectal cancer incidence and all-cause mortality after endoscopic polypectomy: A prospective study in three U.S. cohorts

It remains unknown whether maintenance of a healthy lifestyle after endoscopic polypectomy could still confer benefit for colorectal cancer (CRC) incidence and mortality. In this study, we defined a healthy lifestyle score based on body mass index, smoking, physical activity, alcohol consumption and diet (range, 0-5). We used Cox proportional hazards regression to estimate the hazard ratios (HRs) for the associations of healthy lifestyle score and individual lifestyle factors with CRC incidence and all-cause mortality. During a median of 10 years of follow-up of 24 668 participants who underwent endoscopic polypectomy, we documented 161 CRC cases and 4857 all-cause deaths. A higher healthy lifestyle score after endoscopic polypectomy was associated with lower risk of CRC and all-cause mortality. Compared with individuals with 0 to 1 healthy lifestyle factors, those with 2, 3 and 4 to 5 healthy lifestyle factors had a HR for CRC risk of 0.86 (95% confidence interval [CI], 0.60-1.24), 0.73 (95% CI, 0.47-1.14) and 0.52 (95% CI, 0.27-1.01), respectively (Ptrend  = .03). The corresponding HR (95% CI) for all-cause mortality was 0.83 (95% CI, 0.76-0.90), 0.63 (95% CI, 0.56-0.70) and 0.56 (95% CI, 0.48-0.65), respectively (Ptrend  < .0001). In the joint analysis of pre- and postpolypectomy periods, patients with a healthy postpolypectomy lifestyle had a lower incidence of CRC regardless of their prepolypectomy exposure, whereas those with a healthy lifestyle in both periods had a lower mortality than those with an unhealthy lifestyle in either period. In conclusion, adherence to a healthy lifestyle after polypectomy may confer significant benefit for CRC prevention and reduction in all-cause mortality.

Combined Effect of Healthy Lifestyle Factors and Risks of Colorectal Adenoma, Colorectal Cancer, and Colorectal Cancer Mortality: Systematic Review and Meta-Analysis

Background

In addition to adiposity, lifestyle factors such as poor diet, low physical activity, alcohol intake and smoking are noted to be associated with the development of colorectal cancer (CRC). This study aims to investigate the association and dose-response relationship between adherence to a healthy lifestyle and CRC risk.

Methods

A systematic literature search was conducted in MEDLINE and EMBASE for studies examining multiple lifestyle factors with risk of CRC, incident colorectal adenoma (CRA), and CRC-specific mortality through June 2021 without restrictions on language or study design. Meta-analysis was performed to pool hazard ratios using random-effects model. Subgroup analyses were performed based upon study and sample characteristics. Random-effects dose-response analysis was also conducted for CRC risk to assess the effect of each additional healthy lifestyle factor.

Results

A total of 28 studies (18 cohort studies, eight case-control studies, and two cross-sectional study) were included. When comparing subjects with the healthiest lifestyle to those with the least healthy lifestyle, the pooled HR was statistically significant for CRC (0.52, 95% CI 0.44-0.63), colon cancer (0.54, 95% CI 0.44-0.67), rectal cancer (0.51, 95% CI 0.37-0.70), CRA (0.39, 95% CI 0.29-0.53), and CRC-specific mortality (0.65, 95% CI 0.52-0.81). The pooled HR for CRC was 0.91 (95% CI: 0.88-0.94) for each increase in the number of healthy lifestyles. The inverse association between healthy lifestyle and CRC risk was consistently observed in all subgroups (HR ranging from 0.26 to 0.86).

Conclusions

Adoption of a higher number of healthy lifestyles is associated with lower risk of CRC, CRA, and CRC-specific mortality. Promoting healthy lifestyle could reduce the burden of CRC.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=231398, identifier CRD42021231398.

Association between Nutrition Behavior and Colorectal Cancer Diet Recommendation

The incidence of colorectal cancer has considerably increased worldwide, particularly among adults aged 50 and older. Despite numerous nutrition initiatives, colorectal cancer (CRC) remains a public health burden that affects younger adults in the United States. Understanding the potential factors contributing to non-adherence to nutrition recommendations can be helpful to develop effective nutrition initiatives to prevent CRC. This study aimed to determine differences in nutrition knowledge, attitudes, and beliefs (KAB); examine their associations on diet characteristics and weight status; and identify factors influencing eating patterns among ethnically diverse populations at risk for CRC and living in urban areas. The study used a quantitative descriptive and correlational research design in which data were collected through an online cross-sectional survey. A total of 377 participants responded to the survey. The study revealed a few significant differences in KAB levels between males and females. KAB levels were not associated with weight status but with meat recommendations among overweight or obese males. Ultimately, the study identified perceived barriers and facilitators as factors influencing participants’ diets. Differences in KAB among males and females were inconsistent with the diet characteristics and weight status variables. This study suggests acknowledging these differences and inconsistencies when designing nutrition initiatives focusing on colorectal cancer prevention.

Metabolic Signatures of Healthy Lifestyle Patterns and Colorectal Cancer Risk in a European Cohort

BACKGROUND & AIMS

Colorectal cancer risk can be lowered by adherence to the World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) guidelines. We derived metabolic signatures of adherence to these guidelines and tested their associations with colorectal cancer risk in the European Prospective Investigation into Cancer and Nutrition cohort.

METHODS

Scores reflecting adherence to the WCRF/AICR recommendations (scale, 1-5) were calculated from participant data on weight maintenance, physical activity, diet, and alcohol among a discovery set of 5738 cancer-free European Prospective Investigation into Cancer and Nutrition participants with metabolomics data. Partial least-squares regression was used to derive fatty acid and endogenous metabolite signatures of the WCRF/AICR score in this group. In an independent set of 1608 colorectal cancer cases and matched controls, odds ratios (ORs) and 95% CIs were calculated for colorectal cancer risk per unit increase in WCRF/AICR score and per the corresponding change in metabolic signatures using multivariable conditional logistic regression.

