• cancer
• gastroenterology
• risk factors

• Humans
• Colorectal Neoplasms/epidemiology
• Colorectal Neoplasms/genetics
• Colorectal Neoplasms/diagnosis
• Risk Factors
• Risk Assessment

• Animals
• Diet/adverse effects
• Vegetables
• Vitamins
• Colorectal Neoplasms/etiology
• Colorectal Neoplasms/prevention & control
• Colorectal Neoplasms/epidemiology
• Eating

• Colorectal cancer
• Dietary patterns
• Processed diet
• Prudent diet
• Western diet

• 203/PPSK/6720021, LRGS/MRUN/FI/02/2018/01, and LR001-2019 Long-Term Research Grant Scheme (LRGS)-Malaysia Research University Network (MRUN)
• 203/PPSK/6720021, LRGS/MRUN/FI/02/2018/01, and LR001-2019 Long-Term Research Grant Scheme (LRGS)-Malaysia Research University Network (MRUN)
• 203/PPSK/6720021, LRGS/MRUN/FI/02/2018/01, and LR001-2019 Long-Term Research Grant Scheme (LRGS)-Malaysia Research University Network (MRUN)
• 203/PPSK/6720021, LRGS/MRUN/FI/02/2018/01, and LR001-2019 Long-Term Research Grant Scheme (LRGS)-Malaysia Research University Network (MRUN)
• 203/PPSK/6720021, LRGS/MRUN/FI/02/2018/01, and LR001-2019 Long-Term Research Grant Scheme (LRGS)-Malaysia Research University Network (MRUN)
• 203/PPSK/6720021, LRGS/MRUN/FI/02/2018/01, and LR001-2019 Long-Term Research Grant Scheme (LRGS)-Malaysia Research University Network (MRUN)
• 203/PPSK/6720021, LRGS/MRUN/FI/02/2018/01, and LR001-2019 Long-Term Research Grant Scheme (LRGS)-Malaysia Research University Network (MRUN)

• CRC/EMRO
• Colorectal cancer
• meta-analysis
• risk factor
• smoking
• systematic review

• Humans
• Smoking/adverse effects
• Smoking/epidemiology
• Colorectal Neoplasms/epidemiology
• Colorectal Neoplasms/etiology

• Asia
• colorectal neoplasms
• diet
• dietary exposure

Multiple studies investigating the relationship between intake of different types of fruit and colorectal cancer (CRC) risk have yielded inconsistent results.

To perform a meta-analysis of existing studies to assess the association between the intake of different kinds of fruit and the incidence of CRC.

We searched online literature databases including PubMed, Embase, WOS, and Cochrane Library for relevant articles available up to August 2022. With data extracted from observational studies, odds ratios (ORs) with 95% confidence intervals (CIs) were assessed using random-effects models. A funnel plot and Egger’s test were used to determine publication bias. Furthermore, subgroup analysis and dose-response analysis were performed. All analyses were conducted using R (version 4.1.3).

Twenty-four eligible studies involving 1068158 participants were included in this review. The meta-analysis showed that compared to a low intake, a higher intake of citrus, apples, watermelon, and kiwi reduced the risk of CRC by 9% [OR (95%CI) = 0.91 (0.85-0.97)], 25% [OR (95%CI) = 0.75 (0.66-0.85)], 26% [OR (95%CI) = 0.74 (0.58-0.94)], 13% [OR (95%CI) = 0.87 (0.78-0.96)], respectively. No significant association was observed between the intake of other types of fruit and the risk of CRC. In the dose-response analysis, a nonlinear association was found [R (95%CI) = -0.0031 (-0.0047 to -0.0014)] between citrus intake and CRC risk (P < 0.001), with the risk minimized around 120 g/d (OR = 0.85), while no significant dose-response correlation was observed after continued increase in intake.

We found that a higher intake of citrus, apples, watermelon, and kiwi was negatively associated with the risk of CRC, while the intake of other types of fruits were not significantly associated with CRC. Citrus intake showed a non-linear dose-response relationship with the risk of CRC. This meta-analysis provides further evidence that a higher intake of specific types of fruit is effective in preventing the occurrence of CRC.

• Colorectal cancer
• Fruit
• Dose
• Systematic review
• Meta-analysis

• Fruit
• Diet/adverse effects
• Risk Factors
• Citrus
• Colorectal Neoplasms/epidemiology
• Colorectal Neoplasms/prevention & control

• 24-hour dietary recall
• adolescents
• adults
• children
• food consumption
• household
• obesity
• older adults
• overweight

• Colorectal neoplasms
• Cooking method
• Eating
• Feeding behavior

• Colorectal cancer
• Legumes
• Meta-analysis
• Nuts

Personalized nutrition and protective diets and lifestyles represent a key cancer research priority. The association between consumption of specific dietary components and colorectal cancer (CRC) incidence has been evaluated by a number of population-based studies, which have identified certain food items as having protective potential, though the findings have been inconsistent. Herein we present a systematic review and meta-analysis on the potential protective role of five common phytochemically rich dietary components (nuts, cruciferous vegetables, citrus fruits, garlic and tomatoes) in reducing CRC risk.

