Ginger intervention on body weight and body composition in adults: a GRADE-assessed systematic review and dose-response meta-analysis of 27 randomized controlled trials

CONTEXT

Ginger consumption may have an inverse relationship with obesity and metabolic syndrome parameters; however, clinical trials have reported contradictory results.

OBJECTIVE

To systematically review and analyze randomized controlled trials (RCTs) assessing the effects of ginger on body weight and body composition parameters.

METHODS

Databases were searched for appropriate articles up to August 20, 2022. All selected RCTs investigated the impact of ginger on glycemic indices in adults. A random effects model was used to conduct a meta-analysis, and heterogeneity was assessed using the I2 statistic. Net changes in body weight, body mass index (BMI), waist circumference (WC), and percent body fat were used to calculate the effect size, which was reported as a weighted mean difference (WMD) and 95% confidence intervals (CIs). The risk of bias was assessed.

RESULTS

A total of 27 RCTs involving 1309 participants were included. The certainty in the evidence was very low for WC and BMI, and low for body weight and percent body fat as assessed by the GRADE evidence profiles. The meta-analysis showed a significant association between ginger supplementation and a reduction in body weight (WMD, -1.52 kg; 95%CI, -2.37, -0.66; P < 0.001), BMI (WMD, -0.58 kg/m2; 95%CI, -0.87, -0.30; P < 0.001), WC (WMD, -1.04 cm; 95%CI: -1.93, -0.15; P = 0.021), and percent body fat consumption (WMD, -0.87%; 95%CI, -1.71, -0.03; P = 0.042). The results of the nonlinear dose-response analysis showed a significant association between the ginger dose with body weight (Pnonlinearity = 0.019) and WC (Pnonlinearity = 0.042). The effective dose of ginger intervention for body mass reduction was determined to be 2 g/d in dose-response analysis. The duration of ginger intervention had a significant nonlinear relationship with body weight (Pnonlinearity = 0.028) with an effective duration of longer than 8 weeks.

CONCLUSIONS

Our findings provide evidence that ginger consumption may significantly affect body composition parameters nonlinearly. More, well-constructed RCTs are needed.

The Effect of Therapeutic Doses of Culinary Spices in Metabolic Syndrome: A Randomized Controlled Trial

Non-communicable diseases (NCDs) place a significant burden on global health and the healthcare systems which support it. Metabolic syndrome is a major risk factor for a large number of NCDs; however, treatments remain limited. Previous research has shown the protective benefits of edible dietary spices on key components of metabolic syndrome. Therefore we performed a 12-week double-blind, placebo-controlled, randomized, clinical trial to evaluate the effect of ginger (Zingiber officinale), cinnamon (Cinnamomum), and black seed (Nigella sativa) consumption on blood glucose, lipid profiles, and body composition in 120 participants with, or at risk of, metabolic syndrome. Each participant consumed 3 g/day of powder (spice or placebo). Data related to different parameters were collected from participants at the baseline, midpoint, and endpoint of the intervention. Over the 12-week interventions, there was an improvement in a number of biochemical indices of metabolic syndrome, including fasting blood glucose, HbA1c, LCL, and total cholesterol associated with supplementation with the spices when compared to a placebo. This study provides evidence to support the adjunct use of supplementation for those at risk of metabolic syndrome and its sequelae.

A Scoping Review of the Clinical Evidence for the Health Benefits of Culinary Doses of Herbs and Spices for the Prevention and Treatment of Metabolic Syndrome

Metabolic syndrome (MetS) is a growing global health problem. Evidence suggests that diets rich in phytochemical-containing herbs and spices can contribute to reducing the risk of chronic diseases. This review assesses the scope of evidence supporting the use of herbs and spices in the diet for the prevention or treatment of MetS and its associated health conditions. A search of the PubMed, Scopus and Google Scholar databases was carried out to assess the available clinical evidence for culinary doses of commonly used herbs and spices. Trials that were measuring health factors related to metabolic disorders in healthy individuals, or the health of individuals with MetS or associated diseases, were included. Out of a total of 1738 papers identified, there were 142 relevant studies on black pepper, chilli, cardamom, cinnamon, coriander, cumin, fennel, fenugreek, garlic, ginger, nigella seed, rosemary, sage and turmeric. No relevant research was found for cloves, mint, oregano, parsley or thyme. Cinnamon, fenugreek and ginger were the herbs/spices with the most published trials on them and that showed promise for glycaemic control. Cardamom appears to have potential to reduce inflammatory markers, and cinnamon, ginger and turmeric to reduce blood lipids. Patients with type 2 diabetes were the population most likely to be included in studies, but the preventative benefits of herbs/spices in healthy populations were also investigated, particularly for chilli, ginger and cinnamon. There is evidence for the beneficial effect of culinary doses of many common herbs/spices in the prevention and treatment of MetS and associated disorders.

