The effect of ginseng (the genus panax) on glycemic control: a systematic review and meta-analysis of randomized controlled clinical trials.

Despite the widespread use of ginseng in the management of diabetes, supporting evidence of its anti-hyperglycemic efficacy is limited, necessitating the need for evidence-based recommendations for the potential inclusion of ginseng in diabetes management.To elucidate the effect of ginseng on glycemic control in a systematic review and meta-analysis of randomized controlled trials in people with and without diabetes.MEDLINE, EMBASE, CINAHL and the Cochrane Library (through July 3, 2013).Randomized controlled trials ≥30 days assessing the glycemic effects of ginseng in people with and without diabetes.Relevant data were extracted by 2 independent reviewers. Discrepancies were resolved by consensus. The Heyland Methodological Quality Score and the Cochrane risk of bias tool were used to assess study quality and risk of bias respectively.Sixteen trials were included, in which 16 fasting blood glucose (n = 770), 10 fasting plasma insulin (n = 349), 9 glycated hemoglobin (n = 264), and 7 homeostasis model assessment of insulin resistance (n = 305) comparisons were reported. Ginseng significantly reduced fasting blood glucose compared to control (MD =  -0.31 mmol/L [95% CI: -0.59 to -0.03], P = 0.03). Although there was no significant effect on fasting plasma insulin, glycated hemoglobin, or homeostasis model assessment of insulin resistance, a priori subgroup analyses did show significant reductions in glycated hemoglobin in parallel compared to crossover trials (MD = 0.22% [95%CI: 0.06 to 0.37], P = 0.01).Most trials were of short duration (67% trials<12wks), and included participants with a relatively good glycemic control (median HbA1c non-diabetes = 5.4% [2 trials]; median HbA1c diabetes = 7.1% [7 trials]).Ginseng modestly yet significantly improved fasting blood glucose in people with and without diabetes. In order to address the uncertainty in our effect estimates and provide better assessments of ginseng's anti-diabetic efficacy, larger and longer randomized controlled trials using standardized ginseng preparations are warranted.ClinicalTrials.gov NCT01841229

Effect of Replacing Animal Protein with Plant Protein on Glycemic Control in Diabetes: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Previous research on the effect of replacing sources of animal protein with plant protein on glycemic control has been inconsistent. We therefore conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to assess the effect of this replacement on glycemic control in individuals with diabetes. We searched MEDLINE, EMBASE, and Cochrane databases through 26 August 2015. We included RCTs ≥ 3-weeks comparing the effect of replacing animal with plant protein on HbA1c, fasting glucose (FG), and fasting insulin (FI). Two independent reviewers extracted relevant data, assessed study quality and risk of bias. Data were pooled by the generic inverse variance method and expressed as mean differences (MD) with 95% confidence intervals (CIs). Heterogeneity was assessed (Cochran Q-statistic) and quantified (I2-statistic). Thirteen RCTs (n = 280) met the eligibility criteria. Diets emphasizing a replacement of animal with plant protein at a median level of ~35% of total protein per day significantly lowered HbA1c (MD = −0.15%; 95%-CI: −0.26, −0.05%), FG (MD = −0.53 mmol/L; 95%-CI: −0.92, −0.13 mmol/L) and FI (MD = −10.09 pmol/L; 95%-CI: −17.31, −2.86 pmol/L) compared with control arms. Overall, the results indicate that replacing sources of animal with plant protein leads to modest improvements in glycemic control in individuals with diabetes. Owing to uncertainties in our analyses there is a need for larger, longer, higher quality trials. Trial Registration: ClinicalTrials.gov registration number: NCT02037321

