Breastfeeding and the Longitudinal Changes of Body Mass Index in Childhood and Adulthood: A Systematic Review

Mounting evidence supports the beneficial role of breastfeeding in lowering obesity risk, but the enduring impact of breastfeeding on longitudinal changes in body mass index (BMI) (i.e., BMI trajectories) remains unclear. This systematic review summarized evidence on how breastfeeding influenced the longitudinal trajectories of BMI later in life. Literature searches were conducted in Medline, Embase, Web of Science, and ScienceDirect to identify studies that assessed how breastfeeding (versus other feeding types or duration) was associated with longitudinal trajectories of BMI or BMI z-score. Three randomized controlled trials (RCTs) and 24 longitudinal cohort studies were included. Two-thirds (18/27) of studies were rated as acceptable or high quality. Most cohort studies (9/11) showed that children who continued to breastfeed at 3 to 12 mo of age had a lower BMI trajectory or lower odds of following a high BMI trajectory than those who were formula-fed or mixed-fed. The BMI differences between breastfeeding and other feeding groups were evident from age 7 mo and remained up to 8 y, and the magnitude of between-group BMI differences increased with age. For breastfeeding duration, 12 out of 15 cohort studies found that longer breastfeeding duration was associated with lower BMI trajectories up to age 18 y. Moreover, beneficial associations were observed for both exclusive and any breastfeeding with BMI trajectory. In contrast, mixed findings were reported from 3 RCTs that compared BMI trajectories from birth to ages 12 to 24 mo between breastfeeding promotion versus control or breastfeeding versus formula-feeding groups. The current review provides further longitudinal evidence from cohort studies that breastfeeding versus formula/mixed feeding or longer breastfeeding duration was associated with lower BMI trajectories. Such associations initiated in early childhood became more apparent with age and were sustained into early adulthood. The existing evidence substantiates the importance of breastfeeding promotion and continuation to support obesity prevention.

The effect of sodium-glucose co-transporter-2 (SGLT2) inhibitors on blood interleukin-6 concentration: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

The low-grade chronic inflammation in diabetes plays an important role in development of cardiovascular and renal complications. Sodium-glucose co-transporter-2 (SGLT2) inhibitors are recognized as protective agents for cardio-renal complications. Interleukin-6 (IL-6) is positively associated with the pathophysiology of metabolic-related pathologies. The aim of this meta-analysis is to investigate the effect of SGLT2 inhibitors on blood IL-6 concentration in randomized controlled trials (RCTs).

METHODS

Embase, PubMed, and Scopus were systematically searched up to 1st of November 2023. The eligible studies were RCTs with adult population that had provided blood IL-6 for both control and intervention groups. Cochrane risk-of-bias tool were for study quality assessment. Data were analyzed using random effect model via Stata statistical software.

RESULTS

Eighteen studies with a total of 5311 patients were included. Of which 3222 and 2052 patients were in intervention and control arm, respectively. Of the total population, 49.7% were men. The study durations ranged from 8 to 52 weeks. The pooled analysis showed a significant association between the use of SGLT2 inhibitors and lower IL-6 levels (standardized mean difference (SMD) = -1.04, Confidence Interval (CI): -1.48; -0.60, I2 = 96.93%). Dapagliflozin was observed to have a higher IL-6-lowering effect (SMD = -1.30, CI: -1.89; -0.71, I2 = 92.52) than empagliflozin or canagliflozin. Sub-group analysis of control groups (SMD = -0.58 (-1.01, -0.15) and -1.35 (-2.00, -0.70 for the placebo and active control sub-groups, respectively) and duration of interventions (SMD = -0.78 (-1.28, -0.28) and -1.20 (-1.86, -0.55) for study duration of ≤ 12 and > 12 weeks, respectively) did not change the results. Meta-regression analysis showed a significant correlation between the level of HbA1c and IL-6-lowering efficacy of SGLT2 inhibitors.

CONCLUSION

IL-6 levels are significantly reduced with the use of SGLT2 inhibitors with HbA1c as the only marker influencing such reductions, and dapagliflozin had the highest potency. The anti-inflammatory effect of SGLT2 inhibitors supports their broader use to address diabetic complications related to inflammatory responses.