Effect of ginger (Zingiber officinale) intake on human serum lipid profile: Systematic review and meta-analysis

Dyslipidemia is associated with an increased risk of cardiovascular events. Effect of ginger supplementation on lipid profile in humans remains controversial particularly in diabetic patients. A systematic search was performed covering PubMed, Medline, and Scopus, Web of Science (ISI), and Google scholar from January 2010 to January 2022. Inclusion criteria were randomized controlled clinical trials (RCT) study design, at least one of lipid profile components triglyceride (TG), total cholesterol (TC), low-density lipoprotein (LDL-C), and high-density lipoprotein (HDL-C) measured before and after ginger consumption. For quantitative data synthesis, a random-effects model was applied. Pooled data showed that ginger intake reduced TC (SMD -0.44; 95% CI: -0.86, -0.02; p = 0.025) and TG (SMD -0.61; 95% CI: -1.14, -0.08; p = 0.024) levels significantly, but it has no significant effect on improving HDL-C (SMD 0.40; 95% CI: -0.01, 0.80; p = 0.057) and LDL-C (SMD -0.34; 95% CI: -0.81, 0.13; p = 0.153). Ginger supplementation decreased TG in obese and diabetic subjects more efficiently. In terms of ginger dose, the result of meta-regression found to be significant only for TC, so that increasing daily doses of ginger reduces TC levels by (β: -0.67; 95% CI: -1.28, -0.07; p = 0.028). Therefore, ginger could be considered as an effective lipid lowering nutraceuticals.

Efficacy of Ginger Supplementation in Relieving Persistent Hypothyroid Symptoms in Patients with Controlled Primary Hypothyroidism: A Pilot Randomized, Double-Blind, Placebo-Controlled Clinical Trial

Primary hypothyroidism is a common disease. Some patients have persistent symptoms despite normal serum thyroid-stimulating hormone (TSH) levels. Ginger is reported to be beneficial in relieving similar symptoms. Our aim was to evaluate the efficacy of ginger supplementation in relieving persistent symptoms in these patients. In this randomized, double-blind, placebo-controlled clinical trial, 60 hypothyroid patients aged 20-60 years with normal serum TSH concentrations were randomly allocated to two equal parallel study groups of ginger (500 mg twice a day) or placebo for 30 days. Hypothyroid symptoms were evaluated as the primary outcome using the Thyroid Symptom Rating Questionnaire (ThySRQ) before and after the intervention. Anthropometric measures and laboratory indices including TSH, triglyceride (TG), total cholesterol (TChol), and fasting blood sugar (FBS) were considered as secondary outcomes. A significant lower mean total ThySRQ score (8.63 ± 5.47 vs. 15.76 ± 6.09, P < 0.001) was observed in the ginger group compared to the control group. Ginger led to significant improvements in the mean scores of the weight gain, cold intolerance, constipation, dry skin, appetite, memory loss, concentration disturbance, and feeling giddy or dizzy domains (P < 0.001). However, no significant improvements were observed in hair loss, nail fragility, hearing, hoarseness, speech, and depression or feeling down (P > 0.05). Ginger supplementation also led to a significant decrease in body weight, body mass index, waist circumference, serum TSH, FBS, TG, and TChol levels compared to the placebo. In summary according to preliminary results of this study, ginger supplementation can help relieve persistent hypothyroid symptoms. Also, it may have beneficial effects in terms of weight reduction and regulation of the FBS and lipid profile in hypothyroid patients.

The Effect of Ginger (Zingiber officinale) on Improving Blood Lipids and Body Weight; A Systematic Review and Multivariate Meta-analysis of Clinical Trials

BACKGROUND

Beneficial effects of ginger consumption on metabolic biomarkers has been reported previously. The current research aimed to investigate the effects of ginger supplementation on lipid profile and body weight using a meta-analysis of randomized, controlled trials.

METHODS

Online databases PubMed, Embase, Web of Science, and Science Direct were searched until December 2021 to identify eligible articles. Twenty-six trials were included.