RESULTS

Higher WCRF/AICR scores were characterized by metabolic signatures of increased odd-chain fatty acids, serine, glycine, and specific phosphatidylcholines. Signatures were inversely associated more strongly with colorectal cancer risk (fatty acids: OR, 0.51 per unit increase; 95% CI, 0.29-0.90; endogenous metabolites: OR, 0.62 per unit change; 95% CI, 0.50-0.78) than the WCRF/AICR score (OR, 0.93 per unit change; 95% CI, 0.86-1.00) overall. Signature associations were stronger in male compared with female participants.

CONCLUSIONS

Metabolite profiles reflecting adherence to WCRF/AICR guidelines and additional lifestyle or biological risk factors were associated with colorectal cancer. Measuring a specific panel of metabolites representative of a healthy or unhealthy lifestyle may identify strata of the population at higher risk of colorectal cancer.

Associations of Evolutionary-Concordance Diet and Lifestyle Pattern Scores with Incident, Sporadic Colorectal Adenoma in a Pooled Case-Control Study

Differences in diet and lifestyle relative to those of our Paleolithic-era ancestors may explain current high incidences of chronic diseases, including colorectal cancer (CRC), in Westernized countries. Previously reported evolutionary-concordance diet and lifestyle pattern scores, reflecting closeness of diet and lifestyle patterns to those of Paleolithic-era humans, were associated with lower CRC incidence. Separate and joint associations of the scores with colorectal adenoma among men and women are unknown. To address this, we pooled data from three case-control studies of incident, sporadic colorectal adenomas (n = 771 cases, 1,990 controls), used participants' responses to food frequency and lifestyle questionnaires to calculate evolutionary-concordance diet and lifestyle pattern scores, and estimated the scores' associations with adenomas using multivariable unconditional logistic regression. The multivariable-adjusted odds ratios comparing those in the highest relative to the lowest diet and lifestyle score quintiles were 0.84 (95% confidence interval [CI] 0.62, 1.12; P_trend:0.03) and 0.41 (95% CI 0.29, 0.59; P_trend:<0.0001), respectively. The inverse associations were stronger for high-risk adenomas, and among those with both high relative to those with both low diet and lifestyle scores. These results suggest that more evolutionary-concordant diet and lifestyle patterns, separately and jointly, may be associated with lower risk for incident, sporadic colorectal adenoma.Supplemental data for this article is available online at https://doi.org/10.1080/01635581.2021.2002919 .

Adherence to the Danish food-based dietary guidelines and risk of colorectal cancer: a cohort study

BACKGROUND

National dietary guidelines contribute to primary prevention of a wide range of diseases. Yet, the importance of adhering to the Danish dietary guidelines for colorectal cancer prevention is unclear.

METHODS

We used the Danish Diet, Cancer and Health cohort (n = 55,744) to investigate adherence to the Danish dietary guidelines and the risk of colorectal cancer. Cox proportional hazard models were used to estimate hazard ratios (HRs) for colorectal cancer and subtypes across the Danish Dietary Guidelines Index score (ranging 0-6 points, 6 being the greatest adherence). Effect modification by BMI was explored on multiplicative and additive scales.

RESULTS

During a median follow-up of 18.9 years, 1030 men and 849 women developed colorectal cancer. Higher index scores were associated with a lower risk of colorectal cancer (HR 0.66; 95% confidence interval (CI) 0.53, 0.84, highest (≥5) versus lowest index score (<3 points) group). Similar inverse associations were observed between index scores and colon cancer. The risk difference was -0.8% (95% CI: -1.6, -0.1) among the overweight/obese group and 0.1% (95% CI: -0.7, 1.0) in the normal weight group for high compared to low adherence.

CONCLUSION

Adherence to the Danish Dietary Guidelines was associated with a lower risk of colorectal cancer, particularly among people with overweight/obesity.

Comparison of four healthy lifestyle scores for predicting cardiovascular events in a national cohort study

The protective effect of different healthy lifestyle scores for the risk of cardiovascular disease (CVD) was reported, although the comparisons of performance were lacking. We compared the performance measures of CVDs from different healthy lifestyle scores among Taiwanese adults. We conducted a nationwide prospective cohort study of 6042 participants (median age 43 years, 50.2% women) in Taiwan's Hypertensive, Hyperglycemia and Hyperlipidemia Survey, of whom 2002 were free of CVD at baseline. The simple and weighted the Mediterranean diet related healthy lifestyle (MHL) scores were defined as a combination of normal body mass index, Mediterranean diet, adequate physical activity, non-smokers, regular healthy drinking, and each dichotomous lifestyle factor. The World Cancer Research Fund and American Institute for Cancer Research cancer prevention recommended lifestyle and Life's Simple 7 following the guideline definition. The incidence of CVD among the four healthy lifestyle scores, each divided into four subgroups, was estimated. During a median 14.3 years follow-up period, 520 cases developed CVD. In the multivariate-adjusted Cox proportional hazard models, adherence to the highest category compared with the lowest one was associated with a lower incidence of CVD events, based on the simple (hazard ratio [HR] 0.43, 95% confidence interval [CI] 0.2-0.94) and weighted MHL scores (HR 0.44, 95% CI 0.28-0.68). Additionally, age played a role as a significant effect modifier for the protective effect of the healthy lifestyle scores for CVD risk. Specifically, the performance measures by integrated discriminative improvement showed a significant increase after adding the simple MHL score (integrated discriminative improvement: 0.51, 95% CI 0.16-0.86, P = 0.002) and weighted MHL score (integrated discriminative improvement: 0.38, 95% CI 0.01-0.74, P = 0.021). We demonstrated that the healthy lifestyle scores with an inverse association with CVD and reduced CVD risk were more likely for young adults than for old adults. Further studies to study the mechanism of the role of lifestyle on CVD prevention are warranted.