The effects of macro-algae supplementation on serum lipid, glycaemic control and anthropometric indices: A systematic review and meta-analysis of clinical trials

INTRODUCTION

Macro-algae products have been shown to ameliorate the metabolic disorders state. Thus, highlighting their function as supplementary therapeutic agents can be a novel strategy for clinical therapies. This systematic review and meta-analysis of clinical trials aimed to summarize the effect of macro-algae consumption on serum lipid profile, glycaemic control and anthropometric factors.

METHODS

In this systematic review and meta-analysis, a comprehensive search was performed for relevant studies published up to May 2023. The Cochran's Q test and I-square (I2 ) tests were used to evaluate heterogeneity across the included studies. The meta-analysis was conducted using random-effects model (DerSimonian and Laird), and weighted mean difference (WMD) was considered as the pooled effect size.

RESULTS

Out of 8602 papers in the initial screening, eight clinical trials with a total of 438 participants were included into this meta-analysis. The results indicated that macro-algae supplementation significantly decreased serum levels of total cholesterol (TC) (WMD = -6.7 mg/dL; 95% CI: -12.59, -0.80; item = 0.026) and low-density lipoprotein cholesterol (LDL-c) (WMD = -8.25 mg/dL; 95% CI: -15.38, -1.12; p-value = .023). There was an increase in level of high-density lipoprotein cholesterol (HDL-c) (WMD = 0.48 mg/dL; 95% CI: -2.05, 3.01; p-value = .71) which was not statistically significant. Macro-algae supplementation reduced body mass index (BMI) (WMD = -0.28 kg/m2 ; 95% CI: -0.96, 0.41; p-value = .426), weight (WMD = -0.39 kg; 95% CI: -3.6, 2.83; p-value = .81), waist circumference (WC) (WMD = -0.52 cm; 95% CI: -2.71, 1.66; p-value = .64), fasting blood sugar (FBS) (WMD = -1.95 mg/dL; 95% CI: -5.19, 1.28; p-value = .24) and HbA1c (WMD = -0.02%; 95% CI: -0.14, 0.09; p-value = .66) in intervention group.

CONCLUSIONS

This meta-analysis indicated that macro-algae supplementation significantly decreased TC and LDL-c level. It can also increase HDL-c level and reduce anthropometric indices and glycaemic control factors.

The effect of dietary approaches to stop hypertension and ketogenic diets intervention on serum uric acid concentration: a systematic review and meta-analysis of randomized controlled trials

Hyperuricemia as a risk factor for metabolic diseases is proved to be profoundly modified by dietary approaches. This systematic review and meta-analysis of randomized control trials (RCT) was conducted to investigate the effect of two nutritional interventions; dietary approaches to stop hypertension (DASH) diet and ketogenic diet (KD) on serum uric acid (UA) concentrations. Our systematic search was for RCTs in which KD or DASH diet were assigned to adults for at least 2 weeks or more. Until March 2023 in Embase, Web of Science, PubMed, and Scopus databases, 10 eligible RCTs that intervened with DASH diet (n = 4) or KD (n = 6) and had provided laboratory data on serum UA were found. Summary effect was calculated by random-effects model. Results from the meta-analysis of the 4 DASH diet RCTs with a total of 590 participants revealed significant decrease in serum UA after at least 4 weeks of interventions (mean difference (MD) = ‒0.25; 95% CI ‒0.4 to ‒0.1 mg/dL; p < 0.01; I² = 0%). The pooled meta-analysis of the 6 included RCTs of KD reporting data of 267 participants showed no significant changes in serum UA (MD = 0.26; 95% CI ‒0.47 to 0.98 mg/dL, I² = 95.32%). However, a non-significant reduction of UA in the subgroup analysis of very low-calorie KD (VLCKD) studies (MD = ‒0.04; 95% CI ‒0.29 to 0.22, I² = 0%) was obtained. DASH diet has an ameliorating effect on serum UA and may be recommended for hyperuricemia states such as gout. In addition, we have shown that serum UA level following KD remained unchanged. Although, in view of the heterogeneity across the studies, further investigations are needed to determine the effect of KD and VLKD on serum UA concentrations.

