Nutrition reviews最新文献

Microbial transglutaminase (mTG) is a frequently consumed processed food additive, and use of its cross-linked complexes is expanding rapidly. It was designated as a processing aid and was granted the generally recognized as safe (GRAS) classification decades ago, thus avoiding thorough assessment according to current criteria of toxicity and public health safety. In contrast to the manufacturer's declarations and claims, mTG and/or its transamidated complexes are proinflammatory, immunogenic, allergenic, pathogenic, and potentially toxic, hence raising concerns for public health. Being a member of the transglutaminase family and functionally imitating the tissue transglutaminase, mTG was recently identified as a potential inducer of celiac disease. Microbial transglutaminase and its docked complexes have numerous detrimental effects. Those harmful aspects are denied by the manufacturers, who claim the enzyme is deactivated when heated or by gastric acidity, and that its covalently linked isopeptide bonds are safe. The present narrative review describes the potential side effects of mTG, highlighting its thermostability and activity over a broad pH range, thus, challenging the manufacturers' and distributers' safety claims. The national food regulatory authorities and the scientific community are urged to reevaluate mTG's GRAS status, prioritizing public health protection against the possible risks associated with this enzyme and its health-damaging consequences.

Time-restricted feeding (TRF) is a lifestyle intervention that aims to maintain a consistent daily cycle of feeding and fasting to support robust circadian rhythms. Recently, it has gained scientific, medical, and public attention due to its potential to enhance body composition, extend lifespan, and improve overall health, as well as induce autophagy and alleviate symptoms of diseases like cardiovascular diseases, type 2 diabetes, neurodegenerative diseases, cancer, and ischemic injury. However, there is still considerable debate on the primary factors that contribute to the health benefits of TRF. Despite not imposing strict limitations on calorie intake, TRF consistently led to reductions in calorie intake. Therefore, while some studies suggest that the health benefits of TRF are primarily due to caloric restriction (CR), others argue that the key advantages of TRF arise not only from CR but also from factors like the duration of fasting, the timing of the feeding period, and alignment with circadian rhythms. To elucidate the roles and mechanisms of TRF beyond CR, this review incorporates TRF studies that did not use CR, as well as TRF studies with equivalent energy intake to CR, which addresses the previous lack of comprehensive research on TRF without CR and provides a framework for future research directions.

Context: Proper nutrition represents 1 of the domains of adolescents' well-being. In this context, the Mediterranean diet (MD), as a healthy, traditional, and sustainable dietary pattern, plays a crucial role in promoting adequate growth and preventing chronic noncommunicable diseases.

Objective: The currently available evidence on the effects of adherence to the MD (AMD) in association with several physical health outcomes in adolescence is summarized in this review.

Data sources: Five electronic databases were searched.

Study selection: Systematic reviews with or without meta-analysis of observational studies and randomized clinical trials, published in English during 2013-2022, and that assessed the health impact of AMD among adolescents were eligible.

Data extraction: Details on study design, methods, population, assessment of dietary patterns, health outcomes, and main results were extracted.

Results: The search yielded 59 references after removal of duplicates. Applying PICOS criteria, 4 systematic reviews and 3 meta-analyses ultimately were included in this review. The AMD was evaluated in association with overweight/obesity and adiposity in 2 studies, musculoskeletal health in another 2, inflammation in 1 study, and cardiometabolic health in 1 study. The seventh review examined all mentioned health outcomes (overweight and obesity, musculoskeletal health, inflammation, and cardiometabolic health) in relation to AMD.

Conclusions: Overall, this umbrella review showed limited evidence and a lack of consistency about the relation between AMD and health outcomes of interest in adolescence, indicating the need for more studies to better understand it.

Systemic review registration: PROSPERO registration no. CRD42023428712.

Context: Previous research linked vitamin D deficiency in pregnancy to adverse pregnancy outcomes.

Objective: Update a 2017 systematic review and meta-analysis of randomized controlled trials (RCTs) on the effect of vitamin D supplementation during pregnancy, identify sources of heterogeneity between trials, and describe evidence gaps precluding a clinical recommendation.

