Nutrition reviews最新文献

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.

The health-promoting benefits of walnut consumption are substantially ascribed to its fatty acid (FA) profile, which is rich in polyunsaturated FA with an exceptionally high n-3 to n-6 ratio. There are also phytonutrients in walnuts that are linked to health welfare. This review article integrates all studies on the effects of walnuts on the cardiovascular system performed on experimental animals, and thus is a source of data on the mechanisms underlying the observed effects. These studies, which are very diverse in experimental design, indicate that a diet enriched with walnuts or treating animals with walnut extract or chemical constituents of walnuts, has many favorable effects on heart and vascular system function. The cardiovascular effect of walnuts depends on the metabolic status of the organism. Among the cardiovascular effects of walnuts is that they improve the FA profile in the circulation and heart in favor of n-3 polyunsaturated FAs. In addition, a favorable effect on triglyceride and cholesterol status, which reduces cardiovascular disease risk, is observed. Intake of walnuts promotes FA catabolism and has anti-inflammatory, antioxidant, and antiarrhythmic effects. Walnuts also have a beneficial effect on vascular tone, accompanied by a decrease in blood pressure and reduced risk for atherosclerosis. In conclusion, studies on experimental animals encourage the consumption of walnuts as a simple, convenient approach to improve cardiovascular health.

Context: Increasing global kimchi consumption has prompted interest in its health impact. However, comprehensive reviews of the influence of kimchi on cardiometabolic risk factors, especially meta-analyses, remain limited.

Objective: This review assessed the impact of fermented kimchi consumption on cardiometabolic risk factors by systematically reviewing human intervention and prospective cohort studies, and conducting a meta-analysis of intervention studies.

Data sources: A literature search of PubMed, EMBASE, Scopus, Web of Science, RISS, KISS, and ScienceON databases was conducted through April 30, 2024. The inclusion criteria encompassed studies that examined the effects of fermented kimchi, without any added ingredients or lactic acid bacteria, on health outcomes, including anthropometric measures, blood pressure, cardiometabolic and glycemic indicators, inflammatory cytokines, and the incidence of related chronic diseases.

Data extraction: Data extraction and quality evaluation were conducted independently by 3 researchers.

Data analysis: Pooled effect sizes were calculated as weighted mean differences (WMDs) with 95% CIs employing random-effects models.

Results: Five intervention studies (205 participants) and 4 prospective cohort studies (42 455 participants) were selected. A meta-analysis of the intervention studies revealed a significant reduction in fasting blood glucose (WMD: -1.93 mg/dL; 95% CI: -3.82, -0.03; I2 = 17.4%) following the consumption of fermented kimchi. After excluding studies that contributed to increased heterogeneity, significant inverse associations were observed between fermented kimchi consumption and triglycerides (WMD: -28.9 mg/dL; 95% CI: -53.2, -4.5; I2 = 0.0%), systolic blood pressure (WMD: -3.48 mmHg; 95% CI: -5.95, -1.01, I2 = 0.0%), and diastolic blood pressure (WMD: -2.68 mmHg; 95% CI: -4.75, -0.62; I2 = 0.0%). Prospective cohort studies linked higher kimchi intake with a lower incidence of cancer and metabolic syndrome and an increased likelihood of achieving normal body weight.

Conclusion: This review supports beneficial effects of fermented kimchi on cardiometabolic health. However, due to the limited number of studies, these findings should be interpreted cautiously, highlighting the need for further research in diverse populations.

Systematic review registration: PROSPERO registration No. CRD42024532020.

Context: Stakeholders implement nutrition education to prevent and control anemia during pregnancy. Nutrition education during pregnancy can increase the consumption of iron-folic acid (IFA) supplements and encourage behavioral changes. However, there is no comprehensive meta-analysis to determine the effectiveness of this intervention.

Objective: This review aimed to determine the effect of nutrition education on IFA supplementation (IFAS) compliance, hemoglobin level change, and prevalence of anemia in low- and middle-income countries.

Data sources: The systematic searches on Ovid Medline, Scopus, Embase (Elsevier), Web of Science, Health and Medical Collection (ProQuest), and Google Scholar were conducted until September 11, 2023. The updated searches were performed on November 16, 2023.

Data extraction: In total, 12 436 records were imported to Covidence. Of these, 9109 records were screened by title and abstract. A total of 112 records were evaluated in full, and 53 articles were ultimately included based on eligibility.

Results: Fifty-three peer-reviewed research articles met the inclusion criteria, involving 13 475 pregnant women. Those who received nutrition education during pregnancy were 2.80 times more likely to comply with IFAS (odds ratio = 2.80; 95% CI: 2.04, 3.83; I2 = 66.20%). There was an average increase of 0.88 g/dL (Cohen's d = 0.88; 95% CI: 0.63, 1.13; I2 = 96.17%) in hemoglobin levels among women who received nutrition education. A meta-regression analysis revealed that 61.85% (adjusted R2 = 61.85%) of heterogeneity between standardized mean differences was explained by anemia status, intervention duration, and geographic region. Also, pregnant women in the nutrition education group had a 34% (relative risk = 0.66; 95% CI: 0.54, 0.80, I2 = 86.85%) lower risk of anemia compared with the control group.

Conclusion: Nutrition education during pregnancy improves compliance with IFAS, increases hemoglobin levels, and reduces the risk of anemia. Therefore, it is crucial to enhance the existing nutrition education program to prevent and control anemia during pregnancy.

