Fenugreek (Blood Sugar)

Saffron and fenugreek have been shown to have an effect on lowering blood glucose; therefore, this study aims to evaluate the effects of using saffron and fenugreek on blood glucose control. PubMed, Cochrane Library, Scopus, and Web of Science databases were searched for relevant articles. Articles on the use of saffron or fenugreek to control blood glucose were selected in compliance with PRISMA guidelines. R software was used for statistical analysis. The mean difference (MD) and the standardized MD (SMD) were adopted, and subgroup analyses were performed according to patient's clinical condition. Nineteen studies comprised this meta-analysis. Overall, using fenugreek decreased fasting blood glucose (FBG) (SMD: -0.90; 95%CI: -1.43 to -0.38; I2 = 87%; p < 0.001), postprandial blood glucose (PPBG) (SMD: -1.13; 95%CI: -1.99 to -0.28; I2 = 94%; p < 0.001), and glycated hemoglobin (HbA1c) (SMD: -0.43; 95%CI: -0.75 to -0.12; I2 = 20%; p = 0.29). Saffron supplementation reduced FBG (MD: -9.06 mg/dl; 95%CI: -16.25 to -1.86; I2 = 40%; p = 0.12) and HbA1c (MD: -0.19%; 95%CI: -0.23 to -0.14; I2 = 0%; p > 0.99). Our results show that using saffron and fenugreek can reduce FBG, PPBG, and HbA1c; however, there are some shortcomings that require attention for these results. Further high-quality studies should be conducted to establish the clinical efficacy of herbal medicines. © 2023 John Wiley & Sons Ltd.

Metabolic syndrome (MetS) is a cluster of metabolic disorders with a heavy disease burden. Fenugreek was reported to be effective in some components of MetS. Therefore, a comprehensive review and meta-analysis of randomized controlled trials was conducted to study the effects of fenugreek on MetS indices. From the beginning until August 2022, PubMed, Embase, Scopus, and Web of science were searched. Data were analyzed using the random-effect model, and presented as weighted mean difference (WMD) and associated 95 % confidence interval (CI). This meta-analysis comprised from a total of 29 eligible RCTs with 31 arms measuring fasting plasma glucose (FPG), Triglyceride (TG), high-density lipoprotein (HDL), waist circumference (WC), systolic blood pressure (SBP), and diastolic blood pressure (DBP). The results indicated significant improving effects of fenugreek on FPG (WMD: -16.75 mg/dL; 95 % CI: -23.36, -10.15; P < 0.001), TG (-20.12 mg/dL; 95 % CI: -34.238, -5.994; P < 0.001), HDL (WMD: 3.55 mg/dL; 95 % CI: 1.98, 5.12; P < 0.001), WC (WMD: -2.51; 95 % CI: -3.78, -1.24; P < 0.001) and SBP (WMD: -3.45 mmHg; 95 % CI: -6.38, -0.52; P = 0.021); However the effect on DBP (WMD: 3.17; 95 % CI: -5.40, 11.73; P = 0.469) and BMI (WMD: -0.40 kg/m2; 95 % CI: -1.114, 0.324; P = 0.281) was not significant. Administration of fenugreek can meaningfully reduce FPG, TG, WC, and SBP and increase HDL. The overall results support possible protective and therapeutic effects of fenugreek on MetS parameters.

ETHNOPHARMACOLOGICAL RELEVANCE: A variety of herbs has been used in traditional medicine for the treatment of diabetes. However, evidence is limited regarding the efficacy of individual herbs for glycemic control. We performed a systematic review and meta-analysis to evaluate the effect of herbal supplement on glycemic control in type 2 diabetes. MATERIALS AND METHODS: Randomized controlled trials were identified through electronic searches (MEDLINE, EMBASE and Cochrane Central Register of Controlled Trials) up until February 2011, historical searches of relevant articles and personal contact with experts in the area. Studies were included in the meta-analysis if they were (1) randomized placebo-controlled trial of single herb aimed at assessing glycemic control in type 2 diabetes, (2) of at least 8 weeks duration, and (3) reporting HbA(1c). Treatment effect was estimated with mean difference in the final value of HbA(1c) and FBG between the treatment and the placebo groups. RESULTS: Nine randomized, placebo-controlled trials (n = 487 patients) were identified. Ipomoea batatas, Silybum marianum and Trigonella foenum-graecum significantly improved glycemic control, whereas Cinnamomum cassia did not. The pooled mean differences in HbA(1c) were -0.30% (95% CI -0.04% to -0.57%; P = 0.02), -1.92% (95% CI -0.51% to -3.32%; P = 0.008), and -1.13% (95% CI -0.11% to -2.14%; P = 0.03), respectively, for Ipomoea batatas, Silybum marianum, and Trigonella foenum-graecum. The corresponding values for FBG were -10.20mg/dL (95% CI -5.32 mg/dL to -15.08 mg/dL; P<0.0001) and -38.05 mg/dL (95% CI -9.54 mg/dL to -66.57 mg/dL; P = 0.009), respectively, for Ipomoea batatas and Silybum marianum. CONCLUSIONS: The current evidence suggests that supplementation with Ipomoea batatas, Silybum marianum, and Trigonella foenum-graecum may improve glycemic control in type 2 diabetes. Such effect was not observed with Cinnamomum cassia. Given the limitations of the available studies and high heterogeneity of the study results for milk thistle and fenugreek, further high quality, large controlled trials using standardized preparation are warranted to better elucidate the effects of these herbs o

