Association of total energy intake and macronutrient consumption with colorectal cancer risk: results from a large population-based case-control study in Newfoundland and Labrador and Ontario, Canada

The intake of solid fat and cheese may be associated with a reduced risk of Helicobacter pylori infection status: a cross-sectional study based on NHANES 1999-2000

BACKGROUND

Diet plays an important role in Helicobacter pylori (HP) infection, and our objective was to investigate potential connections between dietary patterns, specific food groups, and HP infection status in U.S. adults.

METHODS

The data for this study was obtained from the NHANES (National Health and Nutrition Survey) database for the year 1999-2000. This cross-sectional study involved the selection of adults aged 20 years and older who had undergone dietary surveys and HP testing. Factor analysis was employed to identify dietary patterns, and logistic regression models were utilized to assess the association between these dietary patterns and specific food groups with HP infection status.

RESULT

Based on the inclusion and exclusion criteria, our final analysis included 2,952 individuals. The median age of participants was 51.0 years, and 48.7% were male. In the study population, the overall prevalence of HP infection was 44.9%. Factor analysis revealed three distinct dietary patterns: High-fat and high-sugar pattern (including solid fats, refined grains, cheese, and added sugars); Vegetarian pattern (comprising fruits, juices, and whole grains); Healthy pattern (encompassing vegetables, nuts and seeds, and oils). Adjusted results showed that the high-fat and high-sugar pattern (OR = 0.689, 95% CI: 0.688-0.690), vegetarian pattern (OR = 0.802, 95% CI: 0.801-0.803), and healthy pattern (OR = 0.717, 95% CI: 0.716-0.718) were all linked to a lower likelihood of HP infection. Further analysis of the high-fat and high-sugar pattern revealed that solid fats (OR = 0.717, 95% CI: 0.716-0.718) and cheese (OR = 0.863, 95% CI: 0.862-0.864) were protective factors against HP infection, while refined grains (OR = 1.045, 95% CI: 1.044-1.046) and added sugars (OR = 1.014, 95% CI: 1.013-1.015) were identified as risk factors for HP infection.

CONCLUSION

Both the Vegetarian pattern and the Healthy pattern are associated with a reduced risk of HP infection. Interestingly, the High-fat and High-sugar pattern, which is initially considered a risk factor for HP infection when the score is low, becomes a protective factor as the intake increases. Within this pattern, animal foods like solid fats and cheese play a protective role, while the consumption of refined grains and added sugars increases the likelihood of HP infection.

Association between weight cycling and risk of colorectal cancer: a prospective cohort study

BACKGROUND

Weight cycling is the repeated episodes manifesting intentional weight loss and subsequent unintentional weight gain. Whether the frequency and magnitude of weight cycling is associated with colorectal cancer risk independent of body mass index (BMI) remains unknown.

METHODS

Two prospective cohort studies, Nurses' Health Study I and Health Professionals Follow-up Study, followed 85,562 participants from 1992 to 2014. Participants completed a questionnaire regarding the frequency and magnitude of intentional weight loss in the past 4 years at the baseline. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazard model.

RESULTS

We identified 1626 colorectal cancer cases during up to 22 years of follow-up. In the pooled analysis of HPFS and NHS, compared to non-weight cycling, moderate weight cycling (≥3 times of intentional weight loss of ≥2.3-4.4 kg) was associated with a reduced risk of colorectal cancer after adjustment for confounders, including attained BMI after weight cycling (HR = 0.82, 95% CI 0.69, 0.97). However, no significant association was observed in mild weight cyclers and in severe weight cyclers.

CONCLUSIONS

Moderate weight cycling was associated with a lower risk of colorectal cancer independent of BMI. This finding needs further studies for replication and putative biological mechanisms.

Dietary Factors and Early-Onset Colorectal Cancer in the United States-an Ecologic Analysis

BACKGROUND

Incidence of early-onset colorectal cancer (EOCRC; e.g., diagnosed before age 50) in the United States has increased substantially since the 1990s but the underlying reasons remain unclear.

METHODS

We examined the ecologic associations between dietary factors and EOCRC incidence in adults aged 25-49 during 1977-2016 in the United States, using negative binomial regression models, accounting for age, period, and race. The models also incorporated an age-mean centering (AMC) approach to address potential confounding by age. We stratified the analysis by sex and computed incidence rate ratio (IRR) for each study factor. Study factor data (for 18 variables) came from repeated national surveys; EOCRC incidence data came from the Surveillance Epidemiology, and End Results Program.

RESULTS

Results suggest that confounding by age on the association with EOCRC likely existed for certain study factors (e.g., calcium intake), and that AMC can alleviate the confounding. EOCRC incidence was positively associated with smoking [IRR (95% confidence interval (CI): 1.17 (1.10-1.24) for men; 1.15 (1.09-1.21) for women] and alcohol consumption [IRR (95% CI), 1.08 (1.04-1.12) for men; 1.08 (1.04-1.11) for women]. No strong associations were found for most other study factors (e.g., fiber and calcium).

CONCLUSIONS

Alcohol consumption was positively associated with EOCRC and has increased among young adults since the 1980s, which may have contributed to the EOCRC incidence increases since the 1990s. The AMC approach may help alleviate age confounding in similar ecologic analyses.

IMPACT

Increases in alcohol consumption may have contributed to the recent increases in colorectal cancer incidence among young adults. See related commentary by Ni et al., p. 164.

Contribution of macro- and micronutrients intake to gastrointestinal cancer mortality in the ONCONUT cohort: Classical vs. modern approaches

The aim of this study was to evaluate the contribution of macro- and micronutrients intake to mortality in patients with gastrointestinal cancer, comparing the classical statistical approaches with a new generation algorithm. In 1992, the ONCONUT project was started with the aim of evaluating the relationship between diet and cancer development in a Southern Italian elderly population. Patients who died of specific death causes (ICD-10 from 150.0 to 159.9) were included in the study (n = 3,505) and survival analysis was applied. This cohort was used to test the performance of different techniques, namely Cox proportional-hazards model, random survival forest (RSF), Survival Support Vector Machine (SSVM), and C-index, applied to quantify the performance. Lastly, the new prediction mode, denominated Shapley Additive Explanation (SHAP), was adopted. RSF had the best performance (0.7653711 and 0.7725246, for macro- and micronutrients, respectively), while SSVM had the worst C-index (0.5667753 and 0.545222). SHAP was helpful to understand the role of single patient features on mortality. Using SHAP together with RSF and classical CPH was most helpful, and shows promise for future clinical applications.