Effect of zinc supplementation in the management of type 2 diabetes: A grading of recommendations assessment, development, and evaluation-assessed, dose-response meta-analysis of randomized controlled trials

The question of whether zinc supplementation may improve cardio-metabolic health in patients with type 2 diabetes mellitus (T2DM) remains controversial and require further evaluation. This study aimed to summarize the effectiveness of oral zinc supplementation in improving cardio-metabolic risk markers in people with T2DM. We searched PubMed, Scopus, and Web of Science from inception to April 2023, for randomized controlled trials (RCTs). RCTs of type 2 diabetic adults (aged ≥18 years) comparing zinc supplementation with placebo were included. We excluded studies if not randomized, involved co-supplementation, and were conducted in children or pregnant women. Glycemic indices, lipid profiles, blood pressure, anthropometric measure, c-reactive protein (CRP), creatinine, and serum zinc were extracted. Certainty of evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methods. We used a random-effect model to perform the dose-response analysis. Effect sizes were presented as mean difference (MD) and 95% confidence interval (CI). 22 studies (n = 1442 participants) were included. The certainty of the evidence was rated as moderate to high. Zinc supplementation significantly reduced glycemic indices: including two-hour postprandial glucose (2hpp) (mean difference (MD): -34.34 mg/dl; 95%CI: -51.61∼ -17.07), fast blood sugar (FBS) (MD: -23.32 mg/dl; 95% CI: -33.81∼ -12.83), and hemoglobin A1c (HbA1c) (MD: -0.47; 95% CI: -0.71∼ -0.23). Zinc had a favorable effect on lipid profiles low-density lipoprotein (LDL) (MD: -10.76 mg/dl; CI: -17.79∼-3.73), triglyceride (TG) (MD: -18.23 mg/dl; CI: -32.81∼-3.65), total cholesterol (TC) (MD: -12.74 mg/dl; CI: -21.68∼-3.80), VLDL (MD: -5.39 mg/dl; CI: -7.35∼-3.43) and high-density lipoprotein (HDL) (MD: 4.04 mg/dl; CI: 0.96 ∼ 7.12). Systolic blood pressure (SBP) (MD): -3.64 mmHg; 95% CI: -6.77∼ -0.52), weight (MD: 1.00 kg; 95% CI: 0.34∼1.66), CRP (MD: -3.37 mg/l, 95% CI: -4.05∼ -2.70), and serum zinc (MD: 15.38 µg/dl; 95% CI: 10.74∼ 20.02) changed to a statistically significant extent with zinc supplementation. There was also a linear association between additional 10 mg/d zinc treatment with FBS, HbA1c, HDL, LDL, TG, TC, and serum zinc. A non-linear dose-response gradient was seen for FBS, HDL, and SBP (p < 0.05). Egger's test showed no substantial publication bias. Our findings strongly suggest a potential beneficial effect of zinc supplementation on type 2 diabetic patients. Further high-quality research is needed to determine the optimal form, dosage, and duration of zinc supplementation for this population.

Effects of whole grain intake on glucagon-like peptide 1 and glucose-dependent insulinotropic peptide: a systematic review and meta-analysis

CONTEXT

Whole grain intake may control help glycemia and reduce food intake by affecting the secretion of glucagon-like peptide 1 (GLP-1) and glucose-dependent insulinotropic peptide (GIP).

OBJECTIVE

This systematic review and meta-analysis aimed to assess the postprandial and long-term effects of whole grains on GLP-1 and GIP levels.

DATA SOURCES

PubMed, Web of Science, and Scopus online databases were searched systematically to identify relevant randomized clinical trials (RCTs) published up to April 2021.

STUDY SELECTION

RCTs that evaluated the effects of whole grains, compared with refined grains, on the postprandial area under the curve (AUC) value, the postprandial serum concentration of incretins from 0 to 180 minutes, or the fasting level of incretins after at least 14 days of intervention were included.

RESULTS

Nineteen studies were included in the meta-analysis. The results showed that acute intake of whole grains could not significantly change the AUC value of GLP-1 or GIP. However, the AUC value of GIP was reduced more significantly in (1) unhealthy participants (standard mean difference [SMD] -1.08; 95%CI, -2.07 to -0.10; I2 = 75.9%) compared with healthy participants, and (2) those with a baseline fasting blood glucose of ≥99 mg/dL (SMD -0.71; 95%CI, -1.30 to -0.11; I2 = 74.4%) compared with those with a baseline value of < 99 mg/dL. On the other hand, the results of time-response evaluation during 0 to 180 minutes after the intake of test meals showed that serum concentrations of GIP decreased significantly from 0 to 30 minutes (coefficient = -44.72; P = 0.005), but increased from 60 to 180 minutes (coefficient = 27.03; P = 0.005). However, long-term studies found no significant effects of whole grains on fasting concentrations of GLP-1 or GIP.

