Nutrition reviews最新文献

Context: Telomeres maintain chromosome stability and mark cellular aging, and their shortening with age compromises genomic stability.

Objective: The purpose of this study was to conduct a meta-analysis of existing evidence to evaluate the relationship between the maternal pregnancy body mass index (BMI) and children's telomere length (TL).

Data source: Web of Science, Scopus, and PubMed databases were systematically searched from their inception to August 27, 2023, for pertinent observational studies.

Data extraction: The random-effects meta-analysis was conducted on eligible studies that investigated the linear relationship between exposure and the outcomes of interest, utilizing the reported β-coefficient. Cochran's Q test and I2 statistics were used to assess heterogeneity.

Data analysis: A significant association was observed between maternal pregnancy BMI and children's TL (32 studies, pooled effect size [ES]: -0.04; 95% CI: -0.06 to -0.01; I2 = 47.51%, P < .001) and maternal prepregnancy BMI and children's TL at birth (16 studies; pooled ES: -0.05; 95% CI: -0.08 to -0.02; I2 = 53.49%, P < .001).

Conclusion: The findings indicate an inverse association between maternal prepregnancy BMI and TL in infants, which is evident within the normal to obese BMI range. This underscores the significance of maternal weight status before pregnancy as a determinant of offspring TL.

Systematic review registration: PROSPERO registration no. CRD42023466425.

Context: Chronic kidney disease (CKD) stands out as one of the most widespread diseases globally. Dietary interventions, such as adopting a low-protein diet (LPD), play a crucial role as a key approach in impeding the advancement of CKD.

Objective: The objective of this umbrella review was to provide understanding into the effects of an LPD on kidney function among individuals with CKD, along with evaluating the certainty of the available evidence.

Data sources: Searches for relevant studies were conducted without limitations through databases such as PubMed, Scopus, Web of Science, and Google Scholar, encompassing findings up to June 2023.

Data extraction: The effect sizes for each meta-analysis were recalibrated using a random-effects model. The certainty of the evidence was evaluated using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach.

Data analysis: Twenty-five meta-analyses including 47 randomized controlled trials were included in this study. Moderate certainty of the evidence suggests that LPDs may reduce glycated hemoglobin (HbA1c) and phosphorus levels, and the risk of progressing to end-stage renal disease in patients with CKD. Moreover, notable outcomes include increased glomerular filtration rate and decreased levels of serum albumin, blood urea nitrogen, and bicarbonate, although the certainty of evidence is low. In addition, LPDs can substantially decrease proteinuria, urine urea, and parathyroid hormone (PTH), although with very low certainty. The effects on serum creatinine, calcium, systolic blood pressure, and diastolic blood pressure are statistically nonsignificant, with the certainty of evidence ranging from low to moderate.

Conclusion: LPDs demonstrated beneficial effects on renal function in patients with CKD, which is supported by moderate to very low certainty evidence.

Systematic review registration: PROSPERO registration no. CRD42023473647.

Rice is a global staple food crop for nearly half of the world's population. Rice bran along with the germ are essential components of whole-grain rice and have immense potential for enhancing human nutrition. Rice bran has a unique composition and distinct requirements for processing before it can be consumed by humans when compared with other cereal brans. The comprehensive overview and synthesis of rice bran processing include extending the shelf life for functional food product development and extraction of bioactive components. This narrative review highlights established and innovative stabilization approaches, including solvent extraction and enzymatic treatments, which are critical methods and technologies for wider rice bran availability. The nutrient and phytochemical profiles of rice bran may improve with new cultivar development and food-fortification strategies. The postharvest agricultural practices and processing techniques can reduce food waste while also supporting growers to produce novel pigmented cultivars that can enhance nutritional value for human health.

Context: Clinical investigation has shown that the addition of saffron or crocin to standard antidiabetic medications improves a patient's metabolic profile, oxidative stress (OS), and inflammatory response. Despite a large number of studies examining the impact of saffron supplementation on OS, inflammation, and renal and liver function parameters, no systematic review or meta-analysis has been conducted to compile the outcomes in patients with type 2 diabetes mellitus (T2DM).