Association between dietary intake of fatty acids and colorectal cancer, a case-control study

Background

The association of dietary fat and colorectal cancer (CRC) was frequently reported. However, few studies assessed the effects of different types of dietary fats on CRC. This study aimed to investigate the association between intakes of different types of dietary fatty acids with colorectal cancer risk.

Methods

This case-control study was conducted on 480 participants including 160 CRC cases and 320 healthy controls in Firoozgar Hospital, Tehran, Iran. The intake of dietary fatty acids of the participants was assessed using a semi quantitative food frequency questionnaire (FFQ).

Results

The mean intake of cholesterol (273.07 ± 53.63 vs. 254.17 ± 61.12, P = 0.001), polyunsaturated fatty acids (PUFA) (16.54 ± 4.20 vs. 15.41 ± 4.44, P = 0.012), and calorie (2,568.76 ± 404.48 vs. 2,493.38 ± 176.03, P = 0.006) was higher and the mean intake of oleic acid (5.59 ± 3.17 vs. 8.21 ± 5.46) and linoleic acid (6.03 ± 3.44 vs. 7.02 ± 4.08, P = 0.01) was lower in the case group compared to the control group. An inverse association was found between colorectal cancer (CRC) and dietary intake of oleic acid (OR: 0.85, CI 95% 0.80–0.90, P = 0.001), linoleic acid (OR: 0.85, CI 95% 0.78–0.93, P = 0.001), and α-linolenic acid (OR: 0.75, CI 95% 0.57–0.98, P = 0.04). The association remained significant after adjusting for age and sex, sleep, smoking, and alcohol consumption, and BMI.

Conclusions

The results of this study support a protective effect of oleic acid, linoleic acid, and α-linolenic acid against CRC. Further longitudinal studies are warranted to confirm these results.

Dietary Risk Factors and Odds of Colorectal Adenoma in Malaysia: A Case Control Study

Current evidence suggests that dietary and lifestyle factors may play an important role in colorectal cancer risk but there are only a few studies that investigated their relationship with colorectal adenomas (CRA), the precursors for colorectal cancer. A case-control study was conducted to determine the relationship between dietary and lifestyle factors associated with CRA risk among 125 subjects with CRA and 150 subjects without CRA at Hospital Canselor Tuanku Muhriz UKM (HCTM), Malaysia. We used dietary history questionnaire (DHQ) and International Physical Activity Questionnaire-Short Form (IPAQ) to estimate the diet and physical activity. The findings of this study showed that male gender [OR = 2.71 (95% CI= 1.01-7.27)], smoking [OR = 6.39 (95% CI= 1.04-39.30)], family history of cancer [OR = 6.39 (95% CI= 1.04-39.30)], high body fat percentage [OR = 1.25 (95% CI= 1.04-1.51)], high calorie and fat intake [OR = 1.03 (95% CI= 1.01-1.06)], [OR = 1.01 (95% CI= 0.95-1.09)] and red meat intake more than 100 g per day [OR = 1.02 (95% CI= 1.01-1.04)] increased CRA risk. High fiber [OR = 0.78 (95% CI= 0.64-0.95)] and calcium intake [OR = 0.78 (95% CI= 0.98-1.00)] was found to decrease CRA risk. Some of these modifiable risk factors could be advocated as lifestyle interventions to reduce risk of CRA.

Sociodemographics and their impacts on risk factor awareness and beliefs about cancer and screening: results from a cross-sectional study in Newfoundland and Labrador

Background

Our objective was to examine cancer risk factor awareness and beliefs about cancer treatment, outcomes, and screening, and how these are mediated by sociodemographic variables, among Newfoundland and Labrador residents.

Methods

Participants aged 35 to 74 were recruited through Facebook advertising, and a self-administered online questionnaire was used to collect data. Descriptive statistics, Spearman rank correlations, and multivariate logistic regression analyses were performed.

Results

Of the 1048 participants who responded and met the inclusion criteria for this study, 1019 were selected for this analysis. Risk factor recognition was generally good, though several risk factors had poor awareness: being over 70 years old (53.4% respondents aware), having a low-fiber diet (65.0%), and drinking more than 1 unit of alcohol per day (62.8%). Our results showed that the participants’ awareness of risk factors was significantly associated with higher income level (r_s = 0.237, P <  0.001), higher education (r_s = 0.231, P <  0.001), living in rural regions (r_s = 0.163, P <  0.001), and having a regular healthcare provider (r_s = 0.081, P = 0.010). Logistic regression showed that among NL residents in our sample, those with higher income, post-secondary education, those in very good or excellent health, and those with a history of cancer all had higher odds of having more positive beliefs about cancer treatment and outcomes. Those with a history of cancer, and those with very good or excellent health, also had higher odds of having more positive beliefs about cancer screening. Finally, compared to Caucasian/white participants, those who were non-Caucasian/white had lower odds of having more positive beliefs about cancer screening.

Conclusion

Among adults in NL, there was poor awareness that low-fiber diets, alcohol, and age are risk factors for cancer. Lower income and education, rural residence, and not having a health care provider were associated with lower risk factor awareness. We also found a few associations between sociodemographic factors and beliefs about cancer treatment and outcomes or screening. We stress that while addressing awareness is necessary, so too is improving social circumstances of disadvantaged groups who lack the resources necessary to adopt healthy behaviours.