CONCLUSION

Whole grain intake did not affect postprandial levels of GLP-1 but enhanced postprandial levels of GIP from 60 to 180 minutes. Further high-quality trials are required to assess the long-term effects of whole grain intake on serum levels of incretins.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42021256695.

Postmortem Histopathologic Findings and SARS-CoV-2 Detection in Autopsy Kidneys of Patients With COVID-19: A Systematic Review and Meta-Analysis

OBJECTIVES

This systematic review and meta-analysis aimed to investigate the prevalence of postmortem kidney histopathologic features of patients with coronavirus disease 2019 (COVID-19) in addition to the rate of renal tropism in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

METHODS

We searched Web of Science, PubMed, Embase, and Scopus up to September 2022 to identify eligible studies. A random-effects model was used to estimate the pooled prevalence. Cochran Q test and Higgins I2 were used to assess evidence of heterogeneity.

RESULTS

In total, 39 studies were included in the systematic review. The meta-analysis included 35 studies consisting of a total of 954 patients, with an average age of 67.1 years. The pooled prevalence of acute tubular injury (ATI)-related changes was the predominant finding (85% [95% confidence interval, 71%-95%]), followed by arteriosclerosis (80%), vascular congestion (66%), and glomerulosclerosis (40%). Endotheliitis (7%), fibrin microthrombi (12%), focal segmental glomerulosclerosis (1%), and calcium crystal deposits (1%) were seen in a smaller number of autopsies. The overall average rate of virus detection was 47.79% in the pooled data of 21 studies (272 samples).

CONCLUSIONS

The main finding-ATI-correlated to clinical COVID-19-associated acute kidney injury. The presence of SARS-CoV-2 in kidney samples in addition to vascular lesions in kidneys can be linked to direct kidney invasion by the virus.

Effect of serum lipid profile on the risk of breast cancer: systematic review and meta-analysis of 1,717,054 women

Background

Dyslipidemia has been linked to breast cancer incidence. However, conflicting results exist regarding the associations between lipid components and breast cancer development.

Purpose

The aim of the present meta-analysis was to further investigate the relationships between serum lipid profile and the risk of breast cancer.

Methods

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline was followed to conduct the present systematic review and meta-analysis. Databases such as the PubMed, EMBASE, and Web of Sciences, were searched up to the end of January 2021, using certain MeSH and non-MeSH keywords and their combination to extract related published articles.

Results

Twenty-six prospective studies met the inclusion criteria involving 1,717,054 women, of whom 36,590 were diagnosed with breast cancer during the follow-up. A negative and significant association was found between HDL-C levels and the risk of breast cancer [relative risk (RR): 0.85, 95% CI: 0.72–0.99, I2: 67.6%, p=0.04) (Figure). In contrast, TG (RR: 1.02, 95% CI: 0.91–1.13, I2: 54.2%, p=0.79), total cholesterol (TC) (RR: 0.98, 95% CI: 0.90–1.06, I2: 67.2%, p=0.57), apolipoprotein A (ApoA) (RR: 0.96, 95% CI: 0.70–1.30, I2: 83.5%, p=0.78) and LDL-C (RR: 0.93, 95% CI: 0.79–1.09, I2: 0%, p=0.386) were not associated with breast cancer development. In studies adjusting for hormone use and physical activity, TC was positively correlated to breast cancer risk (RR: 1.05, 95% CI: 1.01–1.10 and 1.05, 95% CI: 1.01–1.10, respectively), as was TG in studies adjusting for baseline lipids (RR: 0.92, 95% CI: 0.85–0.99) and race (RR: 1.80, 95% CI: 1.22–2.65).