Effect of Replacing Animal Protein with Plant Protein on Glycemic Control in Diabetes: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Previous research on the effect of replacing sources of animal protein with plant protein on glycemic control has been inconsistent. We therefore conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to assess the effect of this replacement on glycemic control in individuals with diabetes. We searched MEDLINE, EMBASE, and Cochrane databases through 26 August 2015. We included RCTs ≥ 3-weeks comparing the effect of replacing animal with plant protein on HbA1c, fasting glucose (FG), and fasting insulin (FI). Two independent reviewers extracted relevant data, assessed study quality and risk of bias. Data were pooled by the generic inverse variance method and expressed as mean differences (MD) with 95% confidence intervals (CIs). Heterogeneity was assessed (Cochran Q-statistic) and quantified (I2-statistic). Thirteen RCTs (n = 280) met the eligibility criteria. Diets emphasizing a replacement of animal with plant protein at a median level of ~35% of total protein per day significantly lowered HbA1c (MD = −0.15%; 95%-CI: −0.26, −0.05%), FG (MD = −0.53 mmol/L; 95%-CI: −0.92, −0.13 mmol/L) and FI (MD = −10.09 pmol/L; 95%-CI: −17.31, −2.86 pmol/L) compared with control arms. Overall, the results indicate that replacing sources of animal with plant protein leads to modest improvements in glycemic control in individuals with diabetes. Owing to uncertainties in our analyses there is a need for larger, longer, higher quality trials. Trial Registration: ClinicalTrials.gov registration number: NCT02037321

Forest plots of controlled clinical trials investigating the effect of ginseng on glycated hemoglobin.

<p>The diamond represents a pooled effect estimate. Paired analyses were applied to all crossover trial <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0107391#pone.0107391-Elbourne1" target="_blank">[18]</a>. Data are mean differences (MD) with 95% CI. <i>P</i> values are for Generic Inverse Variance random effects models. Inter-study heterogeneity was tested by the Cochran Q statistic at a significance level of <i>P</i> <0.10 and quantified by the I² statistic, where I² ≥ 50% is considered to be evidence of substantial heterogeneity.</p

Characteristics of Studies Investigating the Effect of Ginseng on Glycemic Outcomes.

<p>Abbreviations: T1DM – Type 1 Diabetes mellitus; T2DM – Type 2 Diabetes mellitus; Pre-DM – Pre-diabetes Mellitus; EHPT – Essential hypertension; F – Female; M – Male; BMI – Body mass index; C – Control group; T – Treatment group; T1 – Treatment group #1; T2 – Treatment group #2; T3 – Treatment group #3; IP – Inpatient; OP – Outpatient; MQS – Heyland Methodological Quality Score; N/R – Not reported.</p><p>*Studies by Sotaniemi et al. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0107391#pone.0107391-Sotaniemi1" target="_blank">[7]</a>, Yoon et al. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0107391#pone.0107391-Yoon1" target="_blank">[30]</a>, and Reeds et al. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0107391#pone.0107391-Reeds1" target="_blank">[25]</a> contained multiple comparisons, and to mitigate unit-of-analysis error, we combined groups to create a single pairwise comparison.</p>†<p>Pre-DM included subjects with either Impaired Fasting Glucose or Impared Glucose Tolerance.</p>‡<p>Pre-study baseline BMI is listed. The study by Rhee et al. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0107391#pone.0107391-Rhee1" target="_blank">[26]</a> did not report SD for the mean BMI of participants.</p>§<p>Pre-study baseline endpoints are listed. In studies were these values were not reported, the start value of control was assumed to be equivalent to baseline and was reported. Where start of control value was not given, of control value was assumed to be equivalent to baseline and was reported. Assumed values are reported in bold. The study by Reay et al. (a) & (b) <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0107391#pone.0107391-Reay1" target="_blank">[24]</a> used n = 23 and n = 14 respectively for reporting data on fasting blood glucose, n = 17 and n = 12 respectively for reporting data on fasting plasma insulin, and n = 18 and n = 11 respectively for reporting data on HbA1c.</p><p>∥Ginseng dose is reported individually for trials with multiple treatment groups.</p>¶<p>All ginseng doses were compared to placebo, a control group that did not receive ginseng, or fermented soybean.</p><p>**Study quality was assessed by the Heyland Methodological Quality Score (MQS) and trials with a score ≥ 8 were considered to be of high quality.</p>††<p>Agency funding is that from government, university or not-for-profit health agency sources. None of the trialists declared conflicts of interest.</p><p>All data is expressed as mean ± SD.</p><p>Characteristics of Studies Investigating the Effect of Ginseng on Glycemic Outcomes.</p

Forest plots of controlled clinical trials investigating the effect of ginseng on FBG.