A Scaffold-Free 3-D Co-Culture Mimics the Major Features of the Reverse Warburg Effect In Vitro

Most tumors consume large amounts of glucose. Concepts to explain the mechanisms that mediate the achievement of this metabolic need have proposed a switch of the tumor mass to aerobic glycolysis. Depending on whether primarily tumor or stroma cells undergo such a commutation, the terms ‘Warburg effect’ or ‘reverse Warburg effect’ were coined to describe the underlying biological phenomena. However, current in vitro systems relying on 2-D culture, single cell-type spheroids, or basal-membrane extract (BME/Matrigel)-containing 3-D structures do not thoroughly reflect these processes. Here, we aimed to establish a BME/Matrigel-free 3-D microarray cancer model to recapitulate the metabolic interplay between cancer and stromal cells that allows mechanistic analyses and drug testing. Human HT-29 colon cancer and CCD-1137Sk fibroblast cells were used in mono- and co-cultures as 2-D monolayers, spheroids, and in a cell-chip format. Metabolic patterns were studied with immunofluorescence and confocal microscopy. In chip-based co-cultures, HT-29 cells showed facilitated 3-D growth and increased levels of hexokinase-2, TP53-induced glycolysis and apoptosis regulator (TIGAR), lactate dehydrogenase, and: translocase of outer mitochondrial membrane 20 (TOMM20), when compared with HT-29 mono-cultures. Fibroblasts co-cultured with HT-29 cells expressed higher levels of mono-carboxylate transporter 4, hexokinase-2, microtubule-associated proteins 1A/1B light chain 3, and ubiquitin-binding protein p62 than in fibroblast mono-cultures, in both 2-D cultures and chips. Tetramethylrhodamin-methylester (TMRM) live-cell imaging of chip co-cultures revealed a higher mitochondrial potential in cancer cells than in fibroblasts. The findings demonstrate a crosstalk between cancer cells and fibroblasts that affects cellular growth and metabolism. Chip-based 3-D co-cultures of cancer cells and fibroblasts mimicked features of the reverse Warburg effect.

Quantitative risk of positive family history in developing colorectal cancer: A meta-analysis

BACKGROUND

Positive family history is a risk factor for development of colorectal cancer. Despite numerous studies on the topic, the absolute risk in patients with a positive family history remains unclear and therefore studies are lacking to validate non-invasive screening methods in individuals with positive family history.

AIM

To quantify the risk of colorectal cancer in individuals with a positive family history.

METHODS

A comprehensive electronic literature search was performed using PubMed from January 1955 until November 2017, EMBASE from 1947 until 2018, and Cochrane Library without date restrictions. Two independent reviewers conducted study selection, data extraction and quality assessment. A meta-analysis of Mantel-Haenzel relative risks was performed using the random effects model. Newcastle-Ottawa scale was used to score the quality of selected papers. Funnel plot and Egger’s regression test was performed to detect publication bias. Subgroup analysis was performed comparing Asian and non-Asian studies. Sensitivity analyses were performed to rule out the effect of the timing of the study, overall quality, the main outcome and the effect of each individual study in overall result.

RESULTS

Forty-six out of 3390 studies, including 906981 patients were included in the final analysis. 41 of the included studies were case-control and 5 were cohort. A positive family history of colorectal cancer in first-degree relatives was associated with significantly increased risk of colorectal cancer with a relative risk of 1.87 (95%CI: 1.68-2.09; P < 0.00001). Cochrane Q test was significant (P < 0.00001, I² = 90%). Egger’s regression test showed asymmetry in the funnel plot and therefore the Trim and Fill method was used which confirmed the validity of the results. There was no difference between Asian versus non-Asian studies. Results remained robust in sensitivity analyses.

CONCLUSION

Individuals with a positive family history of colorectal cancer are 1.87 times more likely to develop colorectal cancer. Screening guidelines should pay specific attention to individuals with positive family history and further studies need to be done on validating current screening methods or developing new modalities in this high-risk population.

Prospective Association of Serum and Dietary Magnesium with Colorectal Cancer Incidence

BACKGROUND

Laboratory and epidemiologic research suggests a protective role of magnesium in colorectal cancer development. We estimated the associations of serum and dietary magnesium with colorectal cancer incidence in the Atherosclerosis Risk in Communities (ARIC) study.

METHODS

Serum magnesium concentration was measured in blood collected twice (1987-1989 and 1990-1992) and averaged. Dietary magnesium was assessed by food-frequency questionnaire administered twice (1987-1989 and 1993-1995) and averaged. For both dietary and serum magnesium, the averaged measures were categorized into quintiles for analysis. Analyses included 315 colorectal cancer cases among 13,009 participants for serum magnesium (followed for a median of 20.4 years), and 256 cases among 10,971 participants for dietary magnesium (followed for a median of 17.5 years). Cox proportional hazards regression was used to calculate multivariable-adjusted HRs and 95% confidence intervals (CI).

RESULTS

Multivariable-adjusted HRs (95% CI) of colorectal cancer for the highest four quintiles compared with the first quintile of serum magnesium were as follows: Q2: 0.70 (0.49-0.99); Q3: 0.68 (0.47-1.00); Q4: 0.87 (0.62-1.21); and Q5: 0.79 (0.57-1.11; P trend = 0.04). An inverse association was present in females (HR for Q5 vs. Q1: 0.59, 95% CI: 0.36-0.98, P trend = 0.01), but not males (HR for Q5 vs. Q1: 1.10, 95% CI: 0.67-1.79, P trend = 0.92; P interaction = 0.34). Dietary magnesium was not statistically significantly associated with colorectal cancer risk.

CONCLUSIONS

Our study found a higher risk of colorectal cancer with lower serum magnesium among females, but not males.

IMPACT

If our findings are confirmed, maintaining adequate serum magnesium levels may be important for colorectal cancer prevention.