Consumption of red meat and processed meat and cancer incidence: a systematic review and meta-analysis of prospective studies

Red meat and processed meat consumption has been hypothesized to increase risk of cancer, but the evidence is inconsistent. We performed a systematic review and meta-analysis of prospective studies to summarize the evidence of associations between consumption of red meat (unprocessed), processed meat, and total red and processed meat with the incidence of various cancer types. We searched in MEDLINE and EMBASE databases through December 2020. Using a random-effect meta-analysis, we calculated the pooled relative risk (RR) and 95% confidence intervals (CI) of the highest versus the lowest category of red meat, processed meat, and total red and processed meat consumption in relation to incidence of various cancers. We identified 148 published articles. Red meat consumption was significantly associated with greater risk of breast cancer (RR = 1.09; 95% CI = 1.03-1.15), endometrial cancer (RR = 1.25; 95% CI = 1.01-1.56), colorectal cancer (RR = 1.10; 95% CI = 1.03-1.17), colon cancer (RR = 1.17; 95% CI = 1.09-1.25), rectal cancer (RR = 1.22; 95% CI = 1.01-1.46), lung cancer (RR = 1.26; 95% CI = 1.09-1.44), and hepatocellular carcinoma (RR = 1.22; 95% CI = 1.01-1.46). Processed meat consumption was significantly associated with a 6% greater breast cancer risk, an 18% greater colorectal cancer risk, a 21% greater colon cancer risk, a 22% greater rectal cancer risk, and a 12% greater lung cancer risk. Total red and processed meat consumption was significantly associated with greater risk of colorectal cancer (RR = 1.17; 95% CI = 1.08-1.26), colon cancer (RR = 1.21; 95% CI = 1.09-1.34), rectal cancer (RR = 1.26; 95% CI = 1.09-1.45), lung cancer (RR = 1.20; 95% CI = 1.09-1.33), and renal cell cancer (RR = 1.19; 95% CI = 1.04-1.37). This comprehensive systematic review and meta-analysis study showed that high red meat intake was positively associated with risk of breast cancer, endometrial cancer, colorectal cancer, colon cancer, rectal cancer, lung cancer, and hepatocellular carcinoma, and high processed meat intake was positively associated with risk of breast, colorectal, colon, rectal, and lung cancers. Higher risk of colorectal, colon, rectal, lung, and renal cell cancers were also observed with high total red and processed meat consumption.

The associations of the Palaeolithic diet alone and in combination with lifestyle factors with type 2 diabetes and hypertension risks in women in the E3N prospective cohort

PURPOSE

Patterns of change from the traditional Palaeolithic lifestyle to the modern lifestyle may partly explain the epidemic proportions of non-communicable diseases (NCDs). We investigated to what extent adherence to the Palaeolithic diet (PD) and the Palaeolithic-like lifestyle was associated with type 2 diabetes (T2D) and hypertension risks.

METHODS

A study of 70,991 women from the E3N (Etude Epidémiologique auprès de femmes de la Mutuelle Générale de l'Education Nationale) cohort, followed up for nearly 20 years. There were 3292 incident T2D and 12,504 incident hypertension cases that were validated. Dietary data were collected at baseline in 1993 via a food frequency questionnaire. The PD score and the Palaeolithic-like lifestyle score (PD, physical activity, smoking status, and body mass index [BMI]) were derived and considered in quintiles. Multivariable Cox regression models were employed to estimate hazard ratios (HR) and 95% confidence intervals (CI) for incident T2D and hypertension.

RESULTS

In the fully adjusted models, a 1-SD increase of the PD score was associated with 4% and 3% lower risks of T2D and hypertension, respectively. Those in the highest versus the lowest quintile of the score had HR (95% CI) of 0.88 (0.79, 0.98) and 0.91 (0.86, 0.96) for T2D and hypertension, respectively (P-trend < 0.0001). Associations were stronger for the Palaeolithic-like lifestyle score; in the fully adjusted model, a 1-SD increase of the score was associated with 19% and 6% lower risks of T2D and hypertension, respectively. Risks lowered successively with each increase in quintile; those in the highest versus the lowest quintile had HR (95% CI) of 0.58 (0.52, 0.65) and 0.85 (0.80, 0.90) for T2D and hypertension, respectively (P-trend < 0.0001).

CONCLUSIONS

Our data suggest that adhering to a PD based on fruit, vegetables, lean meats, fish, and nuts, and incorporating a Palaeolithic-like lifestyle could be promising options to prevent T2D and hypertension.

Towards refining World Cancer Research Fund/American Institute for Cancer Research cancer prevention recommendations for red and processed meat intake: insights from Alberta's Tomorrow Project cohort

Current cancer prevention recommendations advise limiting red meat intake to <500 g/week and avoiding consumption of processed meat, but do not differentiate the source of processed meat. We examined the associations of processed meat derived from red v. non-red meats with cancer risk in a prospective cohort of 26 218 adults who reported dietary intake using the Canadian Diet History Questionnaire. Incidence of cancer was obtained through data linkage with Alberta Cancer Registry with median follow-up of 13·3 (interquartile range (IQR) 5·1) years. Multivariable Cox proportional hazards regression models were adjusted for covariates and stratified by age and sex. The median consumption (g/week) of red meat, processed meat from red meat and processed meat from non-red meat was 267·9 (IQR 269·9), 53·6 (IQR 83·3) and 11·9 (IQR 31·8), respectively. High intakes (4th Quartile) of processed meat from red meat were associated with increased risk of gastrointestinal cancer adjusted hazard ratio (AHR): 1·68 (95 % CI 1·09, 2·57) and colorectal cancers AHR: 1·90 (95 % CI 1·12, 3·22), respectively, in women. No statistically significant associations were observed for intakes of red meat or processed meat from non-red meat. Results suggest that the carcinogenic effect associated with processed meat intake may be limited to processed meat derived from red meats. The findings provide preliminary evidence towards refining cancer prevention recommendations for red and processed meat intake.