<p>The diamond represents a pooled effect estimate. Paired analyses were applied to all crossover trials <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0107391#pone.0107391-Elbourne1" target="_blank">[18]</a>. Data are mean differences (MD) with 95% CI. <i>P</i> values are for Generic Inverse Variance random effects models. Inter-study heterogeneity was tested by the Cochran Q statistic at a significance level of <i>P</i> <0.10 and quantified by the I² statistic, where I² ≥ 50% is considered to be evidence of substantial heterogeneity.</p

Flow of the literature search for the effect of ginseng on glycemic outcomes (FBG, FPI, HbA1c, and HOMA-IR).

<p>Flow of the literature search for the effect of ginseng on glycemic outcomes (FBG, FPI, HbA1c, and HOMA-IR).</p

Forest plots of controlled clinical trials investigating the effect of ginseng on homeostasis model assessment of insulin resistance.

<p>The diamond represents a pooled effect estimate. Paired analyses were applied to all crossover trials <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0107391#pone.0107391-Elbourne1" target="_blank">[18]</a>. Data are mean differences (MD) with 95% CI. <i>P</i> values are for Generic Inverse Variance random effects models. Inter-study heterogeneity was tested by the Cochran Q statistic at a significance level of <i>P</i> <0.10 and quantified by the I² statistic, where I² ≥ 50% is considered to be evidence of substantial heterogeneity.</p

Effect of Tree Nuts on Glycemic Control in Diabetes: A Systematic Review and Meta-Analysis of Randomized Controlled Dietary Trials

<div><p>Background</p><p>Tree nut consumption has been associated with reduced diabetes risk, however, results from randomized trials on glycemic control have been inconsistent.</p><p>Objective</p><p>To provide better evidence for diabetes guidelines development, we conducted a systematic review and meta-analysis of randomized controlled trials to assess the effects of tree nuts on markers of glycemic control in individuals with diabetes.</p><p>Data Sources</p><p>MEDLINE, EMBASE, CINAHL, and Cochrane databases through 6 April 2014.</p><p>Study Selection</p><p>Randomized controlled trials ≥3 weeks conducted in individuals with diabetes that compare the effect of diets emphasizing tree nuts to isocaloric diets without tree nuts on HbA1c, fasting glucose, fasting insulin, and HOMA-IR.</p><p>Data Extraction and Synthesis</p><p>Two independent reviewer’s extracted relevant data and assessed study quality and risk of bias. Data were pooled by the generic inverse variance method and expressed as mean differences (MD) with 95% CI’s. Heterogeneity was assessed (Cochran Q-statistic) and quantified (I²).</p><p>Results</p><p>Twelve trials (n = 450) were included. Diets emphasizing tree nuts at a median dose of 56 g/d significantly lowered HbA1c (MD = −0.07% [95% CI:−0.10, −0.03%]; P = 0.0003) and fasting glucose (MD = −0.15 mmol/L [95% CI: −0.27, −0.02 mmol/L]; P = 0.03) compared with control diets. No significant treatment effects were observed for fasting insulin and HOMA-IR, however the direction of effect favoured tree nuts.</p><p>Limitations</p><p>Majority of trials were of short duration and poor quality.</p><p>Conclusions</p><p>Pooled analyses show that tree nuts improve glycemic control in individuals with type 2 diabetes, supporting their inclusion in a healthy diet. Owing to the uncertainties in our analyses there is a need for longer, higher quality trials with a focus on using nuts to displace high-glycemic index carbohydrates.</p><p>Trial Registration</p><p>ClinicalTrials.gov <a href="https://clinicaltrials.gov/ct2/show/NCT01630980?term=NCT01630980&rank=1" target="_blank">NCT01630980 </a></p></div