A Reasonable Diet Promotes Balance of Intestinal Microbiota: Prevention of Precolorectal Cancer

Colorectal cancer (CRC) is a multifactorial disease and the second leading cause of cancer death worldwide. The pathogenesis of colorectal cancer includes genetics, age, chronic inflammation, and lifestyle. Increasing attention has recently been paid to dietary factors. Evidence from epidemiological studies and clinical research suggests that high-fibre diets can significantly reduce the incidence of CRC, whilst the consumption of high-fat diets, high-protein diets, red meat, and processed meat is high-risk factors for tumorigenesis. Fibre is a regulator of intestinal microflora and metabolism and is thus a key dietary component for maintaining intestinal health. Intestinal microbes are closely linked to CRC, with the growth of certain microbiota (such as Fusobacterium nucleatum, Escherichia coli, or Bacteroides fragilis) favouring carcinogenesis, whilst the dominant microbiota population of the intestine, such as Bacteroidetes, Firmicutes, Actinobacteria, and Proteobacteria, have multiple mechanisms of antitumour activity. Various dietary components have direct effects on the types of intestinal microflora: in the Western diet mode (high-fat, high-protein, and red meat), the proportion of conditional pathogens in the intestinal flora increases, the proportion of commensal bacteria decreases, and the occurrence of colorectal cancer is promoted. Conversely, a high-fibre diet can increase the abundance of Firmicutes and reduce the abundance of Bacteroides and consequently increase the concentration of short-chain fatty acids (SCFAs) in the intestine, inhibiting the development of CRC. This article reviews the study of the relationship between diet, intestinal microbes, and the promotion or inhibition of CRC and analyses the relevant molecular mechanisms to provide ideas for the prevention and treatment of CRC.

Dietary Fat Intake and Risk of Colorectal Cancer: A Systematic Review and Meta-Analysis of Prospective Studies

Dietary fat intake is associated with the risk of colorectal cancer (CRC); however, the results of epidemiological studies on this are controversial. Therefore, this study aimed to summarize the available scientific evidence regarding the association between dietary fat and the risk of CRC. We conducted a systematic search of PubMed, Web of Science, and the Cochrane library for articles related to dietary fat and the risk of CRC. The summary relative risks with 95% confidence intervals (CI) were calculated via a random effect model. Begg’s test was used to detect publication bias. A total of 18 articles were identified. The pooled relative risk with 95% CI for the risk of CRC were 1.00 (95% CI: 0.90–1.12), 0.97 (95% CI: 0.86–1.10), 1.08 (95% CI: 0.92–1.26), and 0.99 (95% CI: 0.93–1.04) for total fat, saturated fatty acid, monounsaturated fatty acid, and polyunsaturated fatty acid, respectively. No significant associations were found in subgroup analyses. Begg’s test for all exposures revealed no publication bias (total fat, p = 0.3; saturated fatty acid, p = 0.1; monounsaturated fatty acid, p = 0.08; polyunsaturated fatty acid, p = 0.2). The studies included in this review and meta-analysis revealed that dietary fats and fatty acids had no effects on the risk of CRC.

Dietary Walnuts Protect Against Obesity-Driven Intestinal Stem Cell Decline and Tumorigenesis

Obesity can negatively impact intestinal homeostasis, and increase colon cancer risk and related mortality. Thus, given the alarmingly high rates of obesity in the US and globally, it is critical to identify practical strategies that can break the obesity-cancer link. Walnuts have been increasingly recognized to mitigate cancer risk, and contain many bioactive constituents with antioxidant and anti-inflammatory properties that could potentially counteract pathways thought to be initiators of obesity-related cancer. Therefore, the purpose of this study was to determine if walnuts could preserve intestinal homeostasis, and attenuate tumorigenesis and growth in the context of obesity and a high calorie diet. To this end, we studied effects of walnuts on these parameters under different dietary conditions in wildtype mice, two independent Apc models (Apc^1638N/+ and Apc^Δ14), and in MC38 colon cancer cells in vivo, respectively. Walnuts did not alter the metabolic phenotype or intestinal morphology in normal mice fed either a low-fat diet (LFD), LFD with 6% walnuts (LFD+W), high-fat diet (HFD), or HFD with 7.6% walnuts (HFD+W). However, walnuts did lead to a significant reduction in circulating CCL5 and preserved intestinal stem cell (ISC) function under HFD-fed conditions. Furthermore, walnuts reduced tumor multiplicity in Apc^1638N/+ male HFD+W animals, as compared to HFD controls (3.7 ± 0.5 vs. 2.5 ± 0.3; P = 0.015), tended to reduce the number of adenocarcinomas (0.67 ± 0.16 vs. 0.29 ± 0.12; P = 0.07), and preferentially limited tumor growth in Apc^Δ14 male mice (P = 0.019) fed a high-calorie western-style diet. In summary, these data demonstrate that walnuts confer significant protection against intestinal tumorigenesis and growth and preserve ISC function in the context of a high-calorie diet and obesity. Thus, these data add to the accumulating evidence connecting walnuts as a potentially effective dietary strategy to break the obesity-colon cancer link.

Hypothesis and data-driven dietary patterns and colorectal Cancer survival: findings from Newfoundland and Labrador colorectal Cancer cohort

Background

Dietary patterns are commonly used in epidemiological research, yet there have been few studies assessing if and how research results may vary across dietary patterns. This study aimed to estimate the risk of mortality/recurrence/metastasis using different dietary patterns and comparison amongst the patterns.

Methods

Dietary patterns were identified by Cluster Analysis (CA), Principal Component Analysis (PCA), Alternate Mediterranean Diet score (altMED), Recommended Food Score (RFS) and Dietary Inflammatory Index (DII) scores using a 169-item food frequency questionnaire.

Five hundred thirty-two colorectal cancer patients diagnosed between 1999 and 2003 in Newfoundland were followed-up until 2010. Overall Mortality (OM) and combined Mortality, Recurrence or Metastasis (cMRM) were identified. Comparisons were made with adjusted Cox proportional Hazards Ratios (HRs), correlation coefficients and the distributions of individuals in defined clusters by quartiles of factor and index scores.

Results

One hundred and seventy cases died from all causes and 29 had a cancer recurrence/metastasis during follow-up. Processed meats as classified by PCA (HR 1.82; 95% confidence interval (CI) 1.07–3.09), clusters characterized by meat and dairy products (HR 2.19; 95% CI 1.03–4.67) and total grains, sugar, soft drinks (HR 1.95; 95% CI 1.13–3.37) were associated with a higher risk of cMRM. Poor adherence to AltMED increased the risk of all-cause OM (HR 1.62; 95% CI 1.04–2.56). Prudent vegetable, high sugar pattern, RFS and DII had no significant association with both OM and cMRM.