Data sources: The MEDLINE, PubMed, Europe PMC, Scopus, Cochrane Database of Systematic Reviews, Web of Science, and CINAHL databases were searched. Articles were included that reported on RCTs that included pregnant women given vitamin D supplements as compared with placebo, no intervention, or active control (≤600 IU d-1). Risk ratios (RRs) and mean differences were pooled for 38 maternal, birth, and infant outcomes, using random effects models. Subgroup analyses examined effect heterogeneity. The Cochrane risk of bias tool was used.

Data extraction: Included articles reported on a total of 66 trials (n = 17 276 participants).

Data analysis: The median vitamin D supplementation dose was 2000 IU d-1 (range: 400-60 000); 37 trials used placebo. Antenatal vitamin D supplementation had no effect on the risk of preeclampsia (RR, 0.81 [95% CI, 0.43-1.53]; n = 6 trials and 1483 participants), potentially protected against gestational diabetes mellitus (RR, 0.65 [95% CI, 0.49-0.86; n = 12 trials and 1992 participants), and increased infant birth weight by 53 g (95% CI, 16-90; n = 40 trials and 9954 participants). No effect of vitamin D on the risk of preterm birth, small-for-gestational age, or low birth weight infants was found. A total of 25 trials had at least 1 domain at high risk of bias.

Conclusion: Additional studies among the general pregnant population are not needed, given the many existing trials. Instead, high-quality RCTs among populations with low vitamin D status or at greater risk of key outcomes are needed. Benefits of supplementation in pregnancy remain uncertain because current evidence has high heterogeneity, including variation in study context, baseline and achieved end-line 25-hydroxyvitamin D level, and studies with high risk of bias.

Systematic review registration: PROSPERO registration no. CRD42022350057.

Context: Existing evidence on the relation between folate intake and biomarkers with mortality risk is controversial.

Objective: Previous cohort studies were examined regarding folate intake and biomarkers in relation to risk of all-cause, cardiovascular disease- (CVD), and cancer-related mortality through a systematic review and meta-analysis.

Data sources: A systematic search was performed of the PubMed, Scopus, and ISI Web of Science databases up to July 2023.

Data extraction: Prospective cohort studies examining the association of folate biomarkers (in serum, plasma, red blood cells) and intake with risk of all-cause, CVD-, and cancer-related mortality were considered. A random-effects model was applied to combine study-specific risk estimates. Dose-response relations were assessed by 1-stage weighted mixed-effects meta-analysis.

Data analysis: A total of 25 cohorts with 423 304 participants, 36 558 all-cause, 12 662 CVD-, and 2426 cancer-related deaths were included. No significant association was observed between the highest levels of folate biomarkers and all-cause mortality risk (hazard ratio [HR], 0.91; 95% CI, 0.77-1.06; n = 17; I2 = 89.4%; P < .001), CVD-related mortality risk (HR, 0.97; 95% CI, 0.87-1.06; n = 11; I2 = 0.0%; P = .57), and cancer-related mortality risk (HR, 0.85; 95% CI, 0.69-1.05; n = 6; I2 = 57.8%; P = .04) compared with the lowest. Furthermore, each 10 nmol/L increase was marginally related to a 12% reduced all-cause mortality risk but not to CVD- and cancer-related mortality risk. A significant inverse association was found between highest intake of dietary folate and the lowest, and risk of all-cause (HR, 0.87; 95% CI, 0.78-0.96; n = 3; I2 = 63.6%; P = .06) and CVD (HR, 0.77; 95% CI, 0.57-0.93; n = 4; I2 = 80.2%; P = .002) mortality.

Conclusions: This meta-analysis revealed a significant inverse relation between dietary folate intake and risk of all-cause and CVD mortality. Such an association was not found in the case of folate biomarkers. Further prospective studies are warranted to confirm these findings.

Systematic review registration: PROSPERO registration no. CRD42023401700.

Context: Assessing the overall sustainability of a diet is a challenging undertaking requiring a holistic approach capable of addressing the multicriteria nature of this concept.

Objective: The aim was to identify and summarize the multicriteria measures used to assess the sustainability characteristics of diets reported at the individual level by healthy adults.

Data sources: Articles were identified via PubMed, Scopus, and Web of Science. The search strategy consisted of key words and MeSH terms, and was concluded in September 2022, covering references in English, Spanish, and Portuguese.