Systematic review registration: PROSPERO registration no. CRD42023454241.

Type 2 diabetes is an inflammatory, non-infectious disease characterized by dysfunctional pancreatic β-cells and insulin resistance. Although lifestyle, genetic, and environmental factors are associated with a high risk of type 2 diabetes, nutrition remains one of the most significant factors. Specific types and increased amounts of dietary fatty acids are associated with type 2 diabetes and its complications. Dietary recommendations for the prevention of type 2 diabetes advocate for a diet that is characterized by reduced saturated fatty acids and trans fatty acids alongside an increased consumption of monounsaturated fatty acids, polyunsaturated fatty acids, and omega-3 fatty acids. Although following the recommendations for dietary fatty acid intake is important for reducing type 2 diabetes and its related complications, the underlying mechanisms remain unclear. This review will provide an update on the mechanisms of action of fatty acids on glucose metabolism and type 2 diabetes, as well as dietary recommendations for the prevention of type 2 diabetes.

Context: Inflammation and endothelial dysfunction are important risk factors for chronic diseases, including cardiovascular diseases and related mortality.

Objective: This systematic review and meta-analysis aimed to assess the effects of 2 popular dietary patterns-a Mediterranean (MED) diet supplemented with olive oil and a low-fat diet (LFD)-on factors related to inflammation and endothelial function in adults.

Data sources and data extraction: The following online databases were searched for related studies published until August 7, 2024: PubMed/Medline, Scopus, Clarivate Analytics Web of Science, Cochrane Central Register of Controlled Trials, and Google Scholar. Two independent researchers selected the studies based on the eligibility criteria.

Data analysis: The effect sizes were expressed as Hedges' g with 95% CIs. A total of 16 eligible trials with 20 effect sizes were included in the analyses. This meta-analysis revealed that the MED diet supplemented with olive oil significantly improved all of the indicators of the study compared with the LFD, except in the case of E-selectin, in which a low and nonsignificant decrease was reported.

Conclusion: Available evidence suggests that a MED diet supplemented with olive oil compared with the LFD significantly improves inflammation and serum endothelial function in adults.

Systematic review registration: PROSPERO registration no. CRD42023485718.

This review describes the state of the art regarding the prebiotic role of chitin and the interactions of chitin and chitosan with cancer cells. Chitin is the second most abundant polysaccharide in nature and a constitutive component of crustacean shells and the exoskeleton of insects. Chitosan is the deacetylated form of chitin, which is obtained by chemical processing or the enzymatic activity of deacetylases found in microorganisms and insects. Edible insects have recently been introduced in Western countries, thus raising concerns regarding food safety and due to their chitin content and the release of chitosan during the digestive process. The roles of insect chitin and chitosan in the gastrointestinal tract, microbiome modulation, and cancer have been widely investigated. Several in vitro and in vivo studies have shown the possible microbiota modulation of chitin and its relevant communication with the immune system, thus confirming its prebiotic activity. No evidence has been provided on the cancerogenic activity of chitin; however, studies have suggested that chitin has a cytotoxic effect on cancer cell lines. Chitosan has been confirmed to exhibit apoptotic and cytotoxic activities on cancer cells in several in vitro studies on cancer cell lines and in vivo models. In conclusion, the literature does not show a direct connection between the presence of chitin or chitosan and the onset of cancer. However, cytotoxic and apoptotic activities in relation to cancerous lines have been demonstrated.

Context: Vitamin C has been used as an essential antioxidant to reduce the inflammatory response associated with pneumonia and acute respiratory distress syndrome in patients with the 2019 coronavirus disease (COVID-19), but its effect on clinical outcomes remains controversial and inconclusive.

Objective: The purpose of this study was to conduct a meta-analysis and systematic review to assess the effects of vitamin C supplementation on the severity of COVID-19 in hospitalized patients.

Data sources: Web of Science, Embase, Cochrane Library, PubMed, CNKI, CSTJ, Wan fang, and CBM databases were searched for publications between January 2020 and December 2023 that met the inclusion criteria.

Data extraction: The meta-analyses of outcomes in more than one study were performed using Review Manager software. Heterogeneity was evaluated using the I2 statistic. A randomized controlled trial, cohort studies, and retrospective studies in which vitamin C supplementation was supplemented as monotherapy or in combination, compared with placebo, no treatment, or other standard treatment without vitamin C were included.

Data analysis: After screening, 22 studies, with a total of 6831 patients, were selected for assessment. Odds ratios (ORs) with 95% CIs were calculated using fixed- and random-effects models. The meta-analysis showed significant effects of vitamin C on alleviating clinical outcomes in patients with COVID-19 (OR = 0.76, 95% CI = 0.65-0.89, P = .0007) but no shortening of the length of hospitalization (OR = 1.16, 95% CI = -0.13-2.44, P = .08) compared with the control group. Notably, vitamin C supplements significantly reduced the mortality risk (OR = 0.64, 95% CI = 0.51-0.80, P = .0001) and the incidence of severity (OR = 0.59, 95% CI = 0.43-0.80, P = .0006) in COVID-19 patients.

Conclusion: The findings suggest that vitamin C supplements may have a beneficial effect on clinical outcomes, as well as reducing severity and mortality in COVID-19 patients, but more clinical randomized controlled trials are needed to evaluate the role of vitamin C in treating COVID-19.

Systematic review registration: PROSPERO registration no. CRD42023491517.