Conclusion

Estimation of OM and cMRM varied across dietary patterns which is attributed to the differences in the foundation of each pattern.

Electronic supplementary material

The online version of this article (10.1186/s12937-018-0362-x) contains supplementary material, which is available to authorized users.

The association between dietary protein intake and colorectal cancer risk: a meta-analysis

BACKGROUND

Association between dietary protein intake and colorectal cancer risk has not been fully quantified, while the results were controversial. This study aimed to evaluate the role of protein intake in the development of colorectal cancer.

METHODS

PUBMED and EMBASE were searched up to December 2016. Two independent reviewers independently extracted data from eligible studies. Relative risk (RR) with 95% confidence intervals (CI) was pooled using random-effects model to estimate the result. Besides, publication bias and sensitivity analysis were conducted.

RESULTS

Thirteen articles involving 21 studies comprising 8187 cases were included in this report. The pooled RR of colorectal cancer was 1.006 (95% CI = 0.857-1.179) indicating that there is no significant association between dietary protein intake and colorectal cancer risk. Furthermore, the pooled RRs for colon cancer and rectum cancer were 1.135(95% CI = 0.871-1.480) and 0.773(95% CI = 0.538-1.111), respectively, with the highest category of dietary protein intake. The association was not significant either in subgroup analysis of study design, protein type (animal protein or vegetable protein), sex, and or geographic locations.

CONCLUSIONS

The present study indicated that the highest category compared to the lowest category of protein intake had no significant association on colorectal cancer risk. Dose-response analysis was not conducted due to limited information provided. Therefore, more studies with large cases and participants as well as detailed amounts of dietary protein intake are wanted to confirm this result.

Inflammatory diet and risk for colorectal cancer: A population-based case-control study in Newfoundland, Canada

OBJECTIVE

Chronic inflammation is implicated in causing cancer. Diet plays an important role in regulating chronic inflammation by altering circulating levels of inflammatory biomarkers. Effect of single food or nutrient on cancer often is inconclusive; perhaps due to dietary interactions and multicolinearity. The aim of this study was to determine prediagnostic inflammatory potential of overall diet in relation to risk for colorectal cancer (CRC).

METHODS

In all, 547 patients with CRC from Newfoundland Familial Colorectal Cancer Registry and 685 controls from the general population were identified. Data on sociodemographic, medical history, lifestyle, and a 169-item food frequency questionnaire were collected retrospectively from both groups. Energy-adjusted Dietary Inflammatory Index (DII) score was calculated and used as both categorical and continuous variables for analysis. Odds ratio was estimated using multivariable logistic regression after adjusting potential confounders. A linear test for trend was performed using the median value in each quartile.

RESULTS

Overall energy-adjusted mean DII score was -0.81 (range -5.19 to 6.93). Cases (-0.73 ± 1.5) had slightly higher DII scores than controls (-0.89 ± 1.6; P = 0.04). After adjusting the potential confounders, a statistically significant association was found between DII score and CRC risk. Using DII as a continuous variable (odds ratio [OR]_continuous 1.10, 95% confidence interval [CI] 1.01-1.20) and categorical variable (OR_{quartile 1 versus 4} 1.65, 95% CI 1.13-2.42; P_trend = 0.02).

CONCLUSION

Our findings indicate that proinflammatory diets are associated with an increased risk for CRC in the Newfoundland population.

A meta-analysis between dietary carbohydrate intake and colorectal cancer risk: evidence from 17 observational studies

The association between dietary carbohydrate intake and colorectal cancer (CRC) risk remains controversial. We therefore conducted this meta-analysis to assess the relationship between them. A literature search from the databases of PubMed, Embase, Web of Science and Medline was performed for available articles published in English (up to September 2016). Pooled relative risk (RR) with 95% confidence interval (CI) was calculated to evaluate the association between dietary carbohydrate intake and CRC risk. The random-effect model (REM) was selected as the pooling method. Publication bias was estimated using Egger’s regression asymmetry test and funnel plot. A total of 17 articles involving 14402 CRC patients and 846004 participants were eligible with the inclusion criteria in this meta-analysis. The pooled RR with 95% CI of dietary carbohydrate intake for CRC, colon cancer and rectum cancer risk were 1.08 (95% CI =0.93–1.23, I² =68.3%, P_{heterogeneity}<0.001), 1.09 (95% CI =0.95–1.25, I² =48.3%) and 1.17 (95% CI =0.98–1.39, I² =17.8%) respectively. When we conducted the subgroup analysis by gender, the significant association was found in men’s populations (summary RR =1.23, 95% CI =1.01–1.57), but not in the women’s populations. In the further subgroup analyses for study design and geographic locations, we did not find any association between dietary carbohydrate intake and CRC risk in the subgroup results respectively. No significant publication bias was found either by the Egger’s regression asymmetry test or by the funnel plot. This meta-analysis suggested that higher dietary carbohydrate intake may be an increased factor for CRC risk in men populations. Further studies are wanted to confirm this relationship.

Self-Report Dietary Assessment Tools Used in Canadian Research: A Scoping Review

Choosing the most appropriate dietary assessment tool for a study can be a challenge. Through a scoping review, we characterized self-report tools used to assess diet in Canada to identify patterns in tool use and to inform strategies to strengthen nutrition research. The research databases Medline, PubMed, PsycINFO, and CINAHL were used to identify Canadian studies published from 2009 to 2014 that included a self-report assessment of dietary intake. The search elicited 2358 records that were screened to identify those that reported on self-report dietary intake among nonclinical, non-Aboriginal adult populations. A pool of 189 articles (reflecting 92 studies) was examined in-depth to assess the dietary assessment tools used. Food-frequency questionnaires (FFQs) and screeners were used in 64% of studies, whereas food records and 24-h recalls were used in 18% and 14% of studies, respectively. Three studies (3%) used a single question to assess diet, and for 3 studies the tool used was not clear. A variety of distinct FFQs and screeners, including those developed and/or adapted for use in Canada and those developed elsewhere, were used. Some tools were reported to have been evaluated previously in terms of validity or reliability, but details of psychometric testing were often lacking. Energy and fat were the most commonly studied, reported by 42% and 39% of studies, respectively. For ∼20% of studies, dietary data were used to assess dietary quality or patterns, whereas close to half assessed ≤5 dietary components. A variety of dietary assessment tools are used in Canadian research. Strategies to improve the application of current evidence on best practices in dietary assessment have the potential to support a stronger and more cohesive literature on diet and health. Such strategies could benefit from national and global collaboration.