Conclusions

In the present meta-analysis, HDL-C was inversely related to breast cancer risk. In contrast, no significant associations were found for TC (except after adjusting for hormone use and physical activity), TG (except after adjusting for baseline lipids and race), LDL-C and ApoA. Overall, data on the links between lipids and breast cancer are conflicting. However, there is increasing evidence supporting that low HDL-C is related to an increased risk for this malignancy. Further research is needed to establish the associations between different lipid components and breast cancer risk in certain populations.

Funding Acknowledgement

Type of funding sources: None.

No adverse effects of dairy products on lipid profile: A systematic review and meta-analysis of randomized controlled clinical trials

BACKGROUND AND AIMS

The current study aimed to review the effects of dairy foods on lipid profile in randomized controlled clinical trials (RCTs).

METHODS

We searched PubMed, Scopus, Embase, and Central. RCTs that assess the effects of dairy foods on lipid profile were included.

RESULTS

The overall effects of dairy foods on lipid profile were non-significant. Dairy foods were associated with a non-significant reduction in triacylglycerol level, and a non-significant increase in total cholesterol, low density lipoprotein cholesterol, and high-density lipoprotein cholesterol level.

CONCLUSION

We conclude that dairy foods doesn't have any unfavorable effects on lipids.

The effect of calcium supplement intake on lipid profile: a systematic review and meta-analysis of randomized controlled clinical trials

Despite the potential role of dietary calcium in fat excretion, the favorable effects of calcium supplements on lipid profile remains inconclusive. The current study aimed to review the effect of calcium supplement intake on lipid profile in randomized controlled clinical trials (RCTs). This systematic review and meta-analysis was conducted in PubMed, Scopus, Embase, and Central. RCTs which assessed the effects of calcium supplementation on lipid profile were included. All outcomes were recorded as continuous variables, and the effect size was measured. We classified studies according to dose of supplement, study duration, and dyslipidemia. Calcium supplement intake was associated with a significant reduction in low density lipoprotein cholesterol (LDL-C) level (WMD:-0.08; 95%CI:-0.16,-0.01)(mmol/l), especially with intakes of at least 1000 mg/day (WMD:-0.13; 95%CI:-0.23,-0.03)(mmol/l), with intakes of at least 12 weeks (WMD:-0.08; 95%CI: -0.16,-0.00)(mmol/l), and in individuals without dyslipidemia (WMD:-0.15; 95%CI:-0.26,-0.04)(mmol/l). Also, in another subgroup analysis, consumption of less than 1000 mg/day calcium supplement caused a significant increase in Total Cholesterol (TC) level (WMD: 0.24; 95%CI: 0.05,0.42) (mmol/l). In other blood lipids or study subgroups we observed no significant effect. We concluded that calcium supplements had a favorable effect on LDL-C level, especially in individuals without dyslipidemia, higher calcium intakes, and longer period of consumption.

Association of Vitamin D Status and Metabolic Syndrome Components in Iranian Children

Background:

Recently, it has been found that Vitamin D can affect cardiometabolic risk factors. However, these findings have not been confirmed in younger population. We aimed to assess the associations of serum 25-hydroxyvitamin D (25(OH)D) and metabolic syndrome (MetS) components in Iranian children.

Methods:

This cross-sectional study was conducted on 240 children aged 6–9 years old. Anthropometric indices (weight, height, waist circumference, and body fat), biochemical parameters (low-density lipoprotein, high-density lipoprotein, triglyceride [TG], fasting blood sugar, and serum 25(OH)D), systolic blood pressure (SBP) and diastolic blood pressure (DBP) blood pressure, and dietary intake and physical activity were measured. Multivariate linear regression analysis was used to assess the association of MetS components and serum 25(OH)D.

Results:

Mean age of children was 7.8 ± 1.06 year. Mean serum 25(OH)D concentration was 14.6 ± 10.64 ng/ml, and the prevalence of Vitamin D deficiency (serum 25(OH)D lower than 10 ng/ml) was 41.66%. Dietary intake of Vitamin D was 1.91 ± 1.8 mcg/day. Serum 25(OH)D was inversely associated with TG (β = −0.16; CI: −0.27, −0.04) after adjusting by age, gender, body mass index, physical activity, and some dietary components. Serum 25(OH)D was negatively associated with SBP (β = −0.02; CI: (−0.05, −0.004), and DBP (β = −0.02; CI: −0.05, −0.003); however, it was not significant anymore after adjustment for sodium, potassium, and fiber.