BACKGROUND AND OBJECTIVES: Evidence suggests that bioactive components present in plant foods have beneficial effects. Fenugreek is commonly used in Indian culinary practices and can help to keep blood sugar levels under control. The objective of this study was to assess the efficacy of defatted fenugreek seed flakes (FenuflakesTM) on the 24-hour glycaemic response (Incremental Area Under the Curve, iAUC), variability (Mean Amplitude Glycaemic Excursion assessed by Continuous Glucose Monitoring system) in participants with type 2 diabetes. METHODS AND STUDY DESIGN: Twenty-one type 2 diabetes participants, aged 42 to 50 years, were provided with 5-day cyclic iso-caloric diets for 14 days without (control diet) and with 30 g of FenuflakesTM (test diet) in a randomized crossover trial. The Abbott Pro sensor recorded interstitial glucose concentration every 15 minutes consecutively for 14 days in the participants. Additionally, fasting plasma glucose and glycated hemoglobin (HbA1c) were assessed at the baseline and end of the study. RESULTS: 15 out of 21 participants completed the randomized control and test diet feeding periods as per protocol. There was a significant reduction in 24-hour iAUC (p=0.02) and mean amplitude glycemic excursions (p=0.006) in the test diet as compared to control diet. Furthermore, within the test diet, there was a significant reduction in fasting plasma glucose and HbA1c (p<0.05) at the end of the 14-day intervention period. CONCLUSIONS: The results suggest that the inclusion of FenuflakesTM, into regular dietary practices may effectively reduce glucose levels and enhance glycemic control in Asian Indian adults with type 2 diabetes.

OBJECTIVE: To provide pharmacists with practical information to guide consumers in their choices of herbal products and dietary supplements for the management of type 2 diabetes mellitus (T2DM) and its comorbid disease states. SUMMARY: The herbal and dietary supplement market has grown exponentially over the past decade as Americans increasingly use such agents for generalized health and the prevention and treatment of chronic disease states.1 Pharmacist advice is often requested on the use of these agents for the management of T2DM; however, this is an area that has insufficient evidence to support confident recommendations. Many published studies involving herbal agents and dietary supplements are small and poorly designed, with heterogeneous results. Pharmacists should be aware of the safety and efficacy data available for these agents, recognize potential drug interactions, and identify acceptable manufactured products. CONCLUSION: The strongest scientific evidence for blood glucose lowering effect is associated with alpha-lipoic acid and fenugreek. There is also good evidence supporting the use of ivy gourd, gymnema, and vitamin E for management of hyperglycemia; however, caution should be used when recommending vitamin E. Pharmacists should advise consumers to disclose use of any of these products to all of their health care providers.

In the current study, the potential of a novel combination of a galactomannan with acarbose (100 mg) was evaluated for attaining a desired hypoglycaemic effect over a prolonged period of time. Three major antidiabetic galactomannans viz., fenugreek gum, Boswellia gum, and locust bean gum were selected in order to achieve a synergistic effect in the treatment along with retardation in drug release. In vitro studies indicated that batches containing various proportions of fenugreek gum (AF40-60) were able to control drug release for a longer duration of approximately 10-12 h. In contrast, the matrices prepared using Boswellia and locust bean gum were able to sustain the release for relatively shorter durations. Drug release mainly followed first-order release kinetics owing to the highly soluble nature of the drug. In vivo study depicted a significant reduction (p < 0.001) in the postprandial blood glucose and triglyceride levels in the diabetic rats on treatment with formulation AF40. Thus, the developed system provides a better control of the postprandial glycaemic levels and it also obviates the need of conventional multiple dosing of acarbose. Furthermore, it also reduces the occurrence of side effects like diarrhea and loss of appetite.