MicroRNA biomarkers predicting risk, initiation and progression of colorectal cancer

Colorectal cancer is a major global cause of morbidity and mortality. Current strategies employed to increase detection of early, curable stages of this disease are contributing to a reduction of the negative health impact from it. While there is a genetic component to the risk of disease, diet and environment are known to have major effects on the risk of an individual for developing the disease. However, there is the potential to reduce the impact of this disease further by preventing disease development. Biomarkers which can either predict the risk for or early stages of colorectal cancer could allow intervention at a time when prospects could be modified by environmental factors, including lifestyle and diet choices. Thus, such biomarkers could be used to identify high risk individuals who would benefit from lifestyle and dietary interventions to prevent this disease. This review will give an overview on one type of biomarker in the form of microRNAs, which have the potential to predict an individual’s risk for colorectal cancer, as well as providing a highly sensitive and non-invasive warning of disease presence and/or progression. MicroRNA biomarkers which have been studied and whose levels look promising for this purpose include MiR-18a, MiR-21, MiR-92a, MiR-135b, MiR-760, MiR-601. Not only have several individual microRNAs appeared promising as biomarkers, but panels of these may be even more useful. Furthermore, understanding dietary sources and ways of dietary modulation of these microRNAs might be fruitful in reducing the incidence and slowing the progression of colorectal cancer.

Meats, milk and fat consumption in colorectal cancer

BACKGROUND

Data from several studies suggest that a diet high in meat, including processed meat and fat, may have an association with the development of colorectal cancer (CRC).

METHODS

The present study aimed to investigate the relationship between meats, dairy products, fat consumption and the risk of CRC in Jordanians. A case-control study was performed at the five largest hospitals in Jordan. Dietary data were collected from 220 diagnosed cases of CRC and 281 healthy disease-free controls. The CRC cases were matched as closely as possible to controls using age, sex, occupation and marital status.

RESULTS

The consumption of different levels and frequencies of several food types, including meats, chicken, milk and fish, was found to be associated with the risk of developing CRC. Added fats and oils were inversely associated with CRC risk with odds ratio = 0.33 (95% confidence interval = 0.13-0.83, P_trend = 0.005). The predominant fat added by cases and controls was olive oil, followed by corn oil.

CONCLUSIONS

The results of the study suggest that the consumption of some types of meat, processed meats and Labaneh (strained yogurt) may be associated with the risk of developing CRC.

Healthy Lifestyle Pattern is Protective Against 30-Yr Cancer Incidence in Men and Women: A Cohort Study

OBJECTIVES

Investigate associations of healthier behaviors with 30-yr cancer incidence.

SUBJECTS/METHODS

In 1982, 632 healthy men and women (ages 40-70) were interviewed for nutritional habits using a Food Frequency Questionnaire and a 24-h physical activity questionnaire. Blood pressure, weight, and height were measured, and blood was drawn for biochemical profiles. Thirteen and four subjects were excluded due to cancer diagnosis ≤1 yr from recruitment and extreme values of reported total daily calorie intake, respectively.

RESULTS

During a mean follow-up of 24.2 yr, 146 cancer incident patients (23.7%) were documented. Total cancer risk was 38% lower in the medium vegetable intake tertile [adjusted hazards ratio (HR) = 0.62, 95%confidence interval (CI): 0.40-0.95], and 66% higher in the medium fruit intake tertile (adjusted HR = 1.66, 95%CI: 1.08-2.55) compared to the lowest tertile. The risk of gastrointestinal cancers was 3 times greater for the highest, compared to the lowest, dairy consumption tertile (HR = 3.06, 95%CI: 1.01-9.23). "Healthy lifestyle" (normal BMI, never smoked, consuming high levels of dietary fiber and vegetables, and more physically active) reduced overall cancer risk (adjusted HR = 0.63, 95%CI: 0.44-0.91) as compared to the rest of the cohort.

CONCLUSIONS

Our findings reinforce the importance of lifestyle-related factors, which are relatively low-cost and may contribute to reduction in the burden of malignant diseases.

Comparison in dietary patterns derived for the Canadian Newfoundland and Labrador population through two time-separated studies

Background

While a dietary pattern is often believed to be stable in a population, there is limited research assessing its stability over time. The objective of this study is to explore and compare major dietary patterns derived for the Canadian subpopulation residing in Newfoundland and Labrador (NL), through two time-separated studies using an identical method.

Methods

In this study, we derived and compared the major dietary patterns derived from two independent studies in the NL adult population. The first study was based on the healthy controls from a large population-based case–control study (CCS) in 2005. The second was from a food-frequency questionnaire validation project (FFQVP) conducted in 2012. In both studies, participants were recruited in the same manner and dietary information was collected by an identical self-administered food-frequency questionnaire (FFQ). Exploratory common factor analysis was conducted to identify major dietary patterns. A comparison was conducted between the two study populations.

Results

Four major dietary patterns were identified: Meat, Vegetables/fruits, Fish, and Grains explaining 22 %, 20 %, 12 % and 9 % variance respectively, with a total variance of 63 %. Three major dietary patterns were derived for the controls of the CCS: Meat, Plant-based diet, and Fish explaining 24 %, 20 %, and 10 % variance respectively, with a total variance of 54 %. As the Plant-based diet pattern derived for the CCS was a combination of the Vegetables/fruits and Grains patterns derived for the FFQVP, no considerable difference in dietary patterns was found between the two studies.

Conclusion

A comparison between two time-separated studies suggests that dietary patterns of the NL adult population have remained reasonably stable over almost a decade.

