International Journal for Vitamin and Nutrition Research最新文献

Background: A growing body of evidence indicates the regulating effects of alpha-lipoic acid on iron metabolism. However, findings from clinical trials are equivocal. This systematic review and meta-analysis aimed to evaluate the quantitative effect of alpha lipoic acid (ALA) supplementation on iron metabolism parameters including serum iron, total iron binding capacity, hemoglobin, and ferritin.

Methodology: Online databases, including PubMed, Scopus, and Web of Science were searched, up to 29 May 2022, to obtain all relevant studies.

Results: A total of 1901 publications were identified in the systematic search; of which, 10 studies with a total of 529 participants were included in this meta-analysis. Pooled analysis of the studies showed no statistically significant effects of ALA on ferritin (weighted mean difference (WMD) = -11.01 ng/mL; 95% CI: -40.07, 18.05 ng/mL; I² = 0.0%, p = 0.670), serum iron (WMD = -0.47 μ/dL; 95% CI: -24.48, 23.54 μ/dL; I² = 94.7%, p < 0.001), hemoglobin (WMD = 0.49 g/dL; 95% CI: -0.54, 1.52 g/dL; I² = 95.7%, p < 0.001), and total iron binding capacity (TIBC) (WMD = 3.95 μ/dL; 95% CI: -21.3, 29.2 μ/dL; I² = 53.1%, p = 0.094). In subgroup analysis, ALA significantly increased hemoglobin in patients with hematological disorders (WMD = 1.23 g/dL; 95% CI: 1.00, 1.45 g/dL; I² = 96.6%, p < 0.001) and in studies with durations longer than 8 weeks (WMD = 1.03 g/dL; 95% CI: 0.82, 1.25 g/dL; I² = 96.5%, p = 0.02).

Conclusion: ALA supplementation had no statistically significant effect on iron-related parameters. Subgroup analysis revealed a significant increasing effect of ALA on hemoglobin in patients with hematological disorders and in studies with durations >8 weeks.

Background: Parkinson's disease (PD) is a chronic progressive neurodegenerative disease, and the exact etiology of PD has not been fully elucidated. Changes in dietary patterns play an important role in the onset and progression of PD. However, the association between specific dietary factors and PD remains unclear.

Methods: A total of 14,309 subjects from the National Health and Nutrition Examination Survey (NHANES) (2007-2016) were included. Logistic regression was used to analyze the association between 34 nutrients and PD. The regression model was adjusted for potential confounders and effect modifiers including age, gender, race, education, hypertension, and stroke.

Results: The data showed negative associations of the intake of protein (0.99 (0.98, 1.00), p = 0.018), fiber (0.96 (0.93, 0.99), p = 0.003), vitamin E (0.91 (0.86, 0.97), p = 0.005), copper (0.55 (0.36, 0.86), p = 0.009) with PD. Alpha carotene (p = 0.042), beta-carotene (p = 0.006), phosphorus (p = 0.018), magnesium (p = 0.002), sodium (p = 0.035), potassium (p = 0.001) had a potential negative correlation with PD. The intake of carbohydrate, sugars, fat, cholesterol, vitamin A, beta-cryptoxanthin, lycopene, lutein zeaxanthin, vitamin B1, vitamin B2, niacin, vitamin B6, folate, vitamin B12, vitamin C, vitamin D, vitamin K, calcium, iron, zinc, selenium, caffeine, theobromine, alcohol was not associated with PD (p > 0.05).

Conclusions: Some specific dietary elements are associated with PD, and supplementation of dietary elements may have potentially beneficial effects. However, the observed associations between dietary factors and PD may be influenced by changes in diet resulting from the disease itself, rather than diet influencing PD risk. Further longitudinal studies are needed to establish causal relationships and directionality.

Background: Non-alcoholic fatty liver disease (NAFLD) has become the primary cause of chronic liver disease. Although malnutrition is a common late-stage clinical consequence during the course of organ dysfunction and death in critical patients, it has not received sufficient attention in the context of NAFLD. The aim of this study was to explore the prevalence and prognostic significance of malnutrition in patients with NAFLD using three simple tools for nutrition assessment.