Meat and colorectal cancer in Middle Eastern and North African countries: update of literature review

Background

This review discusses the findings from epidemiological studies that have examined the possible role of meat and colorectal cancer (CRC) risk in Middle Eastern and North African (MENA) countries.

Methods

We conducted a literature search in the PubMed, Clinical Trials, Google Scholar, Science Direct, and Cochrane databases for observational studies that investigated the association between meat and CRC risk in adults from the MENA region.

Results

Eleven studies were included in this review. For red meat overall, significant associations were found. Regarding beef meat intake, the study included found controversial results with OR = 0.18 (95% CI 0.03–0.09). A positive association was observed between chicken and CRC risk, at OR = 2.52 (95% CI 1.33–4.77) to OR = 4.00 (95% CI 1.53–10.41) to OR = 15.32 (95% CI 3.28–71.45). A significant association was observed between processed meat intake and CRC risk, OR = 9.08 (95% CI 1.02–80.58).

Conclusion

This is the first literature review which illustrated the association between meat consumption and CRC risk in MENA region. We concluded that these studies included in this review have been controversial and not sufficient to establish a clear relationship between CRC and meat consumption in the MENA region. Further studies are necessary to be carried out in this region, with a larger sample size and submit to rigorous criteria. This review will help researchers to improve the quality of future studies about the association between CRC and nutritional diet in general and meat in particular.

Association between the 2018 WCRF/AICR and the Low-Risk Lifestyle Scores with Colorectal Cancer Risk in the Predimed Study

Limited longitudinal studies have been conducted to evaluate colorectal cancer (CRC) incidence based on the updated 2018 World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) recommendations or other global lifestyle indices, and none in aged populations at high cardiovascular risk. We aimed to assess the association between CRC incidence and adherence to two emerging lifestyles indices (2018 WCRF/AICR score and another low-risk lifestyle (LRL) score comprising smoking status, alcohol consumption, physical activity, diet, and body mass index) in the Spanish PREvencion con DIeta MEDiterranea (PREDIMED) cohort. We studied 7216 elderly men and women at high cardiovascular risk. The 2018 WCRF/AICR and LRL scores were calculated. Multivariable Cox proportional regression models were fitted to estimate the HRs (hazard ratios) and 95% confidence intervals (CIs) for incident CRC events. During a median interquartile range (IQR) follow-up of 6.0 (4.4–7.3) years, 97 CRC events were considered. A significant linear association was observed between each 1-point increment in the WCRF/AICR score (score range from 0 to 7) and CRC risk (HR (95% CI) = 0.79 (0.63–0.99)). Similarly, each 1-point increment in the LRL score (score range from 0 to 5) was associated with a 22% reduction in CRC risk (0.78 (0.64–0.96)). Adhering to emergent lifestyle scores might substantially reduce CRC incidence in elderly individuals. Further longitudinal studies, which take different lifestyle indexes into account, are warranted in the future.

Nutrition and cancer: evidence gaps and opportunities for improving knowledge

The Nutrition Society's 1st Annual Nutrition and Cancer Networking Conference brought together scientists from the fields of Nutrition, Epidemiology, Public Health, Medical Oncology and Surgery with representatives of the public, cancer survivors and cancer charities. Speakers representing these different groups presented the challenges to collaboration, how the needs of patients and the public can be met, and the most promising routes for future research. The conference programme promoted debate on these issues to highlight current gaps in understanding and barriers to generating and implementing evidence-based nutrition advice. The main conclusions were that the fundamental biology of how nutrition influences the complex cancer risk profiles of diverse populations needs to be better understood. Individual and population level genetics interact with the environment over a lifespan to dictate cancer risk. Large charities and government have a role to play in diminishing our current potently obesogenic environment and exploiting nutrition to reduce cancer deaths. Understanding how best to communicate, advise and support individuals wishing to make dietary and lifestyle changes, can reduce cancer risk, enhance recovery and improve the lives of those living with and beyond cancer.

Adherence to the World Cancer Research Fund/American Institute for Cancer Research cancer prevention guidelines and colorectal cancer incidence among African Americans and whites: The Atherosclerosis Risk in Communities study

BACKGROUND

Adherence to the World Cancer Research Fund (WCRF)/American Institute for Cancer Research (AICR) cancer prevention recommendations is associated with colorectal cancer (CRC) risk in whites, but only 1 previous study has reported on this link in African Americans. This study assessed the association between the 2018 WCRF/AICR guidelines and CRC incidence in African Americans (26.5%) and whites (73.5%) in the Atherosclerosis Risk in Communities prospective cohort (n = 13,822).

METHODS

A total of 368 incident CRC cases (268 among whites and 100 among African Americans) were identified between the baseline (1987) and 2012. A baseline adherence score was created for 7 WCRF/AICR guidelines (each contributing 0, 0.5, or 1 point to the score, with higher scores corresponding to greater adherence). Adherence scores were also categorized as tertiles (0.0-3.0, 3.5-4.0, and 4.5-7.0). Cox proportional hazards regression was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for the total cohort and with stratification by race.

