Association between dietary fibre intake with cancer and all-cause mortality among 15 740 adults: the National Health and Nutrition Examination Survey III

Total and different dietary fiber subtypes and the risk of all-cause, cardiovascular, and cancer mortality: a dose-response meta-analysis of prospective cohort studies

We aimed to conduct a comprehensive review of the association between dietary fiber and the risk of mortality. We did a systematic search in PubMed, Scopus, and Web of Science up to November 2022 to find prospective cohort studies of the relationship between total and subtypes of dietary fiber and the risk of all-cause, cardiovascular (CVD), and cancer mortality in the general population. The hazard ratios (HRs) and 95% CIs were calculated using a random-effects model. A total of 28 studies with 1 613 885 participants were included. Higher intake of total and subtypes of dietary fiber including cereal, vegetable, legume, soluble, and insoluble fiber, but not fruit fiber, was associated with a lower risk of all-cause mortality, with HRs ranging from 0.77 for insoluble fiber to 0.93 for legume fiber. Similar findings were observed for CVD mortality, where higher intake of total and all subtypes of dietary fiber was each associated with a lower risk. Higher intake of total, cereal, vegetable, and insoluble fiber was also associated with a lower risk of cancer mortality. No association was found between the intake of fruit, legume, and soluble fiber and cancer mortality. Dose-response meta-analyses suggested an inverse association between total fiber intake and the risk of all-cause, CVD, and cancer mortality. The certainty of evidence was rated moderate for the association of total fiber with all-cause, CVD, and cancer mortality. In conclusion, our findings highlight the potential advantages of consuming a wide range of dietary fiber subtypes against all-cause, CVD, and cancer mortality. Registry and registry number: PROSPERO (CRD42021226816).

Dietary intake of total vegetable, fruit, cereal, soluble and insoluble fiber and risk of all-cause, cardiovascular, and cancer mortality: systematic review and dose-response meta-analysis of prospective cohort studies

Objectives

To conduct a systematic review and meta-analysis of prospective cohort studies to investigate the association between total, vegetable, fruit, cereal, soluble and insoluble fiber intake and risk of all causes, cardiovascular disease (CVD), and cancer mortality and quantitatively assess the dose-response relation.

Methods

Eligible studies were identified by searching PubMed, Embase and Web of science before August 2023. Random effects models were used to calculate summary relative risk (RR) and 95% confidence intervals (CI) and restricted cubic splines to model the linear/non-linear association.

Results

The summary RR for all-cause, CVD and cancer mortality of dietary fiber was 0.90 (95% CI: 0.86,0.93), 0.87 (0.84,0.91), 0.91 (0.88,0.93), respectively. Significant association was observed for all-cause and CVD mortality with fruit, vegetable cereal and soluble fiber intake and cancer mortality with cereal fiber intake. No significant association was found for insoluble fiber, vegetable or fruit fiber intake and cancer mortality. Dose-response analysis showed a significant non-linear relation of dietary fiber intake with all-cause mortality, and linear relation for others.

Conclusions

Higher dietary fiber including different type and food sources of fiber intake were associated with lower risk of mortality. Our findings provide more comprehensive evidence on dietary fiber intake with mortality.

Systematic review registration

https://www.crd.york.ac.uk/prospero, identifier: CRD42022338837.

The Ideal Diet for Humans to Sustainably Feed the Growing Population - Review, Meta-Analyses, and Policies for Change

INTRODUCTION

As of now, no study has combined research from different sciences to determine the most suitable diet for humans. This issue is urgent due to the predicted population growth, the effect of this on the environment, and the deterioration of human health and associated costs.

METHODS

A literature review determined whether an optimal diet for humans exists and what such a diet is, followed by six meta-analyses. The standard criteria for conducting meta-analyses of observational studies were followed. A review of literature reporting Hazard Ratios with a 95% confidence interval for red meat intake, dairy intake, plant-based diet, fiber intake, and serum IGF-1 levels were extracted to calculate effect sizes.