Trigonella foenum graecum seed powder (TSP) and Sodium Orthovanadate (SOV) have been shown to demonstrate antidiabetic effects by stabilizing glucose homeostasis and carbohydrate metabolism in experimental type-1 diabetes. However their efficacy in controlling histopathological and biochemical abnormalities in ocular tissues associated with diabetic retinopathy is not known. The purpose of this study was to investigate the comparative efficacy of individual as well as combination therapy of TSP and SOV in 8 weeks diabetic rat lens and retina. Retinas and lenses were taken from control, alloxan-induced diabetic rats and diabetic rats treated separately with insulin, 5%TSP, SOV (0.6 mg/ml) and a combined dose of SOV (0.2 mg/ml) and 5%TSP for 60 days. Control and each experimental group had six rats. Alterations in the activities of enzymes HK (hexokinase), AR (aldose reductase), SDH (sorbitol dehydrogenase), G-6-PD (glucose-6-phosphate dehydrogenase), GPx (glutathione peroxidase), GR (glutathione reductase) and levels of metabolites like sorbitol, fructose, glucose, MDA (malondialdehyde) and GSH (reduced glutathione) were measured in the cytosolic fraction of lenses besides measuring blood glucose levels and glycosylated haemoglobin. Histopathological abnormalities were studied in the lens using photomicrography and retina using transmission electron microscopy. Blood glucose, glycosylated haemoglobin levels and polyol pathway enzymes AR and SDH increased significantly causing accumulation of sorbitol and fructose in the diabetic lens and treatment with SOV and TSP significantly (p < 0.05) decreased these to control levels. Similarly, SOV and TSP treatments modulated the activities of HK, G-6-PD, GPx and GR in the rat lens to control values. Ultrastructure of the diabetic retina revealed disintegration of the inner nuclear layer cells with reduction in rough endoplasmic reticulum and swelling of mitochondria in the bipolar cells; and these histopathological events were effectively restored to control state by SOV and TSP treatments. In this study SOV and TSP effectively controlled ocular histopathological and biochemical abnormalities associated with experimental

Oral administration of vanadate to diabetic animals have been shown to stabilize the glucose homeostasis and restore altered metabolic pathways. However, vanadate exerts these effects at relatively high doses with several toxic effects. Low doses of vanadate are relatively safe but unable to elicit any antidiabetic effects. The present study explored the prospect of using low doses of vanadate with Trigonella foenum graecum, seed powder (TSP), another antidiabetic agent, and to evaluate their antidiabetic effect in diabetic rats. Alloxan diabetic rats were treated with insulin, vanadate, TSP and low doses of vanadate with TSP for three weeks. The effect of these antidiabetic compounds was examined on general physiological parameters, Na(+)/K(+) ATPase activity, membrane lipid peroxidation and membrane fluidity in liver, kidney and heart tissues. Expression of glucose transporter (GLUT4) protein was also examined by immunoblotting method in experimental rat heart after three weeks of diabetes induction. Diabetic rats showed high blood glucose levels. Activity of Na(+)/K(+) ATPase decreased in diabetic liver and heart. However, kidney showed a significant increase in Na(+)/K(+) ATPase activity. Diabetic rats exhibited an increased level of lipid peroxidation and decreased membrane fluidity. GLUT4 distribution was also significantly lowered in heart of alloxan diabetic rats. Treatment of diabetic rats with insulin, TSP, vanadate and a combined therapy of lower dose of vanadate with TSP revived normoglycemia and restored the altered level of Na(+)/K(+) ATPase, lipid peroxidation and membrane fluidity and also induced the redistribution of GLUT4 transporter. TSP treatment alone is partially effective in restoring the above diabetes-induced alterations. Combined therapy of vanadate and TSP was the most effective in normalization of altered membrane linked functions and GLUT4 distribution without any harmful side effect.

The combined effects of Trigonella foenum-graecum and Allium sativum extracts were evaluated for their ameliorative potential in the L-thyroxine-induced hyperthyroidic rat model to contribute to an understanding of interaction between the two extracts. The investigation was carried out using two different doses. A comparison was made with the response of individual plant extracts at the previously studied effective dose in adult Wistar rats rendered hyperthyroidic by daily injections of L-thyroxine (300 microg/kg body wt., s.c.). Propylthiouracil (PTU), an antithyroid drug, was used as a reference compound. Alterations in serum triiodothyronine (T3), thyroxine (T4), glucose, hepatic glucose-6-phosphatase (G-6-Pase) and oxygen consumption were studied as end parameters. Superoxide dismutase (SOD), catalase (CAT) activities, lipid peroxidation (LPO) and reduced glutathione (GSH) were examined to reveal any toxic effects of the drugs. The combined effects of Trigonella and Allium at 200 and 500 mg/kg body wt. respectively, were equipotent as compared to the individual extracts in lowering the serum concentrations of T3 and T4 in hyperthyroidic rats. Our findings reveal that some plant extracts in combination may not always prove to be synergistic. It is therefore suggested that Trigonella foenum-graecum and Allium sativum extracts may be used individually and not together in the regulation of hyperthyroidism.