RESULTS

After adjustments for age, sex, race, center, smoking, education, intake of aspirin, calcium, total calories, diabetes status, and, in women, hormone replacement therapy, greater adherence was associated with decreased CRC risk. The HRs per 1-unit increment in score were 0.88 (95% CI, 0.80-0.97) for the whole cohort, 0.89 (95% CI, 0.73-1.09) for African Americans, and 0.88 (95% CI, 0.77-0.99) for whites. Similar associations between higher adherence scores and decreased cancer risk were observed for men and women and for colon cancer but not for rectal cancer.

CONCLUSIONS

Greater adherence to the cancer prevention recommendations appears to be associated with decreased CRC risk for both African Americans and whites.

A systematic review and meta-analysis of the 2007 WCRF/AICR score in relation to cancer-related health outcomes

BACKGROUND

We conducted a systematic literature review and meta-analysis of observational studies investigating adherence to the 2007 World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) lifestyle recommendations for cancer prevention and health outcomes.

PATIENTS AND METHODS

We searched PubMed and the in-house database of the WCRF Continuous Update Project for publications up to June 2019. Cross-sectional studies were only narratively reviewed given their heterogeneity while findings of cohort/case-control studies were synthesized in umbrella reviews and meta-analyses. Summary relative risks (RRs) and 95% confidence intervals (CI) were estimated using a random-effects model when at least two studies reported results on a specific outcome.

RESULTS

Thirty-eight articles (17 prospective, 8 case-control, and 13 cross-sectional studies) were included. The summary RR per each point increment in the 2007 WCRF/AICR score was 0.90 (95% CI: 0.87-0.93, n = 11) for breast cancer, regardless of hormone receptor and menopausal status, 0.86 (95% CI: 0.82-0.89, n = 10) for colorectal cancer, and 0.93 (95% CI: 0.89-0.96, n = 2) for lung cancer risk. No statistically significant associations were reported for prostate (n = 6) and pancreatic cancers (n = 2). Adherence to the recommendations was associated with lower overall mortality (RR = 0.90, 95% CI 0.84-0.96, n = 3) and cancer-specific mortality (RR = 0.91, 95% CI 0.89-0.92; n = 3) in healthy populations, as well as with higher survival in cancer patients (n = 2). In cross-sectional studies, a healthier plasma marker profile and lower cancer risk factors in the general population and a better health status and quality of life in cancer patients/survivors were reported.

CONCLUSIONS

Adhering to the 2007 WCRF/AICR recommendations is associated with lower risks of cancer incidence, namely breast and colorectal cancers, and mortality. Primary prevention of cancer should emphasize modification of multiple lifestyle factors. Upcoming studies examining the recently updated 2018 guidelines will further clarify such associations.

Lifestyle and dietary environmental factors in colorectal cancer susceptibility

Colorectal cancer (CRC) incidence changes with time and by variations in diet and lifestyle, as evidenced historically by migrant studies and recently by extensive epidemiologic evidence. The worldwide heterogeneity in CRC incidence is strongly suggestive of etiological involvement of environmental exposures, particularly lifestyle and diet. It is established that physical inactivity, obesity and some dietary factors (red/processed meats, alcohol) are positively associated with CRC, while healthy lifestyle habits show inverse associations. Mechanistic evidence shows that lifestyle and dietary components that contribute to energy excess are linked with increased CRC via metabolic dysfunction, inflammation, oxidative stress, bacterial dysbiosis and breakdown of gut barrier integrity while the reverse is apparent for components associated with decreased risk. This chapter will review the available evidence on lifestyle and dietary factors in CRC etiology and their underlying mechanisms in CRC development. This short review will also touch upon available information on potential gene-environment interactions, molecular sub-types of CRC and anatomical sub-sites within the colorectum.

Adherence to the World Cancer Research Fund/American Institute for Cancer Research 2018 Recommendations for Cancer Prevention and Risk of Colorectal Cancer

BACKGROUND

The World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) 2018 diet, nutrition, and physical activity recommendations aim to reduce cancer risk. We examined adherence to the WCRF/AICR recommendations and colorectal cancer risk in two prospective cohorts.

METHODS

We followed 68,977 women in the Nurses' Health Study and 45,442 men in the Health Professionals Follow-up Study from 1986 until 2012. We created cumulatively averaged WCRF/AICR scores using updated diet, adiposity, and physical activity data from questionnaires, and used Cox regression to estimate sex-specific HRs and 95% confidence intervals (CI) for incident colorectal cancer.

RESULTS

We documented 2,449 colorectal cancer cases. Men in the highest quintile of the WCRF/AICR lifestyle score had a lower risk of colorectal cancer compared with those in the lowest quintile (HRQ5vsQ1 = 0.64; 95% CI, 0.52-0.77). The result was weaker in women (HRQ5vsQ1 = 0.86; 95% CI, 0.72-1.02; P heterogeneity by sex = 0.006). When analyzing the diet recommendations alone, we similarly observed stronger inverse associations in men (HRQ5vsQ1 = 0.74; 95% CI, 0.61-0.90) compared with women (HRQ5vsQ1 = 0.93; 95% CI, 0.77-1.12; P heterogeneity by sex = 0.06). In men, the lifestyle score was more strongly inversely associated with risk of distal colon cancer compared with proximal colon or rectal cancer (P common effects = 0.03); we did not observe significant differences between anatomic locations in women.

CONCLUSIONS

The 2018 WCRF/AICR cancer prevention recommendations are associated with lower colorectal cancer risk in men, with weaker results in women.

IMPACT

Consideration of adiposity and physical activity in conjunction with diet is important for colorectal cancer prevention.

Cancer Prevention with Nutrition and Lifestyle

Background

Although the crucial role of nutrition on wellbeing was known several hundreds of years ago in ancient healing methods such as traditional Chinese medicine, it often plays a minor role in modern society. However, 30-50% of all cancer cases are preventable by following a healthy diet and lifestyle, in accordance with the World Cancer Research Fund (WCRF) cancer prevention recommendations.