Methods: Participants (n = 3908) in the National Health and Nutrition Examination Survey (NHANES) database were divided into NAFLD (n = 1737) and non-NAFLD (n = 2171) groups. The controlling nutritional status (CONUT) score, prognostic nutrition index (PNI), and nutrition risk index (NRI) were applied to investigate the association between malnutrition and mortality among NAFLD patients.

Results: The median age of participants was 54.0 years, with females accounting for 52.2% of the study cohort. A majority of elderly male participants had NAFLD, and up to 18% of NAFLD patients suffered from malnutrition. During the average period of follow-up (24.4 ± 7.2 months), 36 all-cause deaths occurred in the NAFLD group. Multivariate analysis revealed that malnutrition was associated with significantly higher mortality compared with normal nutrition. The adjusted hazard ratio (HR) for PNI was 4.44 (95% CI: 2.07-9.53, p < 0.001), and for NRI it was 6.98 (95% CI: 1.47-33.11, p = 0.014). The CONUT score also showed a trend for association with higher mortality.

Conclusion: Malnutrition is a common comorbidity in NAFLD patients and is closely associated with poor prognosis and higher mortality. The three nutrition assessment tools employed in this study could be used to improve the predictive ability of nutritional status for mortality among NAFLD patients.

Background: Despite rising non-alcoholic fatty liver disease (NAFLD) prevalence and its impact on liver health, there's a lack of studies on grape seed extract's (GSE) effect on oxidative stress and quality of life (QoL) in NAFLD patients. This study aims to fill this gap by the potential benefits of GSE in reducing oxidative stress and improving QoL. Methods: In this randomized clinical trial study, fifty patients with NAFLD were randomly assigned to receive either 2 tablets of GSE containing 250 mg of proanthocyanidins or placebo (25 participants in each group) for two months. QoL was evaluated using the SF-36 questionnaire, and oxidative stress variables (TAC, MDA, SOD, GPx, CAT, and IL-6) were measured at the beginning and end of the study. Results: Compared with the control group, the group supplemented with GSE experienced greater reductions in IL-6 and MDA (3.14±1.43 pg/ml vs. 2.80±0.31 pg/ml; 4.16±2.09 μM vs. 4.59±1.19 μM, p for all <0.05), as well as greater increases in TAC, SOD, and GPx levels (0.18±0.08 mM vs. -0.03±0.09 mM; 10.5±6.69 U/ml vs. 8.93±1.63 U/ml; 14.7±13.4 U/ml vs. 8.24±3.03 U/ml, p for all <0.05). Furthermore, the QoL questionnaire showed that physical limitations, general health, and total physical health were significantly improved in the GSE group compared with the placebo (17.0±42.0 vs. -12.0±37.5; 3.80±14.8 vs. -3.92±9.55; 5.08 5.26 vs. -7.01±13.7, p for all <0.05). Conclusions: GSE can be effective in improving oxidative stress and QoL in patients with NAFLD. More studies are needed to confirm the results of this study.

Background: Adequate evidence supports beneficial effects of plant-derived phytochemicals against type 2 diabetes (T2D). Among phytochemicals, dietary flavonoids is one of the superb candidates. The whole studies are carried out in Western populations, so it is needed to investigate the risk of T2D by dietary flavonoid intakes in ethnic origins and other regions to confirm these relations. This study was conducted to investigate whether the daily consumption of total flavonoid and its subclasses can affect the incidence of type 2 diabetes (T2D) in the Iranian population. Methods: Eligible adults (n=6547) were selected from among participants of the Tehran lipid and glucose study with an average follow-up of 3.0 years. Dietary intakes were assessed using a valid and reliable 168-item semi-quantitative food frequency questionnaire. Multivariate Cox proportional hazard regression models were used to estimate the development of T2D in relation to total intake of flavonoids. Results: This study was conducted on 2882 men and 3665 women, aged 41.3±14.6 and 39.0±13.4 years, respectively. After adjustment for several potential confounders (age, sex, diabetes risk score, physical activity, energy, fiber and total fat intakes), risk of T2D decreased from tertiles 1 to 3 for flavonols (HR (95% CI): 1.00, 0.86 (0.64-1.16), 0.87 (0.63-0.93), P_trend=0.01) and isoflavonoids (HR (95% CI): 1.00, 0.84 (0.62-1.13), 0.64 (0.46-0.88), P_trend=0.02), whereas non-significant results were found for total flavonoid and other subclasses of flavonoid. Conclusion: These results emphasize the potential protective role of flavonols and isoflavonoids rich food (e.g. apple, tea, soy, and dark chocolate) in the prevention of T2D.

