Dietary fiber, glycemic index, glycemic load and renal cell carcinoma risk

In Vivo Glycemic Response of Fruit-Based Mango (Mangifera indica) and Pineapple (Ananas comosus) Bars in In Vitro and In Silico Enzyme Inhibitory Effects Studies

The habitual consumption of snacks has the potential to enrich or harm the diet. They can contribute to excessive caloric intake and hyperglycemia. Thus, there is an increasing interest in snacks with health-promoting properties. This study aimed to demonstrate the beneficial effect of two fruit-based bars on glucose levels through in vitro, in vivo, and in silico assays. Mango (Mangifera indica L.) and pineapple (Ananas comosus L.) bars (MB and PB) were prepared, and chemical composition, postprandial glycemic response, glycemic index (GI), and glycemic load (GL) were evaluated. The inhibitory effect of fruit bar extracts on α-amylase and α-glucosidase activity and their respective molecular docking was assessed. MB and PB showed the lowest postprandial glycemic response vs. the control bar (p < 0.005), a lower GI (CB: 64.20, PB: 53.20, MB: 40.40), and a GL of 10.9 (CB), 7.9 (PB), and 6.1 (MB), (p < 0.05). MB and PB showed the highest inhibition % of α-amylase (61.44 and 59.37%, respectively) and α-glucosidase (64.97 and 64.57%). Naringenin (-1692.5985 and -2757.674 kcal/mol) and ferulic acid (-1692.8904 and -2760.3513 kcal/mol) exhibited more favorable interaction energies against α-amylase and α-glucosidase activity. The presence of polyphenols from the fruit influenced enzymatic inhibition. Likewise, the dietary fiber in the bars evaluated allowed us to observe a positive effect that favors glycemic control, making them a healthy alternative for snacking.

Kidney Cancer Integrative Oncology: Possible Options for Care

PURPOSE OF REVIEW

This study aims to review how complementary and integrative medicine (CIM), defined as therapies utilizing nutrition, physical activity, herbs, supplements, mind-body therapies, homeopathy, and other non-traditional therapies, can address the prevention, treatment, side effects, and recurrence of kidney cancer. This review discusses advances and discoveries in research, gaps in research, current debates on the subject, and directions for future research. We queried Ovid MEDLINE and PubMed databases using the search terms kidney cancer, integrative medicine, integrative oncology, nutrition, supplements, treatment, prevention, and therapy. Searches were limited to integrative medicine and integrative oncology. We reviewed CIM therapies related to prevention, treatment, side effect mitigation, and recurrence of kidney cancers.

RECENT FINDINGS

Search results yielded 211 studies, of which 87 were relevant to this review. Studies related to CIM and kidney cancer were clustered into themes, including nutrition, physical activity, supplements, mind-body therapies, and alternative therapies. This review provides a foundation for utilizing the principles of integrative medicine in the prevention of and care for patients with kidney cancer and the need for further focused research on the effectiveness of CIM in kidney cancers.

Dietary glycemic index, glycemic load, and renal cancer risk: findings from prostate, lung, colorectal, and ovarian cancer trial

Background

Dietary glycemic index (GI) or glycemic load (GL) has been associated with the development of many cancers, but the evidence for renal cancer is still limited. The aim of the present study was to investigate the association between GI or GL and renal cancer risk in the Prostate, Lung, Colorectal, and Ovarian Cancer (PLCO) Screening Trial.

Methods

The cohort for our analysis consisted of 101,190 participants. GI and GL were calculated from the FFQ data using previously published reference values. Multivariate-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox regression model after adjusting for most known renal cancer risk factors.

Results

During a median of 12.2 years of follow-up, 443 incident renal cancer cases occurred. Higher dietary GI was significantly associated with a higher risk of renal cancer (HR_Q3vsQ1: 1.38; 95% CI: 1.09-1.74; p for trend = 0.008). There was no significant association between dietary GL and renal cancer risk (HR_Q3vsQ1 = 1.12, 95% CI = 0.79-1.59, p for trend = 0.591). Spline regression plot revealed a higher risk of renal cancer with a higher GI but not GL. There was no statistical evidence for nonlinearity (p for nonlinearity >0.05).

Conclusion

In summary, findings of this large-scale prospective cohort study suggested that dietary GI may be associated with the risk of renal cancer. If confirmed in other populations and settings, dietary GI could be considered as a modifiable risk factor for renal cancer prevention.