Summary

In addition to maintaining a healthy weight and being physically active, a balanced plant-based diet with limited amounts of fast foods, sugar-sweetened drinks, red meat, and alcohol is recommended for enhancing health. Such a way of life helps to prevent both cancer and other noncommunicable diseases (NCDs) because of the common risk factors. Although these facts are widely known, the figures are still alarming. Only a fraction of the population follows the WCRF recommendations.

Key Message

Urgent policy action is needed to promote healthy ways of living and to create health-enhancing environments to effectively reduce the risk of cancer and NCDs.

Concordance with the World Cancer Research Fund/American Institute for Cancer Research recommendations for cancer prevention and colorectal cancer risk in Morocco: A large, population-based case-control study

The present study aimed to investigate associations between adherence to the recommendations on cancer prevention from the WCRF/AICR and colorectal cancer (CRC) risk in Morocco. Incident CRC cases (n = 1,516) and controls (n = 1,516) matched on age, sex and center, were recruited between September 2009 and February 2017 at five major hospitals located in Morocco. In-person interviews were conducted to assess habitual diet using a validated Food Frequency Questionnaire, physical activity and anthropometric measurements. Adherence to the WCRF/AIRC Recommendations was ranged from 0 (no adherence) to 6 (maximal adherence) and incorporating six WCRF/AICR components (food groups, physical activity and BMI). Multivariable odd ratios (OR_A ) and 95% confidence intervals (CI) were calculated using conditional multivariate logistic regression models, with low adherence as referent, adjusting for potential confounding factors. Compared to those with the lowest adherence score, individuals in the highest WCRF/AICR score category had a statistically significant reduced risk for colon cancer (OR_A  = 0.63, 95% CI 0.53-0.76); rectal cancer (OR_A  = 0.52, 95% CI 0.43-0.63) and CRC overall (OR_A  = 0.58, 95% CI 0.51-0.66). For individual score components, when comparing the lowest with the highest adherence category, CRC risk was significantly lower in the highest adherence category for body fatness (OR_A = 0.73; 95% CI 0.62-0.85), physical activity (OR_A = 0.70; 95% CI 0.60-0.82), plant foods (OR_A = 0.50; 95% CI 0.39-0.63) and red/processed meat (OR_A = 0.81; 95% CI 0.71-0.92). Our analysis indicated that greater adherence to the WCRF/AICR recommendations for cancer prevention may lower CRC risk in Morocco.

Adherence to the World Cancer Research Fund/American Institute for Cancer Research cancer prevention recommendations and WNT-pathway-related markers of bowel cancer risk

Bowel cancer risk is strongly influenced by lifestyle factors including diet and physical activity. Several studies have investigated the effects of adherence to the World Cancer Research Fund (WCRF)/American Institute for Cancer Research (AICR) cancer prevention recommendations on outcomes such as all-cause and cancer-specific mortality, but the relationships with molecular mechanisms that underlie the effects on bowel cancer risk are unknown. This study aimed to investigate the relationships between adherence to the WCRF/AICR cancer prevention recommendations and wingless/integrated (WNT)-pathway-related markers of bowel cancer risk, including the expression of WNT pathway genes and regulatory microRNA (miRNA), secreted frizzled-related protein 1 (SFRP1) methylation and colonic crypt proliferative state in colorectal mucosal biopsies. Dietary and lifestyle data from seventy-five healthy participants recruited as part of the DISC Study were used. A scoring system was devised including seven of the cancer prevention recommendations and smoking status. The effects of total adherence score and scores for individual recommendations on the measured outcomes were assessed using Spearman's rank correlation analysis and unpaired t tests, respectively. Total adherence score correlated negatively with expression of Myc proto-oncogene (c-MYC) (P=0·039) and WNT11 (P=0·025), and high adherers had significantly reduced expression of cyclin D1 (CCND1) (P=0·042), WNT11 (P=0·012) and c-MYC (P=0·048). Expression of axis inhibition protein 2 (AXIN2), glycogen synthase kinase (GSK3β), catenin β1 (CTNNB1) and WNT11 and of the oncogenic miRNA miR-17 and colonic crypt kinetics correlated significantly with scores for individual recommendations, including body fatness, red meat intake, plant food intake and smoking status. The findings from this study provide evidence for positive effects of adherence to the WCRF/AICR cancer prevention recommendations on WNT-pathway-related markers of bowel cancer risk.

Evolutionary-Concordance Lifestyle and Diet and Mediterranean Diet Pattern Scores and Risk of Incident Colorectal Cancer in Iowa Women

Background: Whereas diet and lifestyle are strongly implicated in the etiology of colorectal cancer, single exposures generally are weakly and inconsistently associated with the disease. Exposure patterns may be more helpful for investigating diet and lifestyle-colorectal cancer associations. Evolutionary-concordance diet and Mediterranean diet pattern scores were previously found to be inversely associated with colorectal adenoma.Methods: To investigate associations of these diet scores and an evolutionary-concordance lifestyle score (comprising smoking status, physical activity, and body mass index) with incident colorectal cancer, we analyzed data from the prospective Iowa Women's Health Study. Diet and lifestyle scores were calculated for each participant and categorized into quintiles, and associations estimated using Cox proportional hazards models.Results: Of the 35,221 55- to 69-year-old cancer-free women at baseline, 1,731 developed colorectal cancer during follow-up. The multivariable-adjusted HR comparing persons in the highest relative to the lowest quintile of the lifestyle score was 0.66 (95% confidence interval, 0.56-0.78; P _trend < 0.01). Although the estimated associations of the evolutionary-concordance diet and Mediterranean diet scores alone with colorectal cancer were null, relative to those in the lowest tertiles of both the evolutionary-concordance diet and lifestyle scores, those in the highest tertiles of both scores were at the lowest risk (P _interaction < 0.01).Conclusions: Our findings suggest that a more evolutionary-concordant lifestyle, alone and in interaction with a more evolutionary-concordant diet pattern, may be inversely associated with colorectal cancer risk.Impact: These results support further investigation of colorectal cancer etiology using evolutionary-concordance dietary and lifestyle pattern scores. Cancer Epidemiol Biomarkers Prev; 27(10); 1195-202. ©2018 AACR.