Background: esports, or organized video game competitions, have been expanding quickly. The use of dietary supplements by esports players appears vulgarized but lacks supporting evidence. Objectives: To outline studies that tested the effects of dietary supplements on video gaming, summarize their findings, highlight knowledge gaps, and recommend future research. Eligibility criteria: Clinical trials published in English between 1990 and 2023 that assessed the effects of dietary supplements on the cognitive performance of video gamers. Sources of evidence: The Web of Science, PubMed, Scopus, and Google Scholar databases. Charting methods: PRISMA's (2020) flow diagram was used to create the data chart. Results: Sixteen studies were outlined. Thirteen were randomized, thirteen applied acute interventions, ten applied a crossover design and only three weren't placebo-controlled. Of the 10 studies that included caffeine (40-200 mg), four reported significant positive effects on cognition (attention, processing speed, working memory), two on first-person shooter video gaming performance (reaction time, hit accuracy, time to hit 60 targets), and one on Tetris game score. All 3 studies that included arginine silicate (1500 mg) reported significant improvements in one or more aspects of cognition (reaction time, attention, visual representation, and spatial planning). Two studies that tested sucrose (21 and 26.8 g) didn't report significant improvements, while one study that tested 26.1 g of glucose registered significant positive effects on processing speed and sustained attention. Conclusions: The published literature has focused on the effects of caffeine, which may exert both positive and negative effects on esports players. Additional, high-quality research is needed.

Background: To conduct a systematic review and dose-response meta-analysis of current findings from randomized controlled trials (RCTs) on the effect of soluble fiber supplementation on liver function in both healthy individuals and people with specific health conditions, PubMed, Scopus, and ISI Web of Science were systematically searched for relevant RCTs published prior to April 2022. Methods: We estimated the change in liver function parameters for each 5 g/d increment in soluble fiber in each trial and then calculated the mean difference (MD) and 95%CI. A total of 25 RCTs with 27 treatment arms (1744 subjects; 884 cases, 860 controls) were included. Results: A total of 25 RCTs with 27 treatment arms were included. The intervention duration of the included studies ranged from 3 to 52 weeks and the dose of soluble fiber supplementation varied from 0.0025 to 40 g/d. Soluble fiber supplementation could not significantly affect serum alanine transaminase (MD: -0.02 U/L, 95% CI: -1.06 to 1.01), aspartate transaminase (MD: -0.34 U/L, 95% CI: -0.84 to 0.15), alkaline phosphatase (MD: 0.29 U/L, -0.14 to 0.71), gamma-glutamyl transferase (MD: 0.12 U/L; 95% CI: -0.81 to 1.05), serum bilirubin (MD: 0.42μmol/L, 95% CI: -0.08 to 0.93) and albumin (MD: 0.64 g/dl, 95% CI: -0.42 to 1.70) levels. Conclusions: Findings from this study did not support the beneficial effects of soluble fiber supplementation on liver function biomarkers. There is a need for long-term high-quality interventions to examine the effects of different types and doses of soluble fibers on liver function as primary outcome.