RESULTS

Results calculated using NCSS software show that high meat consumption increases mortality probability by 18% on average and increases diabetes risk by 50%. Plant-based and high-fiber diets decrease mortality by 15% and 20% respectively ( p < .001). Plant-based diets decreased diabetes risk by 27%, and dairy consumption (measured by increased IGF-1 levels) increased cancer probability by 48% ( p < 0.01). A vegetarian or Mediterranean diet was not found to decrease the probability of heart disease. A vegetarian diet can be healthy or not, depending on the foods consumed. A Mediterranean diet with high quantities of meat and dairy products will not produce the health effects desired. The main limitations of the study were that observational studies were heterogeneous and limited by potential confounders.

DISCUSSION

The literature and meta-analyses point to an optimal diet for humans that has followed our species from the beginnings of humankind. The optimal diet is a whole food, high fiber, low-fat, 90+% plant-based diet. This diet allowed humans to become the most developed species on Earth. To ensure people's nutritional needs are met healthily and sustainably, governmental dietary interventions are necessary.

Soluble and Insoluble Dietary Fiber Consumption and Colorectal Cancer Risk: A Systematic Review and Meta-Analysis

Colorectal cancer (CRC) is the third most common cancer worldwide with a high mortality rate. Dietary fibers, both soluble and insoluble, are essential for reducing the risk of CRC. In this study, a meta-analysis was performed to examine the relationship between the soluble and insoluble dietary fiber consumption and CRC risk. The highest vs. lowest fiber concentrations were compared by using PRISMA guidelines. To determine publishing bias, the Egger test; assess study heterogeneity I² statistics were used. Studies that reported adjusted relative risk estimates with 95% confidence intervals (Cl) for the associations of interest were included. The results reveal that the relationship between soluble and insoluble fiber intake and the risk of CRC is almost equal [The total fiber ES = 0.75 (95% CI = 0.66-0.86), soluble fiber ES = 0.78 (95% CI = 0.66-0.92), insoluble fiber ES = 0.77 (95% CI = 0.67-0.88)]. Funnel plot and Egger's linear regression tests demonstrated that there was no publication bias. Both soluble and insoluble fiber consumption appear to be protective against CRC, with a clinically significant reduction in CRC risk. It is critical to identify preventive steps to avoid the CRC development, especially by leading a healthier lifestyle that includes healthy diet.

Model with the GBDT for Colorectal Adenoma Risk Diagnosis

Background and Objective:

Colorectal cancer (CRC) is a common malignant tumor of the digestive system; it is associated with high morbidity and mortality. However, an early prediction of colorectal adenoma (CRA) that is a precancerous disease of most CRC patients provides an opportunity to make an appropriate strategy for prevention, early diagnosis and treatment. It has been aimed to develop a machine learning model to predict CRA that could assist physicians in classifying high-risk patients, make informed choices and prevent CRC.

Methods:

Patients who had undergone a colonoscopy to fill out a questionnaire at the Sixth People Hospital of Shanghai in China from July 2018 to November 2018 were instructed. A classification model with the gradient boosting decision tree (GBDT) was developed to predict CRA. This model was compared with three other models, namely, random forest (RF), support vector machine (SVM), and logistic regression (LR). The area under the receiver operating characteristic curve (AUC) was used to evaluate performance of the models.

Results:

Among the 245 included patients, 65 patients had CRA. The area under the receiver operating characteristic (AUCs) of GBDT, RF, SVM ,and LR with 10 fold-cross validation was 0.8131, 0.74, 0.769 and 0.763. An online prediction service, CRA Inference System, to substantialize the proposed solution for patients with CRA was also built.

Conclusion:

Four classification models for CRA prediction were developed and compared, and the GBDT model showed the highest performance. Implementing a GBDT model for screening can reduce the cost of time and money and help physicians identify high-risk groups for primary prevention.

StudentKost: a cross-sectional study assessing college students' diets: reason for concern?