Objective: The current systematic review and meta-analysis was performed to investigate the effect of saffron or crocin intake on OS, inflammation, and renal and liver function parameters in patients with T2DM.

Data sources: Online databases including PubMed, Scopus, ISI Web of Science, and Cochrane Library were searched up to December 2023.

Data extraction: The mean differences and their respective SDs were extracted. Using a random-effects model, the pooled data were calculated as standardized mean difference (SMD) with 95% CI.

Data analysis: 17 eligible randomized controlled trials were included in this meta-analysis. The pooled findings showed that saffron supplementation remarkably decreased the levels of tumor necrosis factor-α (SMD: -0.37; 95% CI: -0.69 to -0.05; I2 = 40.77%, P = .15), interleukin-6 (IL-6) (SMD: -0.38; 95% CI: -0.65 to -0.10; I2 = 0%, P = .68), and malondialdehyde (MDA) (SMD: -0.36; 95% CI: -0.65 to -0.07; I2= 20.51%, P = .02) compared with the control. In addition, based on subgroup analyses, taking ≥100 mg of saffron daily in individuals with T2DM reduced the serum levels of IL-6 (SMD: -0.50; 95% CI: -0.90 to -0.10; I2 = 0%, P = .50) and MDA (SMD: -0.36; 95% CI: -0.68 to -0.03; I2 = 0, P = .97). Furthermore, the level of alanine transaminase was decreased (SMD: -0.43; 95% CI: -0.73 to -0.12; I2 = 0, P = .66) with a treatment period of <60 days of saffron or crocin supplementation.

Conclusion: Larger studies with more follow-up and higher doses of both saffron and crocin are needed in order to understand the efficacy and safety of these herbs for long-term use as routine therapies.

Systematic review registration: PROSPERO registration no. CRD42023458119.

Type 2 diabetes mellitus (T2DM) and progressive liver disease are 2 of the most significant global health concerns, and they have alarming and ever-increasing prevalence. A growing body of literature has demonstrated a potential multilateral link between gut microbiome dysbiosis and the development and progression of the above-mentioned conditions. Modulation of gut microbial composition from the norm is due to changes in diet allied with external factors such as age, genetics, and environmental changes. In this comprehensive review, we recapitulate the research to date investigating the links between gut microbiome dysbiosis and T2DM or liver disease, with special attention to the importance of diet. Additionally, we review the most commonly used tools and methodologies of investigating changes in the gut microbiome, highlighting the advantages and limitations of each strategy, before introducing a novel in vitro approach to the problem. Finally, the review offers recommendations for future research in this field that will allow better understanding of how the gut microbiota affects disease progression and of the prospects for intestinal microbiota-based therapeutic options.

Context: There are contradictory results regarding the relationship between dietary intakes of monounsaturated fatty acids (MUFAs) and risk of stroke.

Objective: The purpose of this study was to review the existing body of research on the relationship between MUFA consumption and stroke risk through a systematic review and meta-analysis.

Data source: PubMed, Scopus, and ISI Web of Science were all systematically searched up to January 2023.

Data extraction: A total of 11 prospective cohort studies that investigated MUFA consumption in relation to stroke risk were included.

Data analysis: Relative risk (RR) and 95% CIs for the highest vs lowest category of dietary MUFA intake were combined using a random-effects model. Linear and nonlinear dose-response relations were assessed through 1-stage weighted mixed-effects meta-analysis. These studies included 475 207 participants and 8438 cases. In highest vs lowest consumption analysis, MUFA intake was inversely associated with total stroke (RR: 0.80; 95% CI: 0.67, 0.96; I2 =65.2%, Q-test P = .001; n = 11) and hemorrhagic stroke (RR: 0.80; 95% CI: 0.68, 0.95; I2 = 0.0%, Q-test P = .77; n = 5) risk. Conversely, this association was not significant for ischemic stroke (RR: 0.86; 95% CI: 0.69, 1.07; I2 =62.3%, Q-test P = .01; n = 8). An inverse association was observed between each 10-g/d MUFA intake and hemorrhagic stroke (RR: 0.79; 95% CI: 0.65, 0.96) but not total and ischemic stroke. We did not find any evidence for a nonlinear association between MUFA intake and total stroke and its subtypes.