RESULTS

The results showed that ginger consumption could significantly improve lipid profile including total triglyceride (-12.54 (-20.01 to -5.08)), cholesterol (-6.53 (-10.76 to -2.31)), LDL (-5.14 (-8.79 to -1.50)), and HDL (1.13 (0.35 to 1.91)). Moreover, ginger supplementation could significantly decrease body mass index (BMI) (-0.49 (-0.79 to -0.18)). However, the small number of sample studies that investigated reductions in body weight (-0.52 (-1.48 to 0.43)) were not statistically significant. Sub-group analysis of treatment dose and duration showed that in most of the analyzed lipid profiles, both ≤1500 and >1500 mg/d for both of ≤8 and >8 weeks could be effective; however, in the case of weight control dose of >1500 mg/d for more than 8 weeks was more effective. Besides, the results of multivariate meta-analysis revealed the effect of the intervention on all lipid profiles simultaneously.

CONCLUSION

The present meta-analysis and review revealed that ginger supplementation can improve lipid profile and body weight if used at the appropriate dose and duration. More studies are needed to fully evaluate the effect of ginger supplements' different doses and duration on lipid profile and BMI.

The Role of Bioactive Compounds from Dietary Spices in the Management of Metabolic Syndrome: An Overview

Metabolic syndrome (MetS) is a combination of physiologically dysregulated parameters that can include elevated fasting blood glucose, high blood pressure, central obesity, increased triglyceride levels, insulin resistance, diabetes, elevated low density lipoprotein levels, and reduced high density lipoprotein levels in the blood. Effective clinical management of MetS is critical as it is strongly associated with long lasting and fatal complications in patients. Alongside standard care of lifestyle changes and medication, dietary supplements derived from herbal resources could be an alternative therapeutic strategy that is safe, efficient, culturally acceptable, and has few side effects. Of the dietary supplements, spicy foods have always been considered a great source of functional bioactive compounds. Herbal therapy is broadly used in many countries as a treatment or as a preventive measure in the management of MetS risk factors, including blood glucose, blood pressure, and blood lipid levels. Herein, an attempt is made to evaluate the recent studies in the management of MetS with herbal alternatives, and to explore the possibility of their use as therapeutic treatments or supplements.

Effect of ginger (Zingiber officinale) supplementation on oxidative stress parameters: A systematic review and meta-analysis

A wide variety of antioxidant properties are attributed to ginger (Zingiber officinale) and several randomized controlled trials (RCTs) have investigated the effect of ginger intake on major oxidative stress (OS) parameters. We conducted a systematic review and meta-analysis to evaluate the effects of using ginger to improve OS levels. Medline, Scopus, ISI Web of Science, EMBASE, and the Cochrane Central Register of Controlled Trials were systematically searched up until March 2020 to gather RCTs that evaluated the impact of ginger intake on the levels and activity of OS parameters in adult subjects. Means and standard deviations for relevant OS variables were extracted and evaluated to assess the quality of the trials based on the Cochrane risk-of-bias tool for randomized trials. The gathered data were pooled and expressed as standardized mean difference (SMD) with 95% Confidence Intervals (95% CI). Twelve trials were included in this review. Ginger intake was shown to significantly increase glutathione peroxidase (GPx) activity (SMD: 1.64; 95% CI: 0.43, 2.85; I2  = 86.8%) and total antioxidant capacity (TAC) (SMD: 0.40; 95% CI: 0.06, 0.73; I2  = 42.8%) and significantly decrease malondialdehyde (MDA) levels (SMD: -0.69; 95% CI: -1.26, -0.12; I2  = 85.8%) compared to control groups. Ginger supplementation also non-significantly associated with an increase in CAT activity (SMD: 1.09; 95% CI: -0.07, 2.25; I2  = 87.6%). This systematic review and meta-analysis presents convincing evidence supporting the efficacy of ginger supplementation on improving OS levels. PRACTICAL IMPLICATIONS: In health sciences, OS, due to its pivotal role in the pathophysiology of several chronic diseases, is a subject with a long history. Recent research strives for a safe, ideal, and effective antioxidant. Ginger is herbal medicine, which has been widely used in traditional and complementary medicine. Proving the antioxidant effect and potential benefit of ginger has positive clinical implications for the application of this practical herb.