Associations between dietary fiber intake and mortality from all causes, cardiovascular disease and cancer: a prospective study

OBJECTIVE

Several studies suggest that dietary fiber intake may reduce mortality risk, but this might depend on the fiber types and the evidence regarding the role of soluble fiber or insoluble fiber on death risk remain limited and inconsistent. Therefore, this study aimed to comprehensively evaluate multiple types of dietary fiber intake on mortality from all causes, cardiovascular disease and cancer in the large-scale Prostate, Lung, Colorectal, and Ovarian Cancer (PLCO) Screening Trial.

METHODS

A multivariate Cox proportional hazards model was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

This study finally included 86,642 participants with 17,536 all-cause deaths, 4842 cardiovascular deaths and 5760 cancer deaths identified after a total of 1,444,068 follow-up years. After adjusting for potential confounders, dietary total fiber intake was statistically significantly inversely associated with all-cause death (Q5 vs Q1: HR 0.71, 95% CI 0.66-0.75; P for trend < 0.001), cardiovascular death (Q5 vs Q1: HR 0.73, 95% CI 0.65-0.83; P for trend < 0.001) and cancer mortality (Q5 vs Q1: HR 0.77, 95% CI 0.69-0.86; P for trend < 0.001). Similar results were observed for both insoluble and soluble fiber intake. Restricted cubic spline model analysis suggested that there was a nonlinear association of dietary fiber intake with mortality risk (all P for nonlinearity < 0.05).

CONCLUSIONS

In this large nationally representative sample of US adult population, intakes of total fiber, soluble fiber, and insoluble fiber were associated with lower risks of all-cause, cardiovascular and cancer mortality.

Namco: a microbiome explorer

16S rRNA gene profiling is currently the most widely used technique in microbiome research and allows the study of microbial diversity, taxonomic profiling, phylogenetics, functional and network analysis. While a plethora of tools have been developed for the analysis of 16S rRNA gene data, only a few platforms offer a user-friendly interface and none comprehensively covers the whole analysis pipeline from raw data processing down to complex analysis. We introduce Namco, an R shiny application that offers a streamlined interface and serves as a one-stop solution for microbiome analysis. We demonstrate Namco's capabilities by studying the association between a rich fibre diet and the gut microbiota composition. Namco helped to prove the hypothesis that butyrate-producing bacteria are prompted by fibre-enriched intervention. Namco provides a broad range of features from raw data processing and basic statistics down to machine learning and network analysis, thus covering complex data analysis tasks that are not comprehensively covered elsewhere. Namco is freely available at https://exbio.wzw.tum.de/namco/.

The role of diet in renal cell carcinoma incidence: an umbrella review of meta-analyses of observational studies

BACKGROUND

Evidence associating diet with the incidence of renal cell carcinoma (RCC) is inconclusive. We aimed to summarize evidence associating dietary factors with RCC incidence and assess the strength and validity of this evidence.

METHODS

We conducted an umbrella review of systematic reviews or meta-analyses (SRoMAs) that assessed the association between diet and RCC incidence. Through April 2021, PubMed, Web of Science, Embase, The Cochrane Library, Scopus, and WCRF were searched. Two independent reviewers selected studies, extracted data, and appraised the quality of SRoMAs. According to credibility assessment criteria, evidence can be divided into five categories: convincing (class I), highly suggestive (class II), suggestive (class III), weak (class IV), and nonsignificant (class V).

RESULTS

Twenty-nine meta-analyses were obtained after screening. After excluding 7 overlapping meta-analyses, 22 meta-analyses including 502 individual studies and 64 summary hazard ratios for RCC incidence were included: dietary patterns or dietary quality indices (n = 6), foods (n = 13), beverages (n = 4), alcohol (n = 7), macronutrients (n =15), and micronutrients (n =19). No meta-analyses had high methodological quality. Five meta-analyses exhibited small study effects; one meta-analysis showed evidence of excess significance bias. No dietary factors showed convincing or highly suggestive evidence of association with RCC in the overall analysis. Two protective factors had suggestive evidence (vegetables (0.74, 95% confidence interval 0.63 to 0.86) and vitamin C (0.77, 0.66 to 0.90)) in overall analysis. One protective factor had convincing evidence (moderate drinking (0.77, 0.70 to 0.84)) in Europe and North America and one protective factor had highly suggestive evidence (cruciferous vegetables (0.78, 0.70 to 0.86)) in North America.