Personalized Nutrition-Genes, Diet, and Related Interactive Parameters as Predictors of Cancer in Multiethnic Colorectal Cancer Families

To personalize nutrition, the purpose of this study was to examine five key genes in the folate metabolism pathway, and dietary parameters and related interactive parameters as predictors of colorectal cancer (CRC) by measuring the healthy eating index (HEI) in multiethnic families. The five genes included methylenetetrahydrofolate reductase (MTHFR) 677 and 1298, methionine synthase (MTR) 2756, methionine synthase reductase (MTRR 66), and dihydrofolate reductase (DHFR) 19bp, and they were used to compute a total gene mutation score. We included 53 families, 53 CRC patients and 53 paired family friend members of diverse population groups in Southern California. We measured multidimensional data using the ensemble bootstrap forest method to identify variables of importance within domains of genetic, demographic, and dietary parameters to achieve dimension reduction. We then constructed predictive generalized regression (GR) modeling with a supervised machine learning validation procedure with the target variable (cancer status) being specified to validate the results to allow enhanced prediction and reproducibility. The results showed that the CRC group had increased total gene mutation scores compared to the family members (p < 0.05). Using the Akaike’s information criterion and Leave-One-Out cross validation GR methods, the HEI was interactive with thiamine (vitamin B1), which is a new finding for the literature. The natural food sources for thiamine include whole grains, legumes, and some meats and fish which HEI scoring included as part of healthy portions (versus limiting portions on salt, saturated fat and empty calories). Additional predictors included age, as well as gender and the interaction of MTHFR 677 with overweight status (measured by body mass index) in predicting CRC, with the cancer group having more men and overweight cases. The HEI score was significant when split at the median score of 77 into greater or less scores, confirmed through the machine-learning recursive tree method and predictive modeling, although an HEI score of greater than 80 is the US national standard set value for a good diet. The HEI and healthy eating are modifiable factors for healthy living in relation to dietary parameters and cancer prevention, and they can be used for personalized nutrition in the precision-based healthcare era.

Predictors of the Healthy Eating Index and Glycemic Index in Multi-Ethnic Colorectal Cancer Families

For personalized nutrition in preparation for precision healthcare, we examined the predictors of healthy eating, using the healthy eating index (HEI) and glycemic index (GI), in family-based multi-ethnic colorectal cancer (CRC) families. A total of 106 participants, 53 CRC cases and 53 family members from multi-ethnic families participated in the study. Machine learning validation procedures, including the ensemble method and generalized regression prediction, Elastic Net with Akaike’s Information Criterion with correction and Leave-One-Out cross validation methods, were applied to validate the results for enhanced prediction and reproducibility. Models were compared based on HEI scales for the scores of 77 versus 80 as the status of healthy eating, predicted from individual dietary parameters and health outcomes. Gender and CRC status were interactive as additional predictors of HEI based on the HEI score of 77. Predictors of HEI 80 as the criterion score of a good diet included five significant dietary parameters (with intake amount): whole fruit (1 cup), milk or milk alternative such as soy drinks (6 oz), whole grain (1 oz), saturated fat (15 g), and oil and nuts (1 oz). Compared to the GI models, HEI models presented more accurate and fitted models. Milk or a milk alternative such as soy drink (6 oz) is the common significant parameter across HEI and GI predictive models. These results point to the importance of healthy eating, with the appropriate amount of healthy foods, as modifiable factors for cancer prevention.

Does adherence to the World Cancer Research Fund/American Institute of Cancer Research cancer prevention guidelines reduce risk of colorectal cancer in the UK Women's Cohort Study?

Evidence on adherence to diet-related cancer prevention guidelines and associations with colorectal cancer (CRC) risk is limited and conflicting. The aim of this cohort analysis is to evaluate associations between adherence to the World Cancer Research Fund/American Institute of Cancer Research (WCRF/AICR) 2007 recommendations and incident CRC. The UK Women's Cohort Study comprises over 35 372 women who filled in a FFQ at baseline in 1995. They were followed up for CRC incidence for a median of 17·4 years, an individual score linking adherence to eight of the WCRF/AICR recommendations was constructed. Cox proportional hazards regression provided hazard ratios (HR) and 95 % CI for the estimation of CRC risk, adjusting for confounders. Following exclusions, 444 CRC cases were identified. In the multivariate-adjusted model, women within the second and third (highest) categories of the WRCF/AICR score had HR of 0·79 (95 % CI 0·62, 1·00) and 0·73 (95 % CI 0·48, 1·10), respectively, for CRC compared with those in the lowest, reference category. The overall linear trend across the categories was not significant (P=0·17). No significant associations were observed between the WCRF/AICR score and proximal colon, distal colon and rectal cancers separately. Of the individual score components, a BMI within the normal weight range was borderline significantly protective only for rectal cancer in the fully adjusted model. In view of the likely different causes of CRC subtypes, further research is needed to identify the optimal dietary patterns associated with reducing colon and rectal cancer risk, respectively.

Mediating effects of cancer risk factors on the association between race and cancer incidence: analysis of the NIH-AARP Diet and Health Study

PURPOSE

Racial disparities exist in the prevalence of cancer-related risk factors and incidence of cancer. The objective of this study is to determine if cancer-related risk factors mediate the association between race and cancer incidence.