College students constitute a significant proportion of the young adult population in Norway. They are in their reproductive years, which is of interest regarding diet and preconception health. Our objective was to assess young college students' diet and nutrient intake in relation to national dietary recommendations and assess the probability of inadequate micronutrient intake for both genders using the Nordic Nutrition Recommendations, and also to evaluate its consequences on preconception health and create a groundwork for future interventions on this group. At the University of Agder (UiA), we enrolled 622 students aged 18-40 years for a cross-sectional study of student's diet, StudentKost. The students completed a food frequency questionnaire, including questions of supplement use, over the past 4 weeks. Intake of fruits, vegetables, oily fish, and whole grain was lower than recommended, as were mean intake of folate, iron, and iodine. Our main findings are that students have a somewhat suboptimal diet compared to the Norwegian dietary guidelines. Male students had generally lower diet quality than females. Compared to the Nordic Nutrition Recommendations (NNR), we also saw a relatively high probability of inadequate intake of several micronutrients and a very high probability for some micronutrients in a significant portion of the sample. Public health effort should be directed towards improving students and young adults' diet in general, and interventions towards improving preconception health should be explored. The low participation rate limits the generalizability of our findings. Our findings encourage further investigation into young adults' diet.

The Association between Prebiotic Fiber Supplement Use and Colorectal Cancer Risk and Mortality in the Women's Health Initiative

BACKGROUND

Fiber-based prebiotic supplements are marketed for maintaining bowel health and promoting beneficial gut bacteria. However, the association between prebiotic supplement use and colorectal cancer risk and mortality is unknown.

METHODS

The association between prebiotic use and colorectal cancer risk and mortality was evaluated in postmenopausal women in the Women's Health Initiative study. Self-reported prebiotic use was documented at study enrollment. Adjudicated colorectal cancer cases and mortality were captured using medical and death records. Cox proportional hazards models were used to estimate the HR related to prebiotic use and colorectal cancer risk and mortality.

RESULTS

In total, 3,032 colorectal cancer cases were diagnosed during an average 15.4 years of follow-up. Overall, 3.7% of women used a prebiotic with psyllium, the major fiber type. Use of any prebiotic supplement was not associated with colorectal cancer risk or mortality. The type of prebiotic supplement (none vs. insoluble or soluble) was not associated with colorectal cancer risk; however, use of insoluble fiber prebiotics compared with none was associated with higher colorectal cancer mortality [HR, 2.79; 95% confidence interval (CI), 1.32-5.90; P = 0.007]. Likelihood ratio tests indicated no significant interactions between prebiotic use and other colorectal cancer risk factors, including metabolic syndrome.

CONCLUSIONS

Prebiotic fiber supplement use was not associated with colorectal cancer risk. Insoluble, but not soluble, prebiotic fiber use was associated with higher colorectal cancer mortality. These findings do not support the promotion of prebiotic fiber supplements to reduce colorectal cancer risk or colorectal cancer mortality.

IMPACT

Further investigation is warranted for findings regarding insoluble prebiotic fiber and higher colorectal cancer mortality in postmenopausal women.

Lifestyle Management of Diabetes: Implications for the Bone-Vascular Axis

PURPOSE OF REVIEW

To describe the main pathways involved in the interplay between bone and cardiovascular disease and to highlight the possible impact of physical activity and medical nutrition therapy on the bone-vascular axis.

RECENT FINDINGS

Diabetes increases the risk of both cardiovascular disease and bone fragility fractures, sharing common pathogenic pathways, including OPG/RANK/RANKL, the FGF23/Klotho axis, calciotropic hormones, and circulating osteogenic cells. This may offer new therapeutic targets for future treatment strategies. As lifestyle intervention is the cornerstone of diabetes treatment, there is potential for an impact on the bone-vascular axis. Evidence published suggests the bone-vascular axis encompasses key pathways for cardiovascular disease. This, along with studies showing physical activity plays a crucial role in the prevention of both bone fragility and cardiovascular disease, suggests that lifestyle intervention incorporating exercise and diet may be helpful in managing skeletal health decline in diabetes. Studies investigating the controversial role of high-fiber diet and dietary vitamin D/calcium on bone and cardiovascular health suggest an overall benefit, but further investigations are needed in this regard.

Progress in primary prevention of colorectal cancer

Colorectal cancer (CRC) is one of the most common malignant tumors in the digestive tract, with high incidence and mortality. Most of CRC cases are diagnosed at the late stage, and the treatment effect is therefore poor. Thus, the prevention of CRC is particularly important. There have been many studies on the prevention of CRC in recent years. This paper will summarize the latest research on the primary prevention of CRC.