Inhibitory effect of various breads on DMH-induced aberrant crypt foci and colorectal tumours in rats

Bread is rich in dietary fibre and many phytochemical compounds, which may influence chemoprevention of colon cancer. In the present study, we evaluated the effect of three kinds of bread on DMH-induced colorectal tumours in F344 rats. F344 rats were divided into four groups (Steinmetz Three-Grain bread, Steinmetz Country bread, White bread, and MF). All groups were injected with 1,2-dimethylhydrazine (DMH, 20 mg/kg body weight) once a week for 8 consecutive weeks from 5 weeks of age. To investigate the antioxidant effect of bread, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging rate of bread and the serum levels of 8-hydroxy-deoxyguanosine (8-OHdG) in rats were examined. The number of colorectal aberrant crypt foci (ACF) and the incidence of colorectal tumours were studied after 34 weeks of DMH treatment. The Steinmetz Three-Grain and Steinmetz Country bread groups had higher scavenging rates of the DPPH free radical and lower serum levels of 8-OHdG and incidence of ACF, adenomas, and adenocarcinomas of colon than the White bread and MF group. Steinmetz Three-Grain bread and Steinmetz Country bread have various ingredient combinations that may inhibit colorectal cancer progression.

Macro- and micronutrients consumption and the risk for colorectal cancer among Jordanians

OBJECTIVE

Diet and lifestyle have been reported to be important risk factors for the development of colorectal cancer (CRC). However, the association between total energy and nutrient intake and the risk of developing CRC has not been clearly explained. The aim of our study is to examine the relationship between total energy intake and other nutrients and the development of CRC in the Jordanian population.

RESEARCH METHODS AND PROCEDURES

Dietary data was collected from 169 subjects who were previously diagnosed with CRC, and 248 control subjects (matched by age, gender, occupation and marital status). These control subjects were healthy and disease free. Data was collected between January 2010 and December 2012, using interview-based questionnaires. Logistic regression was used to evaluate the association between quartiles of total energy, macro- and micronutrient intakes with the risk of developing CRC in our study population.

RESULTS

Total energy intake was associated with a higher risk of developing CRC (OR = 2.60 for the highest versus lowest quartile of intake; 95% CI: 1.21-5.56, p-trend = 0.03). Intakes of protein (OR = 3.62, 95% CI: 1.63-8.05, p-trend = 0.002), carbohydrates (OR = 1.41, 95% CI: 0.67-2.99, p-trend = 0.043), and percentage of energy from fat (OR = 2.10, 95% CI: 0.38-11.70, p-trend = 0.009) significantly increased the risk for the development of CRC. Saturated fat, dietary cholesterol and sodium intake showed a significant association with the risk of developing CRC (OR = 5.23, 95% CI: 2.33-11.76; OR = 2.48, 95% CI: 1.18-5.21; and OR = 3.42, 95% CI: 1.59-7.38, respectively), while vitamin E and caffeine intake were indicative of a protective effect against the development of CRC, OR = 0.002 (95% CI: 0.0003-0.011) and 0.023 (95%CI: 0.008-0.067), respectively.

CONCLUSION

Our results suggest an increased risk for the development of CRC in subjects with high dietary intake of energy, protein, saturated fat, cholesterol, and sodium, and diets high in vitamin E and caffeine were suggestive of a protective effect against the risk of developing CRC.

IMPACT

This is the first study in Jordan to suggest that it may be possible to reduce CRC risk by adjusting the intake of some macro-and micronutrients.

The role of dietary and lifestyle factors in the development of colorectal cancer: case control study in Minia, Egypt

BACKGROUND

Colorectal cancer (CRC) is the third most common cancer worldwide, after lung and breast cancer, and is associated with the population dietary and lifestyle factors.

AIM

To determine the relation between dietary and lifestyle factors and development of CRC in patients attending Minia oncology centre and compare them with their control.

METHODS

Study included 150 CRC patients attending Minia oncology centre and 300 control subjects matched by age and sex. Subjects participating in the study filled in a questionnaire including questions about socio-demographic data, medical data concerning CRC and its treatment as well as dietary and lifestyle factors.

RESULTS

The most significant dietary and lifestyle CRC risk factors were higher consumption of red meat (OR = 57.1), preserved food (OR = 39.4), artificial sweeteners (OR = 20.8), fast foods (OR = 12.8), soft drinks (OR = 4.6), spicy foods (OR = 4.2), processed meat (OR = 2.4), and smoking (OR = 8.8). The most significant protective factors were physical activity (OR = 0.001), calcium rich diet (OR = 0.08), higher consumption of fruits and vegetable (OR = 0.02), cruciferous vegetables (broccoli OR = 0.11, cauliflower OR = 0.30 and cabbage OR = 0.30), high fiber bread (OR = 0.15), fruit juice (OR = 0.18), and sea foods (tuna OR = 0.28 and fish OR = 0.38).

CONCLUSION

Sedentary lifestyle and unhealthy dietary choices were prevalent among CRC cases. This study provides strong evidence that lifestyle and dietary modification are important factors in the prevention of colorectal cancer.

Dietary patterns and colorectal cancer: results from a Canadian population-based study

Background

The relationship between major dietary patterns and colorectal cancer (CRC) in other populations largely remains consistent across studies. The objective of the present study is to assess if dietary patterns are associated with the risk of CRC in the population of Newfoundland and Labrador (NL).

Methods

Data from a population based case–control study in the province of NL were analyzed, including 506 CRC patients (306 men and 200 women) and 673 controls (400 men and 273 women), aged 20–74 years. Dietary habits were assessed by a 169-item food frequency questionnaire (FFQ). Logistic regression analyses were performed to investigate the association between dietary patterns and the CRC risk.

Results

Three major dietary patterns were derived using factor analysis, namely a Meat-diet pattern, a Plant-based diet pattern and a Sugary-diet pattern. In combination the three dietary patterns explained 74% of the total variance in food intake. Results suggest that the Meat-diet and the Sugary-diet increased the risk of CRC with corresponding odds ratios (ORs) of 1.84 (95% CI: 1.19-2.86) and 2.26 (95% CI: 1.39-3.66) for people in the highest intake quintile compared to those in the lowest. Whereas plant-based diet pattern decreases the risk of CRC with a corresponding OR of 0.55 (95% CI: 0.35-0.87). Even though odds ratios (ORs) were not always statistically significant, largely similar associations across three cancer sites were found: the proximal colon, the distal colon, and the rectum.