CONCLUSIONS

Although many meta-analyses have assessed associations between dietary factors and RCC, no high-quality evidence exists (classes I and II) in the overall analysis. Increased intake of vegetables and vitamin C is negatively associated with RCC risk. Moderate drinking might be beneficial for Europeans and North Americans, and cruciferous vegetables might be beneficial to North Americans, but the results should be interpreted with caution. More researches are needed in the future.

TRIAL REGISTRATION

PROSPERO CRD42021246619.

Dietary glycemic index, glycemic load and cancer risk: a meta-analysis of prospective cohort studies

PURPOSE

There is considerable inconsistency in results regarding the association of dietary glycemic index (GI) and glycemic load (GL) with cancer risk. We therefore conducted this systematic review and dose-response meta-analysis of prospective cohort studies to evaluate the relationship between dietary GI/GL and cancer risk.

METHODS

We searched PubMed and Web of Science for prospective cohort studies of dietary GI/GL in relation to risks of all types of cancer up to 31 March 2021. We used a random-effect model to calculate summary relative risks (RR) and 95% confidence intervals (CI). The certainty of evidence was assessed by the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach. This study was registered at PROSPERO (CRD42020215338).

RESULTS

Overall, 55 cohorts were included in the meta-analysis. We assessed the relationship between dietary GI or GL and risks of 23 cancer types, including hormone-related cancers, cancers from digestive system, respiratory system, urinary system and other cancer sites. High GI diet increased overall risk of cancer with low certainty of evidence (highest vs lowest categories, n = 3, RR 1.04, 95% CI 1.01-1.07). For site-specific cancers, high GI diet increased risks of lung cancer (highest vs lowest categories, n = 5, RR 1.08, 95% CI 1.01-1.18) and breast cancer (highest vs lowest categories, n = 14, RR 1.05, 95% CI 1.01-1.09), especially for postmenopausal breast cancer (highest vs lowest categories, n = 10, RR 1.06, 95% CI 1.00-1.13), all with low certainty of evidence. Additionally, dietary GI was positively related to risk of bladder cancer with low certainty of evidence (highest vs lowest categories, n = 3, RR 1.23, 95% CI 1.09-1.40), as well as negatively related to ovarian cancer risk with very low certainty of evidence (highest vs lowest categories, n = 4, RR 0.83, 95% CI 0.69-1.00) and lymphoma risk with low certainty of evidence (highest vs lowest categories, n = 2, RR 0.84, 95% CI 0.72-0.98). Besides, we found an inverse association of dietary GL with lung cancer risk with low certainty of evidence (highest vs lowest categories, n = 5, RR 0.87, 95% CI 0.80-0.94).

CONCLUSION

High dietary GI increased overall cancer risk with low certainty of evidence. For site-specific cancers, high GI diet increased the risks of breast cancer with low certainty of evidence and lung cancer with low certainty of evidence. Dietary GL was inversely associated with lung cancer risk with low certainty of evidence.

Association of Processed Meats and Alcohol Consumption with Renal Cell Carcinoma: A Worldwide Population-Based Study

The link between diet and renal cell carcinoma (RCC) is still unclear. The purpose of this study was to evaluate the association of diet with RCC's incidence and mortality rates worldwide. We conducted an ecological study including 170 countries, whose data on age-standardized (AS) incidence and mortality rates of RCC, dietary factors, and potentially confounding factors such as obesity, insufficient physical activity, tobacco smoking, hypertension, diabetes, and human development index (HDI) were collected and available on May 2020 from the Global Cancer Observatory, the Global Dietary Database, the Global Health Observatory data repository, the Diabetes Atlas 9th edition and the Human Development Report 2019. Univariable and multivariable linear regression analyses were performed to determine the association of dietary factors with incidence and mortality rates of RCC adjusted for the effects of population age and potentially confounding factors. Intake of processed meats and consumption of alcohol were both positively associated with AS incidence rates of RCC (β = 0.11, P < 0.001 and β = 0.1, P = 0.044, respectively). We suggest that high consumption of processed meats and/or alcohol is a risk factor for RCC. However, they were not associated with mortality. Further research is needed at an individual level.Supplemental data for this article is available online at https://doi.org/10.1080/01635581.2020.1856388.