Phytochemicals as Potential Epidrugs in Type 2 Diabetes Mellitus

Type 2 diabetes Mellitus (T2DM) prevalence has significantly increased worldwide in recent years due to population age, obesity, and modern sedentary lifestyles. The projections estimate that 439 million people will be diabetic in 2030. T2DM is characterized by an impaired β-pancreatic cell function and insulin secretion, hyperglycemia and insulin resistance, and recently the epigenetic regulation of β-pancreatic cells differentiation has been underlined as being involved. It is currently known that several bioactive molecules, widely abundant in plants used as food or infusions, have a key role in histone modification and DNA methylation, and constituted potential epidrugs candidates against T2DM. In this sense, in this review the epigenetic mechanisms involved in T2DM and protein targets are reviewed, with special focus in studies addressing the potential use of phytochemicals as epidrugs that prevent and/or control T2DM in vivo and in vitro. As main findings, and although some controversial results have been found, bioactive molecules with epigenetic regulatory function, appear to be a potential replacement/complementary therapy of pharmacological hypoglycemic drugs, with minimal side effects. Indeed, natural epidrugs have shown to prevent or delay the T2DM development and the morbidity associated to dysfunction of blood vessels, eyes and kidneys due to sustained hyperglycemia in T2DM patients.

Effectiveness of ginger in reducing metabolic levels in people with diabetes: a randomized clinical trial

OBJECTIVE

to evaluate the effectiveness of ginge (Zingiber officinale) in reducing blood sugar and lipid levels in people with type 2 diabetes.

METHOD

a randomized and double-blind clinical trial conducted with people with type 2 diabetes in primary care facilities. The study included individuals aged between 20 and 80 years old, using oral antidiabetic drugs and with HbA1c levels between 6.0% and 10%. The participants were paired 1:1, allocated in two distinct groups, and randomized in blocks, based on their HbA1c levels. In the experimental group, the participants used 1.2g of ginger and, in the control group, 1.2g of placebo, daily for 90 days. The primary outcome was a reduction in fasting blood sugar and HbA1c, and the secondary outcome was a reduction in lipids and HOMA-IR. 103 individuals completed the study, 47 in the experimental group and 56 in the control group.

RESULTS

the participants in the experimental group showed a greater reduction in the blood glucose and total cholesterol values compared to the control group.

CONCLUSION

the use of ginger can help in the treatment of people with diabetes, and data support the inclusion of this herbal drug in the clinical practice of nurses. RBR-2rt2wy.

An evaluation of randomized controlled trials on nutraceuticals containing traditional Chinese medicines for diabetes management: a systematic review

BACKGROUND

Nutraceuticals containing traditional Chinese medicine (TCM) are promoted for use in the management of diabetes. The evidence to support such use is largely unknown. This study aimed to summarise and evaluate the literature reporting the results of randomized controlled trials (RCTs) investigating the effects of nutraceuticals in people living with diabetes.

METHODS

Literature from four electronic databases (PubMed, Scopus, CINAHL and Web of Science) was searched following PRISMA guidelines to yield RCT publications on nutraceutical for diabetes management published since 2009. The quality of reporting was assessed using the CONSORT 2010 checklist statement. Risk-of-bias for each study was assessed using the Cochrane risk of bias tool.

RESULTS

Out of 1978 records identified in the initial search, 24 randomized, double/triple-blinded, controlled trials that investigated the effect of nutraceuticals covering 17 different TCM herbs for diabetes management were selected. Participants included people who were diabetic (n = 16), pre-diabetic (n = 3) or predisposed to diabetes (n = 5). Sample sizes ranged between 23 and 117 for 2 arms, or 99-165 for 3 arms. Comparisons were made against placebo (n = 22), conventional medicine (n = 1), or regular diet (n = 1) for a duration between 4 and 24 weeks. All but one study tested the effect on fasting blood glucose levels (n = 23) or glycated haemoglobin levels (n = 18), and/or postprandial 2-h blood glucose levels (n = 4) as the primary outcomes. Nineteen studies reported some statistically significant reductions in the respective measures while 5 studies showed no effect on primary or secondary outcomes. None of the included studies met all the criteria for the CONSORT guidelines. Incomplete reporting about randomization and blinding, and a lack of ancillary analyses to explore other influential factors and potential harms associated with the use were repeatedly noted. Based on the Cochrane risk-of-bias tool, 19 studies were deemed to have a high risk of bias mainly attributed to sponsor bias.

CONCLUSIONS

There is some evidence to suggest positive clinical outcomes in response to the administration of a range of nutraceuticals containing TCM in the management of diabetes. However, these results must be interpreted with caution due to the overall low quality of the trials.