Conclusions:

Vitamin D deficiency is alarming among Iranian children. Among the components of MetS, lower serum Vitamin D concentration was only associated with TG that could contribute in onset and progression of cardiometabolic disorders later in life.

Effect of nuts on energy intake, hunger, and fullness, a systematic review and meta-analysis of randomized clinical trials

Despite high energy content, nut consumption has not been associated with weight gain in epidemiological and clinical investigations. Since a satiety effect a decreased sense of hunger in the following meals has been proposed as the mechanism of nuts against obesity, the present meta-analysis was performed to examine how nut consumption affects "energy intake", "hunger", and "fullness". "Weight" was not included among the search terms but weight data were extracted from the collected articles in order to help interpreting the results. A total of 1048 trials were found, of which 31 passed the eligibility process. Daily energy intake was mostly assessed by 3-day food records, and hunger and fullness were estimated by visual analog scale (VAS). Nut consumption was associated with increased energy intake (mean difference (MD) (nuts - control) = 76.3 kcal; 95% CI: 22.7, 130 kcal; P = 0.005). In contrast, hunger suppressed following nut consumption (MD = -6.54 mm VAS; 95% CI: -12.7, -0.42 mm VAS; P = 0.03). Nuts did not affect sense of fullness and weight in the overall estimate. Subgroup analysis based on participants' BMI revealed that energy intake of overweight/obese individuals was increased following nut consumption while such effect was not observed in normal weight participants. In conclusion, pooled estimates of available clinical trials showed increased energy intake following nut consumption in overweight/obese individuals but not in persons with normal weight. Nut consumption was associated with decreased hunger but no effect was observed on fullness and weight.

Effects of Canola Oil Consumption on Lipid Profile: A Systematic Review and Meta-Analysis of Randomized Controlled Clinical Trials

Hyperlipidemia is a well- known risk factor of cardiovascular disease. A healthy diet containing vegetable oils such as canola oil (CO) may help to reduce serum lipids. This study aimed to quantify the effects of CO on lipid parameters using a systematic review and meta-analysis of randomized controlled trials. PubMed, Web of Science, Scopus, ProQuest, and Embase were systematically searched until December 2017, with no time and design restrictions. Also, a manual search was performed to find extra relevant articles. Lipid parameters including total cholesterol (TC), low-density lipoprotein cholesterol (LDL), high-density lipoprotein cholesterol (HDL), triglycerides (TG), apolipoprotein A1 (Apo A1), and apolipoprotein B (Apo B) were entered the meta-analysis. Weighed mean difference (WMD) and 95% confidence interval (CI) were stated as the effect size. Sensitivity analyses and prespecified subgroup were conducted to evaluate potential heterogeneity. Twenty-seven trials, comprising 1359 participants, met the eligibility criteria. Results of this study showed that CO consumption significantly reduced TC (-7.24 mg/dl, 95% CI, -12.1 to -2.7), and LDL (-6.4 mg/dl, 95% CI, -10.8 to -2), although it had no effects on HDL, TG, Apo B, and Apo A1. Effects of CO on TC and LDL significantly decreased after CO consumption in subgroups of >50 years of age participants and >30 intervention duration subgroup. Moreover, CO decreased LDL and TC compared to sunflower oil and saturated fat. This meta-analysis suggested that CO consumption improves serum TC and LDL, which could postpone heart disease progression. Key Teaching Points CO consumption could decrease serum TC and LDL, although it had no effects on other blood lipids. There was an overall significant effect of canola oil on TC and LDL compared to sunflower oil and saturated fats. CO could have beneficial effects on serum TC and LDL just when consumed longer than 30 days. CO consumption improved lipid profiles in participants older than 50 years.

Flavanols are potential anti-obesity agents, a systematic review and meta-analysis of controlled clinical trials

BACKGROUND

The anti-obesity potential of flavonoids has been shown by animal and human studies. In this meta-analysis, we systematically reviewed controlled clinical trials and quantified the effects of flavonoids and flavonoid subclasses on obesity-related anthropometric measures.