Data extraction: This systematic review followed the PRISMA guidelines. The search identified 5663 references, from which 1794 were duplicates. Two reviewers independently screened the titles and abstracts of each of the 3869 records and the full-text of the 144 references selected. Of these, 7 studies met the inclusion criteria.

Data analysis: A total of 6 multicriteria measures were identified: 3 different Sustainable Diet Indices, the Quality Environmental Costs of Diet, the Quality Financial Costs of Diet, and the Environmental Impact of Diet. All of these incorporated a health/nutrition dimension, while the environmental and economic dimensions were the second and the third most integrated, respectively. A sociocultural sustainability dimension was included in only 1 of the measures.

Conclusion: Despite some methodological concerns in the development and validation process of the identified measures, their inclusion is considered indispensable in assessing the transition towards sustainable diets in future studies.

Systematic review registration: PROSPERO registration no. CRD42022358824.

Context: Pregnancy increases nutrient demand, but how nutrient uptake and its determinants adapt to facilitate this is unclear.

Objective: This review aimed to identify and characterize evidence and evidence gaps regarding changes in gastrointestinal nutrient absorption and its determinants during pregnancy in monogastric mammals.

Data sources: A scoping review of peer-reviewed sources was conducted across PubMed, Scopus, Web of Science, Embase, and ProQuest (theses and dissertations) databases.

Data extraction: Data extracted included species, pregnancy stages and outcomes. Where sufficient data for a given outcome was available, relative values were summarized graphically or in tables, to allow comparison across pregnancy stages and/or small intestine regions. Searches identified 26 855 sources, of which only 159 were eligible. Mechanistic studies were largely restricted to rodents, and most compared non- and late-pregnant groups, with fewer studies including early- or mid-pregnant groups.

Data analysis: During pregnancy, there is some evidence for greater capacity for glucose uptake but unchanged amino acid uptake, and good evidence for increased uptake of calcium, iron, and zinc, and slower gastrointestinal passage of nutrients. The available evidence indicates that acute glucose uptake, gastric emptying, and the activities of sucrase, maltase, and lactase do not change during pregnancy. Gaps in the knowledge include the effects of pregnancy on uptake of specific amino acids, lipids, and most minerals and vitamins.

Conclusion: The results indicate that the gastrointestinal tract adapts during pregnancy to facilitate increased nutrient absorption. Additional data is required in order to assess the underlying mechanisms for and impacts on the absorption of many nutrients, as well as to determine the timing of these adaptations.

Context: The global prevalence of type 2 diabetes mellitus (DM2) has been rising significantly over the years. Recent studies have shown beneficial effects of cinnamon on metabolic biomarkers.

Objective: The objective of this review was to assess the effect of cinnamon supplementation on metabolic biomarkers in patients with DM2.

Data sources: The Pubmed/MEDLINE, Cochrane CENTRAL, and Embase databases were searched up to November 10, 2022.

Data extraction: A systematic search was performed for randomized controlled trials (RCTs) evaluating the effect of cinnamon supplementation on metabolic biomarkers, in adults and the elderly with DM2, and comparing the data for a cinnamon intervention group with that for a placebo group or a control group. The main exclusion criteria were studies (1) with other types of diabetes (ie, gestational diabetes or type 1 diabetes), (2) without cinnamon consumption, (3) that did not evaluate metabolic biomarkers, or (4) in vitro and animal studies. Two researchers independently screened 924 records, evaluated full-text studies, extracted data, and appraised their quality. A third researcher was consulted to resolve any discrepancies. The data were pooled using random-effects models and expressed as the weighted mean difference (WMD) with 95% CI. Heterogeneity was assessed using Cochran's Q test and quantified using I2 statistics. Risk of bias was assessed using the Joanna Briggs Institute (JBI) instrument. Sensitivity analysis and the GRADE system were used to assess the robustness and certainty of the findings.