Dietary glycemic index, glycemic load, and chronic disease: an umbrella review of meta-analyses of prospective cohort studies

We aimed to present a comprehensive review of the association of dietary glycemic index (GI) and load (GL) with the risk of chronic disease. Published meta-analyses of prospective observational studies evaluating the association of dietary GI and GL with risk of chronic disease were identified by a search in PubMed and Scopus to November, 2020. Summary relative risks (SRRs) were recalculated using random-effects models. The certainty of evidence was rated by the GRADE approach. Eighteen meta-analyses of prospective cohort studies, reporting 19 SRRs for dietary GI and 17 SRRs for dietary GL were identified. There was a positive association between dietary GI and the risk of type 2 diabetes, coronary heart disease, and colorectal, breast, and bladder cancers, as well as between dietary GL and the risk of coronary heart disease, type 2 diabetes, and stroke. With regard to cancers at other sites, there was no significant association. The certainty of evidence ranged from very low to low. Although by GRADE classification no associations were rated stronger than low, they were classified as one grade higher when the NutriGrade system was used. Further research is needed to add evidence for the relation of dietary GI and GL with cancer risk.

Dietary fiber intake and the risk of bladder cancer in the Prostate, Lung, Colorectal and Ovarian (PLCO) cohort

Dietary fiber intake has been implicated as a protective factor for several human cancers in multiple epidemiologic studies. However, little is known about the effect of fiber intake on bladder cancer. This study examines the association between dietary fiber intake and bladder cancer risk among participants in the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial. A total of 101 721 participants were included in this study as they completed both the baseline questionnaire and the diet history questionnaire (cancer free before completion of the diet history questionnaire). Hazard ratios (HRs) and the corresponding 95% confidence intervals (CIs) were estimated using the Cox proportional hazards regression model. After a median of 12.5 years of follow-up, 776 new cases of bladder cancer were identified. Higher intake of total fiber, insoluble fiber and soluble fiber were not significantly associated with a reduced risk of bladder cancer. The multi-adjusted HRs (95 CIs) of highest versus lowest tertile of intake were 0.83 (0.66-1.04) for total fiber (P for trend = 0.098), 0.83 (95% CI: 0.67-1.03) for insoluble fiber (P for trend = 0.092) and 0.86 (95% CI: 0.68-1.08) for soluble fiber (P for trend = 0.168), respectively. There was no significant interaction of potential confounders, including education, body mass index and smoking status, with total fiber intake on bladder cancer risk. In summary, the findings of this prospective study show that there is no obvious evidence for a link between dietary fiber consumption and bladder cancer risk. Further large cohort studies are warranted to confirm these findings.

Glycemic Index, Glycemic Load and Cancer Risk: An Updated Meta-Analysis

Diets high in glycemic index (GI) and glycemic load (GL) have been related to an increased risk of selected cancers, but additional quantification is required. We updated a systematic review and meta-analysis published in 2015 to May 2019 to provide quantitative information on GI/GL and cancer risk. Relative risks (RR) and the corresponding 95 % confidence intervals (CI) for the highest versus the lowest categories of GI and GL were extracted from selected studies and pooled using random-effects models. Twenty reports (>22,000 cancer cases) have become available after January 2015, and 15 were added to the meta-analyses by cancer sites, which considered a total of 88 investigations. The five additional reports were reviewed, but not included in the meta-analyses, since data were inadequate to be pooled. For hormone-related cancers, summary RRs for the highest versus lowest GI and GL intakes were moderately increased. They ranged from 1.04 (breast) to 1.12 (endometrium) for GI and from 1.03 (prostate) to 1.22 (ovary) for GL, of borderline significance. High GI was associated with small increased risks of colorectal (summary RR for GI: 1.20, 95% CI, 1.07–1.34—GL: 1.09, 95% CI, 0.97–1.22, 19 studies), bladder (GI: 1.25, 95% CI, 1.11–1.41—GL: 1.10, 95% CI, 0.85–1.42, four studies) and kidney cancers (GI: 1.16, 95% CI, 1.02–1.32—GL: 1.14, 95% CI, 0.81–1.60, five studies). GL was not significantly related to those cancer sites. Stomach, prostate and lung cancers were not associated with GI and GL. The present analysis, based on an updated comprehensive evaluation of the epidemiological literature, indicates moderate unfavorable effects of high versus low GI on colorectal, and possibly bladder and kidney cancers, and a possible moderate positive association between GL and endometrial cancer.