METHODS

We performed prospective analysis of data from the National Institutes of Health-American Association of Retired Persons Diet and Health Study, years 1995 through 2011. We compared differences in baseline characteristics between black and white participants using χ2 tests and Wilcoxon tests, as appropriate. We determined risk of any cancer and the most common cancer types (i.e., breast, prostate, and colorectal) using Cox Proportional hazards models, adjusted for age, sex, marital status, education, health status, region, and adherence to guidelines on cancer-related risk factors (i.e., body mass index [BMI], smoking status, physical activity, nutrition, and alcohol consumption). We examined the mediation effect of cancer-related risk factors on the association between race and cancer incidence.

RESULTS

Among 425,152 participants, 16,110 (3.79%) were black, and 409,042 (96.21%) were white. The white participants were more likely to be aged 65 years and older (35.33% vs. 25.93%), male (60.88% vs. 42.67%), married (70.37% vs. 48.26%), reside in Western US (30.14% vs. 23.88%), be physically active (46.72% vs. 41.94%), and have higher adherence scores (3.14 vs. 3.04). Blacks had reduced risk of breast cancer (adjusted hazard ratio [HR]: 0.82, 95% confidence intervals [CI]: 0.74-0.90) but higher risk of prostate (adjusted HR: 1.86, 95% CI: 1.75-1.98) and colorectal cancer (adjusted HR: 1.17, 95% CI: 1.05-1.31) compared with whites. Nutrition mediated the association between race and breast cancer (6.35% mediated, P < .01), whereas BMI mediated the association between race and colorectal cancer (7.99% mediated, P < .01).

CONCLUSIONS

Blacks were at reduced risk of breast cancer but increased risks for prostate and colorectal cancer incidence. Nutrition and BMI exerted small but significant mediating effects on the racial disparity in risk of breast and colorectal cancers, respectively.

Dietary Patterns and Colorectal Cancer Risk: A Review of 17 Years of Evidence (2000-2016)

PURPOSE OF REVIEW

Colorectal cancer (CRC) is a global public health problem, with an estimated 1.4 million cases diagnosed worldwide in 2012. Evidence suggests that diet may be important for primary prevention.

RECENT FINDINGS

The 2017 WCRF/AICR Continuous Update Project on colorectal cancer concluded that there is convincing evidence linking several individual dietary factors with CRC risk but the evidence for dietary patterns was limited and inconclusive. Also, previous reviews and meta-analyses have not critically synthesized various dietary patterns. This review synthesized data from dietary patterns studies over a 17-year period from 2000 to 2016.

SUMMARY

We included 49 studies (28 cohort and 21 case-control) that examined the association of index-based and empirically-derived dietary patterns and CRC risk. A synthesis of food group components comprising the different index-based and empirically-derived patterns revealed two distinct dietary patterns associated with CRC risk. A "healthy" pattern, generally characterized by high intake of fruits and vegetables, wholegrains, nuts and legumes, fish and other seafood, milk and other dairy products, was associated with lower CRC risk. In contrast, the "unhealthy" pattern, characterized by high intakes of red meat, processed meat, sugar-sweetened beverages, refined grains, desserts and potatoes was associated with higher CRC risk. It is notable that the number of food groups, the intake quantity, the exact types of foods in each food group, differed between populations, yet the two dietary patterns remained consistent across regions, especially in empirically-derived patterns, an indication of the high reproducibility of these patterns. However, findings for CRC risk in both index-based and empirically-derived patterns, differed by sex, with stronger associations among men than women; study design, a higher proportion of case-control studies reported significant findings compared to prospective studies. Consuming a dietary pattern high in fruits and vegetables and low in meats and sweets is protective against CRC risk. However, important questions remain about mechanisms underlying differences by sex; life-course timing of exposure to dietary patterns; interaction of dietary patterns with the microbiome or with lifestyle factors including physical activity; and elucidation of subsite differences.

Hot infusions and risk of colorectal cancer in Uruguay: a case-control study

BACKGROUND/OBJECTIVES

The evidence of possible roles for the most common hot infusions intake (tea and coffee) in the risk of colorectal cancer (CRC) needs additional data. Regarding 'mate' intake (infusion of Ilex paraguariensis herb), a previous multi-site study reported lack of association for its highest intake on CRC risk. The present study was conducted to better understand the associations between the intake of this and other infusions and CRC risk.

SUBJECTS/METHODS

Patients (611 CRC incident cases and 2394 controls, all belonging to public hospitals) were interviewed through a questionnaire, including socio-demographic, reproductive and lifestyle variables, and a food-frequency questionnaire of 64 items, analyzing tea, 'mate' and coffee intake (consumer status, daily intake, age at start and at quit). Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated through unconditional logistic regression, adjusting for relevant potential confounders.

RESULTS

Tea and coffee intake displayed significant and inverse associations with CRC risk, mainly among men (OR=0.54, 95% CI 0.38-0.76 for tea and OR=0.59, 95% CI 0.41-0.85 for coffee). Mate intake showed a significant inverse association among women (OR=0.50, 95% CI 0.33-0.77), with a marginal heterogeneity between sexes (P=0.07). Concerning age strata, tea intake displayed inverse associations in all ages, whereas 'mate' and coffee intake showed stronger inverse associations for age ⩾70, suggesting a gradient along time.

CONCLUSIONS

We found evidence of different significant inverse associations for tea, 'mate' and coffee intake and CRC risk. To our knowledge, this is the first epidemiologic study reporting inverse results on 'mate' intake and CRC, which are explained by a stronger association among women.European Journal of Clinical Nutrition advance online publication, 23 August 2017; doi:10.1038/ejcn.2017.130.