Data analysis: In total, 28 RCTs with a duration ranging from 30 to 120 days and a total enrollment of 3054 patients with DM2 were included. Participants consuming cinnamon showed a significant reduction in fasting blood glucose (FBG) (WMD: -15.26 mg/dL; 95% CI: -22.23 to -8.30; I2 = 88%), postprandial glucose (WMD: -39.22 mg/dL; 95% CI: -63.90 to -14.55; I2 = 100%), HbA1c (WMD: -0.56 mg/dL; 95% CI: -0.99 to -0.13; I2 = 94%), and HOMA-IR (WMD = -0.76, 95% CI: -1.13 to -0.39; I2 = 22%) compared with the control group. An intervention of cinnamon in capsule form reduced FBG (WMD:-18.43 mg/dL, 95% CI: -26.32 to -10.53; I2 = 89%), postprandial glucose (WMD: -44.83 mg/dL, 95% CI: -70.67 to -18.99; I2 = 100%), HbA1c (WMD: -0.56 mg/dL, 95% CI: -1.02 to -0.09; I2 = 94%), total cholesterol (WMD: -13.39 mg/dL; 95% CI: -24.71 to -2.07; I2 = 96%), LDL-C (WMD: -6.49 mg/dL, 95% CI: -12.69 to -0.29; I2 = 92%), and triglycerides (WND: -19.75 mg/dL; 95% CI, -33.71 to -5.80; I2 = 88%). Both doses (≤2 g/day and >2 g/day) reduced FBG and postprandial glucose. Only cinnamon doses of ≤2 g/day reduced HbA1c (WMD: -0.68 mg/dL, 95% CI: -1.16 to -0.1; I2 = 92%), HOMA-IR (WMD: -0.94 mg/dL; 95% CI: -1.21 to -0.67; I2 = 0%), and BMI (WMD: -1.18 kg/m2; 95% CI: -1.97 to -0.39; I2 = 0%).

Conclusion: The data

Context: Vitamin E, a well-known antioxidant with numerous positive effects on human health, encompasses tocotrienol-rich fraction (TRF), a natural variant abundant in palm oil.

Objective: This systematic review analyzed findings from randomized controlled trials published until 2022 to evaluate the health impacts of palm TRF.

Data sources: A literature search was performed in Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, OVID Medline, SCOPUS, and Web of Science from inception until December 2022. Thirty studies involving 2646 patients, including both healthy individuals and those with underlying conditions, were identified.

Results: This review shows palm TRF to be a promising natural supplement against inflammation and lipid peroxidation and that can significantly enhance overall health. Additionally, the study underscores the necessity for further research to ascertain the optimal dosage, formulation, and duration of supplementation, maximizing the potential health advantages.

Conclusion: This systematic review provides evidence supporting the health benefits associated with palm TRF.

Systematic review registration: PROSPERO registration no. CRD42020204070.

Context: Oral health and food oral-processing issues emerge with functional decline in the older adult population, potentially increasing the risk of malnutrition. Impairment of oral health is associated with poorer nutrition status; however, the relationship between oral factors and the intake of each nutrient remains poorly understood.

Objective: The associations between different oral factors and nutrient intakes among community-dwelling older adults were investigated.

Data sources: A literature search from 5 databases (Web of Science, Scopus, Cochrane Library, Ovid [MEDLINE and Embase], and CINAHL) was completed on February 1, 2022. The search was limited to peer-reviewed articles published between the years 2012 and 2022.

Data extraction: Six cross-sectional studies were included in the meta-analysis. Two authors independently completed the data extraction and summarized the study characteristics, factors adjusted for in the statistical analysis, the outcome, and summary statistics of the results.

Data analysis: Meta-analyses showed evidence of a significant association between compromised oral factors (namely, denture status, chewing ability, and the number of teeth) with lower energy (weighted mean difference [WMD], -107 kcal d-1 (95% CI, -132 to -81), protein (WMD, -5.2 g d-1; 95% CI, -6.6 to -3.8), fat (WMD, -4.6 g d-1; 95% CI, -6.7 to -2.6), carbohydrate (WMD, -8.8 g d-1; 95% CI, -13.9 to -3.7), and vitamin C intakes (WMD, -12.9 mg d-1; 95% CI, -16.6 to -9.2) in older adults.

Conclusion: Oral health can be an indicator of compromised daily energy, protein, fat, carbohydrate, and vitamin C intakes in older adults. However, the small sample size of the studies included in this review and the heterogeneity among macronutrient studies should be considered. Because of the lack of studies covering all aspects of food oral processing (eg, salivary flow rate, tongue pressure), the associations between oral processing and nutrient intake were not thoroughly explored.

Systematic review registration: PROSPERO registration no. CRD42022308823.