METHODS AND RESULTS

PubMed, EMBASE, Scopus, Web of Science, and ProQuest databases were searched to identify trials examining the effect of flavonoids on body mass index (BMI), waist circumference, and body fat percentage. Fifty eight trials passed the eligibility process. Analysis endpoints were calculated as the mean difference between baseline and post-treatment. Flavonoids were in subclasses of flavanols, flavonols, isoflavones, flavanones, anthocyanins, and proanthocyanidins. They were mostly in the form of supplements and dosages varying from 40 to 1300 mg/day. Among flavonoid subclasses, flavanols showed potential for decreasing BMI, in the overall population (mean difference (MD) = -0.28 kg/m², P = 0.04; n = 21) and in the subgroups of Asians (MD = -0.42 kg/m²; P = 0.046; n = 13), ages < 50 years (MD = -0.50 kg/m²; P = 0.008; n = 14), BMI ≥ 25 kg/m² (MD = -0.30 kg/m²; P = 0.049; n = 15), and at doses ≥ 500 mg/day (MD = -0.36 kg/m²; P = 0.049; n = 12). Isoflavones also decreased BMI of non-Asian populations (MD = -0.26 kg/m²; P = 0.035; n = 13) and doses ≥ 75 mg/day (MD = -0.34 kg/m²; P = 0.027; n = 8). In the overall assessment, flavanols also decreased waist circumference (MD = -0.60 cm; P = 0.02; n = 18) but had no significant effect on body fat percentage. The available trials did not reveal significant effects from flavonols, flavanones, and anthocyanins on the specified anthropometric measures.

CONCLUSIONS

Overall results of this meta-analysis showed that flavanols have potential against obesity.

Eating breakfast and snacks while television viewing are associated with some cardio metabolic risk factors among Iranian children

AIM

We aimed to investigate the association of eating meals while television viewing (TVV) and screen-based behaviors with cardio metabolic risk factors (CRFs) among school-aged children in Shiraz.

MATERIALS AND METHODS

This cross-sectional study was done on 409 primary school children (217 boys), aged 6-9 years. Physical activity, time spent on screen-based behaviors and frequency of eating meals while TVV were measured using a questionnaire. Anthropometric indices, fasting blood sugar (FBS), blood lipids, blood pressure (BP), dietary intakes and physical activity were assessed. Association of eating while TVV with CRFs were assessed using linear regression, adjusted for potential confounders. All statistical analysis were conducted using the Stata 13 software.

RESULTS

Fully adjusted model showed that TVV time had significant positive association with waist circumferences (WC), and BP (p <0.05). Also, we found an inverse relationship between using Computer and Video games with TG level (β=-0.3; CI: -0.64, -0.09). Children who ate two or more breakfast meal while TVV had higher WC (β=2.02; CI: 0.51, 3.53) and FBS (β=3.58; CI: 0.39, 6.78) compared to who never ate breakfast while TVV. After adjustment for Screen time and BMI, eating snacks while TVV was positively associated with FBS and systolic BP. However, Eating dinner and lunch while TVV were not significantly associated with any of CRFs after adjustment for confounders.

CONCLUSIONS

We found that both eating breakfast and snacks while TVV were associated with WC, FBS and BP in children. Also, excessive TVV was associated with WC and BP.

Comparison of blood lipid-lowering effects of olive oil and other plant oils: A systematic review and meta-analysis of 27 randomized placebo-controlled clinical trials

Objective: We aim to report a systematic review and meta-analysis of randomized controlled trials (RCTs) on effects of olive oil consumption compared with other plant oils on blood lipids. Methods: PubMed, web of science, Scopus, ProQuest, and Embase were systematically searched until September 2017, with no age, language and design restrictions. Weighed mean difference (WMD) and 95% confidence interval (CI) were expressed as effect size. Sensitivity analyses and pre specified subgroup was conducted to evaluate potential heterogeneity. Meta-regression analyses were performed to investigate association between blood lipid-lowering effects of olive oil and duration of treatment. Results: Twenty-seven trials, comprising 1089 participants met the eligibility criteria. Results of this study showed that compared to other plant oils, high-density lipoprotein level increased significantly more for OO (1.37 mg/dl: 95% CI: 0.4, 2.36). Also OO consumption reduced total cholesterol (TC) (6.27 mg/dl, 95% CI: 2.8, 10.6), Low-density lipoprotein (LDL-c) (4.2 mg/dl, 95% CI: 1.4, 7.01), and triglyceride (TG) (4.31 mg/dl, 95% CI: 0.5, 8.12) significantly less than other plant oils. There were no significant effects on Apo lipoprotein A1 and Apo lipoprotein B. Conclusion: This meta-analysis suggested that OO consumption decreased serum TC, LDL-c, and TG less but increased HDL-c more than other plant oils.