Intestinal permeability is a physiological property that allows necessary molecules to enter the organism. This property is regulated by tight junction proteins located between intestinal epithelial cells. However, various factors can increase intestinal permeability (IIP), including diet. Specific components in the Western diet (WD), such as monosaccharides, fat, gluten, salt, alcohol, and additives, can affect the tight junctions between enterocytes, leading to increased permeability. This review explains how these components promote IIP and outlines their potential implications for health. In addition, we describe how a reduction in WD consumption may help improve dietary treatment of diseases associated with IIP. Research has shown that some of these components can cause changes in the gut microbiota, leading to dysbiosis, which can promote greater intestinal permeability and displacement of endotoxins into the bloodstream. These endotoxins include lipopolysaccharides derived from gram-negative bacteria, and their presence has been associated with various diseases, such as autoimmune, neurological, and metabolic diseases like diabetes and cardiovascular disease. Therefore, nutrition professionals should promote the reduction of WD consumption and consider the inclusion of healthy diet components as part of the nutritional treatment for diseases associated with increased intestinal permeability.

Background: Co-administration of vitamin C and inorganic nitrate ([Formula: see text]) may reduce oxidative stress, boost the conversion of nitrite ([Formula: see text]) into NO and elicit positive vascular effects. Aims: We aimed to test the effects of oral inorganic [Formula: see text] and vitamin C co-supplementation on vascular function, muscular strength, and on concentrations of urinary [Formula: see text], vitamin C, 8-isoprostanes and salivary [Formula: see text] in healthy young adults. Methods: Ten young healthy participants were enrolled in a randomised, double-blind (only for the [Formula: see text] intervention) crossover clinical trial. Participants consumed in random order: 1) nitrate-rich beetroot juice and vitamin C (N+VC), 2) nitrate-rich beetroot juice alone (N) or 3) nitrate-depleted beetroot juice alone (ND). Resting blood pressure (BP) was measured at the research centre and at home. Non-invasive, continuous measurements of BP and cardiac function parameters were performed using a Finometer device. Free-living physical activity and hand-grip strength were assessed. Salivary [Formula: see text] and [Formula: see text] and urinary [Formula: see text], 8-isoprostanes and vitamin C concentrations were measured. Results: There were no significant differences for any of the vascular outcomes between the three interventions groups. However, analyses of within-intervention changes showed a significant lower daily systolic BP in the [Formula: see text]+vitamin C (N+VC) group only (P=0.04). Urinary [Formula: see text] (P=0.002) and salivary [Formula: see text] (P=0.001) were significantly higher in the N+VC group compared to the N and ND groups. Conclusion: These preliminary findings suggest that combining dietary [Formula: see text] with vitamin C could have protective effects on vascular function in young adults and could represent an effective strategy for the maintenance of healthy cardiovascular trajectories.

According to previous studies, astaxanthin exerts various biological effects due to its anti-inflammatory and antioxidant capabilities; however, its effects on liver enzymes have not yet been well elucidated. Therefore, we conducted a meta-analysis to assess astaxanthin's effects on liver enzymes. A systematic literature search was conducted using scientific databases including PubMed, Scopus, Web of Science, the Cochrane databases, and Google Scholar up to February 2023 to find relevant randomized controlled trials (RCTs) examining the effects of astaxanthin supplementation on alanine transaminase (ALT), aspartate transaminase (AST), gamma-glutamyl transferase (GGT), and alkaline phosphatase (ALP). A random-effects model was used for the estimation of the pooled weighted mean difference (WMD). Overall, we included five trials involving 196 subjects. The duration of the intervention was between 4 and 48 weeks, and the dose was between 6 and 12 mg/day. ALT levels increased in the intervention group compared to the control group following astaxanthin supplementation (WMD: 1.92 U/L, 95% CI: 0.16 to 3.68, P=0.03), whereas supplementation with astaxanthin had a non-significant effect on AST (WMD: 0.72 U/L, 95% CI: -0.85 to 2.29, P=0.36), GGT (WMD: 0.48 U/L, 95% CI: -2.71 to 3.67, P=0.76), and ALP levels (WMD: 2.85 U/L, 95% CI: -7.94 to 13.63, P=0.60) compared to the placebo group. Our data showed that astaxanthin supplementation increases ALT concentrations in adults without affecting the levels of other liver enzymes. Further long-term and well-designed RCTs are necessary to assess and confirm these findings.