To investigate the independent impact of increased intake of specific dietary constituents on CRC risk in the general population.

Medline and Embase were systematically searched, from time of database inception to January 31, 2020, for observational studies reporting CRC incidence relative to intake of one or more of nuts, cruciferous vegetables, citrus fruits, garlic and/or tomatoes in the general population. Data were extracted by two independent reviewers and analyzed in accordance with the Meta-analysis of Observational Studies in Epidemiology (MOOSE) and Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) reporting guidelines and according to predefined inclusion/exclusion criteria. Effect sizes of studies were pooled using a random-effects model.

Forty-six studies were identified. CRC risk was significantly reduced in patients with higher vs lower consumption of cruciferous vegetables [odds ratio (OR) = 0.90; 95% confidence interval (CI): 0.85-0.95; P < 0.005], citrus fruits (OR = 0.90; 95%CI: 0.84-0.96; P < 0.005), garlic (OR = 0.83; 95%CI: 0.76-0.91; P < 0.005) and tomatoes (OR = 0.89; 95%CI: 0.84-0.95; P < 0.005). Subgroup analysis showed that this association sustained when looking at case-control studies alone, for all of these four food items, but no significant difference was found in analysis of cohort studies alone. Nut consumption exhibited a similar trend, but overall results were not significant (OR = 0.72; 95%CI: 0.50-1.03; P < 0.07; I² = 90.70%). Putative anticarcinogenic mechanisms are proposed using gene-set enrichment analysis of gene/protein perturbations caused by active compounds within each food item.

Increased cruciferous vegetable, garlic, citrus fruit and tomato consumption are all inversely associated with CRC risk. These findings highlight the potential for developing precision nutrition strategies for CRC prevention.

• Colorectal cancer
• Disease prevention
• Diet
• Risk
• Nutrigenomics
• Meta-analysis

PubMed, Web of Science, and the Cochrane Database of Systematic Reviews were searched for meta-analyses that provided risk estimates (±95% confidence intervals) for associations between intakes of whole and refined grains and risk of total and site-specific cancer. The preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines were followed. Only meta-analyses that included whole grains and refined grains as separate food groups, and not as part of dietary patterns, were included. A total of 17 publications were identified that met inclusion criteria. Within these, results from a total of 54 distinct meta-analyses were reported for whole grains and 5 meta-analyses for refined grains. For total cancer mortality, 7 meta-analyses of cohort studies indicated that whole grain intake was associated with 6% to 12% lower risk in comparison of highest vs. lowest intake groups, and 3% to 20% lower risk for doses ranging from 15 to 90 g/day. For site-specific cancers, meta-analyses indicated that whole grain intake was consistently associated with lower risks of colorectal, colon, gastric, pancreatic, and esophageal cancers. Limited data were available for refined grains, with only 4 publications providing risk estimates, and only 1 of the meta-analyses included more than 3 studies. High intake of refined grains was associated with increased risk of colon and gastric cancer. By contrast, in the only dose-response meta-analysis, each 90 g/day consumption of refined grains was associated with a 6% lower risk of total cancer. In addition to the limited number of published meta-analyses on refined grains, results were also weakened due to the fact that refined grains were frequently defined to include both staple grain foods and indulgent grain foods, and the majority of studies included in the meta-analyses provided no specific definition of refined grains. Overall, meta-analyses of cohort and case-control studies consistently demonstrate that whole grain intake is associated with lower risk of total and site-specific cancer, and support current dietary recommendations to increase whole grain consumption. By contrast, the relationship between refined grain intake and cancer risk is inconclusive.

• case-control
• cereals
• chronic disease
• cohort
• diet
• epidemiology
• fiber
• mortality

• Colorectal cancer
• Digestive tract cancer
• Esophagus cancer
• Gastric cancer
• Meta-analysis
• Whole grains

• Gastrointestinal Neoplasms/epidemiology
• Gastrointestinal Neoplasms/prevention & control
• Humans
• Odds Ratio
• Risk Factors
• Whole Grains

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.

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.

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).

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.

• Colorectal cancer
• Literature review
• Meat
• Middle Eastern and North African countries
• Prevention
• Risk

• Morocco
• case-control study
• colorectal cancer
• diet
• study protocol

• 001 World Health Organization

• PREDIMED study
• colorectal cancer
• dairy products
• mediterranean diet
• milk

• Aged
• Aged, 80 and over
• Cardiovascular Diseases/complications
• Case-Control Studies
• Colorectal Neoplasms/epidemiology
• Colorectal Neoplasms/etiology
• Dairy Products/adverse effects
• Female
• Follow-Up Studies
• Humans
• Incidence
• Male
• Mediterranean Region/epidemiology
• Middle Aged
• Prognosis
• Prospective Studies
• Risk Factors

• Colorectal cancer
• Dairy products
• Middle eastern and north African countries
• Prevention
• Risk
• Systematic review

• Case-control study
• colorectal cancer
• fat
• meat
• milk
• oils
• processed meat