Conclusion

The finding that Meat-diet/Sugary-diet patterns increased and Plant-based diet pattern decreased the risk of CRC would guide the promotion of healthy eating for primary prevention of CRC in this population.

Colorectal carcinogenesis-update and perspectives

Colorectal cancer (CRC) is a very common malignancy in the Western World and despite advances in surgery, chemotherapy and screening, it is still the second leading cause of cancer deaths in this part of the world. Numerous factors are found important in the development of CRC including colonocyte metbolism, high risk luminal environment, inflammation, as well as lifestyle factors such as diet, tobacco, and alchohol consumption. In recent years focus has turned towards the genetics and molecular biology of CRC and several interesting and promising correlations and pathways have been discovered. The major genetic pathways of CRC are the Chromosome Instability Pathway representing the pathway of sporadic CRC through the K-ras, APC, and P53 mutations, and the Microsatellite Instability Pathway representing the pathway of hereditary non-polyposis colon cancer through mutations in mismatch repair genes. To identify early cancers, screening programs have been initiated, and the leading strategy has been the use of faecal occult blood testing followed by colonoscopy in positive cases. Regarding the treatment of colorectal cancer, significant advances have been made in the recent decade. The molecular targets of CRC include at least two important cell surface receptors: the epidermal growth factor receptor and the vascular endothelial growth factor receptor. The genetic and molecular knowledge of CRC has widen the scientific and clinical perspectives of diagnosing and treatment. However, despite significant advances in the understanding and treatment of CRC, results from targeted therapy are still not convincing. Future studies will determine the role for this new treatment modality.

The association of percentage energy from fat and colon cancer risk among members of the US military

Epidemiologic studies have previously reported an association between high fat intake and colon cancer risk. However, findings have generally been inconclusive. This study aimed to investigate the association between fat as a percentage of energy intake and colon cancer risk. Study subjects included 215 cases and 215 matched controls identified by the Defense Medical Surveillance System. Percentage energy from fat (Pfat) was estimated using a short dietary screener developed by the National Cancer Institute for two time periods: the year before the first blood draw and the year before colon cancer diagnosis. Conditional logistic regression analysis was used to assess the relationship between colon cancer risk and Pfat. Odds ratios and 95% confidence intervals (CIs) were calculated. Compared with the lowest quartile of Pfat, the adjusted odds of having colon cancer were 2.00 (95% CI 0.96-4.18), 2.83 (95% CI 1.41-5.66), and 3.37 (95% CI 1.58-7.17), respectively, for the second, third, and highest quartiles in the year before cancer diagnosis. Similar results were observed for Pfat at an earlier time point. Our findings suggest a positive association between Pfat and colon cancer in the US military population.

Assessing the validity of a self-administered food-frequency questionnaire (FFQ) in the adult population of Newfoundland and Labrador, Canada

BACKGROUND

The Food- Frequency Questionnaire (FFQ) is a dietary assessment tool frequently used in large-scale nutritional epidemiology studies. The goal of the present study is to validate a self-administered version of the Hawaii FFQ modified for use in the general adult population of Newfoundland and Labrador (NL).

METHODS

Over a one year period, 195 randomly selected adults completed four 24-hour dietary recalls (24-HDRs) by telephone and one subsequent self-administered FFQ. Estimates of energy and nutrients derived from the 24-HDRs and FFQs were compared (protein, carbohydrate, fibre, fat, vitamin A, carotene, vitamin D, and calcium). Data were analyzed using the Pearson's correlation coefficients, cross-classification method, and Bland-Altman plots.

RESULTS

The mean nutrient intake values of the 24-HDRs were lower than those of the FFQs, except for protein in men. Sex and energy-adjusted de-attenuated Pearson correlation coefficients for each nutrient varied from 0.13 to 0.61. Except for protein in men, all correlations were statistically significant with p < 0.05. Cross-classification analysis revealed that on average, 74% women and 78% men were classified in the same or adjacent quartile of nutrient intake when comparing data from the FFQ and 24-HDRs. Bland-Altman plots showed no serious systematic bias between the administration of the two instruments over the range of mean intakes.

CONCLUSION

This 169-item FFQ developed specifically for the adult NL population had moderate relative validity and therefore can be used in studies to assess food consumption in the general adult population of NL. This tool can be used to classify individual energy and nutrient intakes into quartiles, which is useful in examining relationships between diet and chronic disease.

Dietary patterns and colorectal cancer recurrence and survival: a cohort study

OBJECTIVE

To examine the association between dietary patterns and colorectal cancer (CRC) survival.

DESIGN

Cohort study.

SETTING

A familial CRC registry in Newfoundland.

PARTICIPANTS

529 newly diagnosed CRC patients from Newfoundland. They were recruited from 1999 to 2003 and followed up until April 2010.

OUTCOME MEASURE

Participants reported their dietary intake using a food frequency questionnaire. Dietary patterns were identified with factor analysis. Multivariable Cox proportional hazards models were employed to estimate HR and 95% CI for association of dietary patterns with CRC recurrence and death from all causes, after controlling for covariates.

RESULTS

Disease-free survival (DFS) among CRC patients was significantly worsened among patients with a high processed meat dietary pattern (the highest vs the lowest quartile HR 1.82, 95% CI 1.07 to 3.09). No associations were observed with the prudent vegetable or the high-sugar patterns and DFS. The association between the processed meat pattern and DFS was restricted to patients diagnosed with colon cancer (the highest vs the lowest quartile: HR 2.29, 95% CI 1.19 to 4.40) whereas the relationship between overall survival (OS) and this pattern was observed among patients with colon cancer only (the highest vs the lowest quartile: HR 2.13, 95% CI 1.03 to 4.43). Potential effect modification was noted for sex (p value for interaction 0.04, HR 3.85 for women and 1.22 for men).

CONCLUSIONS

The processed meat dietary pattern prior to diagnosis is associated with higher risk of tumour recurrence, metastasis and death among patients with CRC.