The influence of the fatty acid amide hydrolase 385C>A single nucleotide polymorphisms on obesity susceptibility

The chronic over-activation of the endogenously produced cannabinoids in obesity has been demonstrated in several studies. A common 385C>A single nucleotide polymorphism of the fatty acid amide hydrolase, one the most important inactivating enzymes of endogenous cannabinoids, has been shown to be associated with obese phenotype. This study was designed to investigate the FAAH gene polymorphisms and to compare the obesity indices between different genotypes in Iranian overweight/obese women. A total of 180 healthy overweight/obese subjects (BMI = 25 to 40 kg/m²) and 86 normal weight individuals (BMI = 18.5 to 24.9 kg/m²) were genotyped for 385 C/A polymorphism of FAAH using amplification refractory mutation system (ARMS)-PCR. Anthropometric indices including BMI, waist circumference, neck circumference, waist to height ratio, fat mass were evaluated. A written informed consent form was given by the participants. The genotype and allele frequencies were significantly different between the overweight/obese and control groups (P = 0.04). Significant differences were observed between the CC genotype and the AA+CA genotype regarding the anthropometric indices (P < 0.05). Compared to CC group, a higher BMI, WC, WHtR, NC and fat mass was identified in allele A carriers group. After adjusting for age, marital and physical activity status, it was revealed that having the CA/AA genotype increased the probability of obesity risk almost two times (P < 0.05, 95% CI 1.19-3.67). Our findings showed that the frequency of A allele was greater in overweight/obese individuals. Also, a mutation in FAAH gene was associated with higher anthropometric indices and the CA/AA genotype increased significantly the possibility of being obese in Iranian women.

The Gastro-protective Effect of Ginger (Zingiber officinale Roscoe) in Helicobacter pylori Positive Functional Dyspepsia

Purpose: The present study aimed to assess the effect of ginger (Zingiber officinale) powder supplementation on Helicobacter pylori eradication and improvement of dyspeptic symptoms in patients with H. pylori positive functional dyspepsia (FD). Methods: During this pilot study 15 patients with H. pylori positive FD received 3 g/d ginger powder as three 1-g tablets for 4-weeks. Dyspepsia symptoms were asked before and after the intervention using a questionnaire based on the Rome III criteria. H. pylori eradication was also assessed by a non-invasive stool antigen (HpSAg) test. Results: Ginger consumption accompanied by significant H. pylori eradication rate of 53.3% (P = 0.019) and the odds ratio (95% CI) was 8 (1.07 to 357.14). Moreover, our results showed significant changes in most of the dyspepsia symptoms after ginger supplementation. Conclusion: According to our findings, Z. officinale can be considered as a useful complementary therapy for FD. However, due to the small number of clinical trials in this area, further welldesigned clinical trials are needed to explicitly talk about its effectiveness especially about the eradication of H. pylori.

The effect of ginger supplementation on lipid profile: A systematic review and meta-analysis of clinical trials

BACKGROUND

Elevated levels of blood lipids are a major cause of atherosclerosis and consequently cardiovascular disease. Several studies used ginger as a lipid lowering agent.

PURPOSE

The aim of the present systematic review and meta-analysis was to clarify the effect of ginger supplementation on lipid parameters.

METHODS

PubMed, Scopus, Science Direct, ISI Web of Science and Google Scholar were systematically searched until May 2017 to find clinical trials which examined effect of ginger supplementation on level of lipid parameters in adult participants. Means for blood lipids and potential sources of heterogeneity were extracted. A subgroup analysis was applied to find out potential sources of inter-study heterogeneity.

RESULTS

A total of 12 trials (586 participants) were included in the meta-analysis. Pooled analysis suggested that ginger supplementation reduced triacylglycerol (TAG) (-17.59 mg/dl; 95% CI: -29.32 to -5.87) and low density lipoprotein cholesterol (LDL-C) (-4.90 mg/dl; 95% CI: -22.30 to -6.17). Ginger had no significant effect on total cholesterol (TC) (-5.13 mg/dl, 95% CI: -11.05 to 0.78; P = 0.089) and high density lipoprotein cholesterol (HDL-C) (2.18 mg/dl, 95% CI: -0.08 to 4.45; P = 0.059). As inter-study heterogeneity was high, studies were classified by ginger dosage. Stratified analysis showed a significant reduction in TC (-12.26 mg/dl; 95% CI: -22.37 to -2.16) and TAG (-38.42 mg/dl; 95% CI: -57.01 to -19.82) in studies which used ≤2 g/day of ginger. However, a similar significant effect was not observed in trials with >2 g/day of ginger. Neither studies which used ≤2 g/day nor trials which used >2 g/day of ginger showed significant changes in LDL-C or HDL-C.