Association of eating while television viewing and overweight/obesity among children and adolescents: a systematic review and meta-analysis of observational studies

The objective of this systematic review and meta-analysis was to examine the association between eating while television viewing (TVV) and overweight or obesity in children (<18 years). A systematic search of PubMed, Scopus, Web of science, PreQuest and Embase was conducted up to April 2017; pooled odds ratio (OR) and 95% confidence intervals (CI) were calculated using a random effects model. Of 4,357 articles identified, 20 observational studies met inclusion criteria (n = 84,825) and 8 of these 20 (n = 41,617) reported OR. Eating while TVV was positively associated with obesity-related anthropometric measurements in 15 studies (75%). The meta-analysis revealed that eating while TVV was positively associated with being overweight (OR = 1.28; 95% CI: 1.17, 1.39). Subgroup analyses showed similar positive associations in both girls and boys, as well as in children who ate dinner while TVV. There was no evidence of publication bias. The present systematic review and meta-analysis suggests that eating while TVV could be a risk factor for being overweight or obese in childhood and adolescents.

Macroscopic assembly of flexible and strong green graphene fibres

The scalable production presented here facilitates flexible, strong and electrically conductive graphene fibres, which have emerged as promising graphene based electronic textiles and sensors.

Octyl glucoside induced formation of the molten globule-like state of glutamate dehydrogenase

The interaction between n-octyl-beta-D-glucopyranoside (octyl glucoside) and bovine liver glutamate dehydrogenase (GDH) was studied using techniques including equilibrium dialysis, UV-spectrophotometry, circular dichroism (CD), fluorescence energy transfer and extrinsic spectrofluorometry in 50 mM sodium phosphate buffer solution (pH 7.6). The equilibrium dialysis experiment showed a higher binding of octyl glucoside to GDH that induces up to 80% enzyme inhibition in 20 mM octyl glucoside solution. The CD study indicated that GDH retains its secondary structure in the presence of octyl glucoside, but loses a degree of its tertiary structure by acquiring a more extended tertiary structure. Measurement of the binding of a hydrophobic fluorescent probe, 1-anilino-naphthalene-8-sulfonate (ANS), to GDH revealed that the binding of ANS to GDH is increased in the presence of octyl glucoside, a finding that may be interpreted in terms of the increment of surface hydrophobic patch(es) of GDH because of its binding to octyl glucoside. Fluorescence energy transfer studies also showed more binding of the reduced coenzyme (NADH) to GDH and the Lineweaver-Burk plots (with respect to NADH) indicate the existence of substrate inhibition in the presence of octyl glucoside. These observations are aimed at explaining the formation of the molten globule-like structure of GDH, which is induced by a non-ionic detergent such as octyl glucoside.

Nickel-induced substrate inhibition of bovine liver glutamate dehydrogenase

The effects of nickel ions on reductive amination and oxidative deamination activities of bovine liver glutamate dehydrogenase (GDH) were examined kinetically by UV spectroscopy, at 27 degrees C, using 50 mM Tris, pH 7.8, containing 0.1 M NaCl. Kinetic analysis of the data obtained by varying NADH concentration indicated strong inhibition, presumably due to binding of the coenzyme to the regulatory site. In contrast, almost no inhibition was observed in the forward reaction. The fact that nickel ions have the capacity to enhance binding of NADH to the enzyme was confirmed by an electrochemical method using a modified glassy carbon electrode. Use of NADPH instead of NADH showed only a weak substrate inhibition, presumably related to lower affinity of NADPH for binding to the regulatory site. Lineweaver-Burk plots with respect to alpha-ketoglutarate and ammonium ions indicated substrate and competitive inhibition patterns in the presence of nickel ions, respectively. ADP at 0.2 mM concentration protected inhibition caused by nickel. These observations are explained in terms of formation of a nickel-NADH complex with a higher affinity for binding to the regulatory site in GDH, as compared with the situation where nickel is not present. Such effects may be important for regulation of GDH and other NADH-utilizing enzymes.