Dietary protein may play an important role in the prevention of metabolic dysfunctions. However, the way in which the protein source affects these dysfunctions has not been clearly established. The aim of the current systematic review was to compare the impact of plant- and animal-sourced dietary proteins on several features of metabolic syndrome in humans. The PubMed database was searched for both chronic and acute interventional studies, as well as observational studies, in healthy humans or those with metabolic dysfunctions, in which the impact of animal and plant protein intake was compared while using the following variables: cholesterolemia and triglyceridemia, blood pressure, glucose homeostasis, and body composition. Based on data extraction, we observed that soy protein consumption (with isoflavones), but not soy protein alone (without isoflavones) or other plant proteins (pea and lupine proteins, wheat gluten), leads to a 3% greater decrease in both total and LDL cholesterol compared with animal-sourced protein ingestion, especially in individuals with high fasting cholesterol concentrations. This observation was made when animal proteins were provided as a whole diet rather than given supplementally. Some observational studies reported an inverse association between plant protein intake and systolic and diastolic blood pressure, but this was not confirmed by intervention studies. Moreover, plant protein (wheat gluten, soy protein) intake as part of a mixed meal resulted in a lower postprandial insulin response than did whey. This systematic review provides some evidence that the intake of soy protein associated with isoflavones may prevent the onset of risk factors associated with cardiovascular disease, i.e., hypercholesterolemia and hypertension, in humans. However, we were not able to draw any further conclusions from the present work on the positive effects of plant proteins relating to glucose homeostasis and body composition.
Background: Accurate monitoring of sodium intake is necessary for evaluating strategies used to reduce sodium intake. However, no repeat survey has been conducted in representative populations in Japan to examine trends in sodium intake with the use of 24-h urinary sodium excretion, a standard evaluation method for sodium intake monitoring.Objective: The objective of this study was to examine potential trends in sodium intake by examining previous reports of 24-h urinary sodium excretion in healthy Japanese adult populations.Methods: We systematically searched for reports of 24-h urinary sodium excretion in healthy Japanese adult populations (mean age range: 18-69 y). We searched PubMed and Web of Science for English-language articles and hand-searched 7 Japanese scientific journals for Japanese-language articles. Trends in urinary sodium excretion were examined with the use of weighted linear regression and random-effects meta-regression analyses, with adjustment or stratification to address study characteristics (population mean age, percentage of men, and sample size) and study assessment for completeness of urine collection.Results: We identified 68 reports of urinary sodium excretion from 53 articles published from 1953 through 2014 that showed high rates of urinary sodium excretion in healthy Japanese adult populations (weighted mean: 4900 mg/d). The rate of urinary sodium excretion significantly decreased between 1953 and 2014, by 4350 mg/d (P < 0.001); however, the rate of reduction in urinary sodium excretion was variable and decreased with time (P-linear trend <0.001 and P-quadratic trend <0.001). In the random-effects meta-regression analysis of studies that assessed completeness of urine collection with creatinine excretion, no significant relation between urinary sodium excretion and year was observed from 1978 to 2014 (β = -16, P = 0.40).Conclusion: Despite a decrease in urinary sodium excretion in healthy Japanese adult populations between 1953 and 2014, sodium intake still exceeds the WHO recommendation for adults. This review was registered at PROSPERO as CRD42016035452.
Background: Effective treatments for the core symptoms of autism spectrum disorder (ASD) are still lacking.Objective: We aimed to update the data on the effectiveness of ω-3 (n-3) fatty acid (FA) supplementation as a treatment for ASD.Methods: The Cochrane Library, MEDLINE, and EMBASE databases were systematically searched up until August 2016 with no language restrictions for randomized controlled trials (RCTs) comparing ω-3 FA supplementation with placebo or with no supplementation. Participants were children diagnosed with ASD. All functional outcome measures reported were considered. For dichotomous outcomes, the results for individual studies and pooled statistics were reported as RRs. Mean differences (MDs) were calculated for continuous outcomes.Results: Five RCTs (183 participants) were included. With 4 exceptions, there were no statistically significant differences in ASD symptoms between groups measured by validated scales. Among studies that used the Aberrant Behavior Checklist, parents' ratings indicated significant improvement in lethargy symptoms in the ω-3 FA group compared with the placebo group (2 RCTs) (pooled MD: 1.98; 95% CI: 0.32, 3.63). Among studies that used the Behavioral Assessment System for Children, parents' ratings indicated significant worsening of both externalizing behavior (2 RCTs) (pooled MD: -6.22; 95% CI: -10.9, -1.59) and social skills (1 RCT) (MD: -7; 95% CI: -13.62, -0.38) in the ω-3 FA group compared with the placebo group. One RCT reported a significant improvement in the ω-3 FA group for the daily-living component of the Vineland Adaptive Behavior Scale (MD: 6.2; 95% CI: 0.37, 12.03). Adverse effects were similar in both groups.Conclusions: Because of the limited number of included studies and small sample sizes, no firm conclusions can be drawn. However, the limited data currently available suggest that ω-3 FA supplementation does not enhance the performance of children with ASD.