CONCLUSION

The present systematic review and meta-analysis suggests that ginger had a favorable effect on TAG and LDL-C. Also, the result revealed that low dose of ginger (≤2 g/day) had greater lowering impact on TAG and TC. Further studies with large-scale and better design are needed to confirm this result.

The effects of ginger intake on weight loss and metabolic profiles among overweight and obese subjects: A systematic review and meta-analysis of randomized controlled trials

This systematic review and meta-analysis of randomized controlled trials (RCTs) was performed to summarize the effect of ginger intake on weight loss, glycemic control and lipid profiles among overweight and obese subjects. We searched the following databases through November 2017: MEDLINE, EMBASE, Web of Science, and Cochrane Central Register of Controlled Trials. The relevant data were extracted and assessed for quality of the studies according to the Cochrane risk of bias tool. Data were pooled using the inverse variance method and expressed as Standardized Mean Difference (SMD) with 95% Confidence Intervals (95% CI). Heterogeneity between studies was assessed by the Cochran Q statistic and I-squared tests (I2). Overall, 14 studies were included in the meta-analyses. Fourteen RCTs with 473 subjects were included in our meta-analysis. The results indicated that the supplementation with ginger significantly decreased body weight (BW) (SMD -0.66; 95% CI, -1.31, -0.01; P = 0.04), waist-to-hip ratio (WHR) (SMD -0.49; 95% CI, -0.82, -0.17; P = 0.003), hip ratio (HR) (SMD -0.42; 95% CI, -0.77, -0.08; P = 0.01), fasting glucose (SMD -0.68; 95% CI, -1.23, -0.05; P = 0.03) and insulin resistance index (HOMA-IR) (SMD -1.67; 95% CI, -2.86, -0.48; P = 0.006), and significantly increased HDL-cholesterol levels (SMD 0.40; 95% CI, 0.10, 0.70; P = 0.009). We found no detrimental effect of ginger on body mass index (BMI) (SMD -0.65; 95% CI, -1.36, 0.06; P = 0.074), insulin (SMD -0.54; 95% CI, -1.43, 0.35; P = 0.23), triglycerides (SMD -0.27; 95% CI, -0.71, 0.18; P = 0.24), total- (SMD -0.20; 95% CI, -0.58, 0.18; P = 0.30) and LDL-cholesterol (SMD -0.13; 95% CI, -0.51, 0.24; P = 0.48). Overall, the current meta-analysis demonstrated that ginger intake reduced BW, WHR, HR, fasting glucose and HOMA-IR, and increased HDL-cholesterol, but did not affect insulin, BMI, triglycerides, total- and LDL-cholesterol levels.

Effects of Ginger (Zingiber officinale Roscoe) on Type 2 Diabetes Mellitus and Components of the Metabolic Syndrome: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Objective

This article aims to assess the effects of ginger (Zingiber officinale Roscoe) on type 2 diabetes mellitus (T2DM) and/or components of the metabolic syndrome (MetS).

Methods

Electronic literature was searched in PubMed, Embase, the Cochrane Library, Chinese Biomedical Database, China National Knowledge Infrastructure, and Wanfang Database from inception of the database to May 19, 2017, and supplemented by browsing reference lists of potentially eligible articles. Randomized controlled trials on research subjects were included. Data were extracted as a mean difference (MD) and 95% confidence interval (CI). Subgroup analysis of fasting blood glucose (FBG) was performed.

Results

10 studies met the inclusion criteria with a total of 490 individuals. Ginger showed a significant beneficial effect in glucose control and insulin sensitivity. The pooled weighted MD of glycosylated hemoglobin (HbA1c) was −1.00, (95% CI: −1.56, −0.44; P < 0.001). Subgroup analysis revealed that ginger obviously reduced FBG in T2DM patients (−21.24; 95% CI: −33.21, −9.26; P < 0.001). Meanwhile, the significant effects of improvement of lipid profile were observed. Most analyses were not statistically heterogeneous.

Conclusion

Based on the negligible side effects and obvious ameliorative effects on glucose control, insulin sensitivity, and lipid profile, ginger may be a promising adjuvant therapy for T2DM and MetS.