Conclusion: This meta-analysis shows that higher MUFA intake could lower the risk of total and hemorrhagic, but not ischemic, stroke. This could be important for public health.

Systematic review registration: PROSPERO registration no. CRD42023458555.

Context: Previous reviews have focused on the effects of probiotics on colitis, but there is a need to understand their impact on barrier integrity and tight junction protein improvement in colitis.

Objective: This study aimed to systematically examine the effects of probiotic use on barrier integrity in colitis disease. This study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

Data sources: A systematic search in PubMed, Web of Science, Scopus, and Cochrane databases identified 2537 articles.

Data extraction: As a result of the search, 2537 articles were accessed. Study results were summarized descriptively through discussions by intervention conditions, study population, measurement methods, and key findings. The included studies were independently reviewed and all authors reached consensus on the quality and major findings from the included articles. Forty-six studies that met the inclusion criteria were analyzed within the scope of the systematic review.

Results: Although the study primarily utilized probiotics from the Lactobacillaceae family (notably, L casei, L reuteri, L rhamnosus, L plantarum, and L pentosus) and the Bifidobacteriaceae family (notably, B breve, B animalis, and B dentium), other probiotics also demonstrated positive effects on tight junction proteins. These effects are attributed to the production of bioactive and metabolic compounds, as well as short-chain fatty acids, which combat pathogens and reduce anti-inflammatory agents. However, it was observed that the effects of these probiotics on tight junction proteins varied depending on the strain and dose.

Conclusion: The beneficial effects of probiotics on remission in inflammatory bowel disease are well documented. Studies show that probiotics generally improve intestinal barrier function, but factors such as dose, duration, and bacterial species combinations need further clarification. Additionally, comprehensive studies are needed to understand how improved barrier function affects absorption in individuals.

Systematic review registration: PROSPERO registration no. CRD42023452774.

Context: Sarcopenia and cachexia lead to muscle wasting and increased health risks in older adults. Both sarcopenia and cachexia are associated with inflammaging, a chronic low-grade inflammatory state linked to aging. Strategies to preserve muscle mass and function are crucial for maintaining independence and quality of life among the elderly.

Objective: This meta-analysis and systematic review was conducted to comprehensively assess the individual and combined effects of exercise training and protein supplementation on circulatory markers of inflammation in older adults.

Data sources: A systematic search of the PubMed, Scopus, Cochrane CENTRAL, and SPORTDiscus databases was conducted to identify relevant studies published until January 2024.

Data extraction: The search focused on randomized controlled trials examining the impact of exercise training (Ex), protein consumption (Pro), or their combination (Ex-Pro) on inflammatory factors, including C-reactive protein (CRP), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) compared with a control (Con).

Data analysis: The meta-analysis revealed a significant decrease in CRP levels in the Ex vs Pro (P = .0003) and the Ex-Pro (P < .00001) group compared with the Ex group and in overall experimental (EXPL) subgroups (P = .0002) compared with the Con group. A similar reduction was found in IL-6 in the Ex group (P = .001), Ex-Pro group (P = .05), and EXPL (P = .0002) subgroup compared with the Pro group. However, for TNF-α levels, a significant reduction was noted only in the Ex-Pro group compared with the Ex group (P < .00001).

Conclusion: Exercise training and protein supplementation, particularly when combined, show greater benefits in mitigating inflammaging. These findings highlight the importance of combined interventions against muscle wasting. Future studies and meta-analyses should further address the effects of Ex and Pro and Ex-Pro on inflammatory markers of older adults, considering specific conditions and larger sample sizes to identify optimal strategies for the aging population.