In a placebo-controlled study the effect of ginger and fenugreek was examined on blood lipids, blood sugar, platelet aggregation, fibrinogen and fibrinolytic activity. The subjects included in this study were healthy individuals, patients with coronary artery disease (CAD), and patients with non-insulin-dependent diabetes mellitus (NIDDM) who either had CAD or were without CAD. In patients with CAD powdered ginger administered in a dose of 4 g daily for 3 months did not affect ADP- and epinephrine-induced platelet aggregation. Also, no change in the fibrinolytic activity and fibrinogen level was observed. However, a single dose of 10 g powdered ginger administered to CAD patients produced a significant reduction in platelet aggregation induced by the two agonists. Ginger did not affect the blood lipids and blood sugar. Fenugreek given in a dose of 2.5 g twice daily for 3 months to healthy individuals did not affect the blood lipids and blood sugar (fasting and post prandial). However, administered in the same daily dose for the same duration to CAD patients also with NIDDM, fenugreek decreased significantly the blood lipids (total cholesterol and triglycerides) without affecting the HDL-c. When administered in the same daily dose to NIDDM (non-CAD) patients (mild cases), fenugreek reduced significantly the blood sugar (fasting and post prandial). In severe NIDDM cases, blood sugar (both fasting and post prandial) was only slightly reduced. The changes were not significant. Fenugreek administration did not affect platelet aggregation, fibrinolytic activity and fibrinogen.

Fenugreek is a widely used herbal medicine as a complementary therapy for diabetes mellitus. Lots of clinical trials have proved its beneficial effect on glycemic control parameters and lipid profiles. Thus, we conducted a systematic review and meta-analysis to evaluate the effectiveness and safety of fenugreek as a treatment for type 2 diabetes mellitus. We searched PubMed, Embase, Cochrane, China Knowledge Resource Integrated Database (CNKI), Korean studies Information Service System (KISS), Research Information Sharing Service (RISS), and ScienceON to select RCTs which used fenugreek targeting hyperglycemia with a control group. We used either a random effect model or a fixed model in a meta-analysis of Fasting blood glucose (FBG), 2 h plasma glucose during a 75 g oral glucose tolerance test (OGTT) (2-hPG), homeostatic model assessment for insulin resistance (HOMA-IR), glycosylated hemoglobin (HbA1c)/total cholesterol (TC), triglyceride (TG), high density lipoprotein (HDL-C), low density lipoprotein (LDL-C), body mass index (BMI). After screening, a total of 10 studies (706 participants) remained. Fenugreek significantly reduced FBG, 2-hPG, and HbA1c, but it did not significantly decrease HOMA-IR. Moreover, it significantly improved TC, TG, and HDL-C, while there were no significant differences in LDL-C and BMI. Hepatic or renal toxicity was not observed, and there were no severe adverse events associated with fenugreek despite mild gastrointestinal side effects in some studies. In conclusion, fenugreek improves overall glycemic control parameters and lipid profile safely.

BACKGROUND AND AIMS: There are several herbal formulations for type 2 diabetes (T2D), but many of them have never been directly compared to establish the most effective methods. Therefore, the present systematic review and network meta-analysis aimed to compare and rank the effects of herbal formulations by combining direct and indirect evidence on the management of type 2 diabetes. METHODS: From five electronic databases, relevant studies on the effectiveness of herbal formulations for glycemic status for people with type 2 diabetes were retrieved. Only randomized controlled trials that were published in English and looked at how herbal formulations affected adults' (>18-year-old) glycemic levels were included. A systematic review and network meta-analysis design with the random-effects model was used. RESULTS: A total of 44 trials included 3130 participants on six herbs were included in the final analysis. Apple cider vinegar (ACV) (standardized mean difference (SMD) = -28.99), cinnamon (-9.73), curcumin (-13.15), and fenugreek (-19.64) significantly reduced fasting blood glucose (FBG) compared with placebo (all p < 0.05). Notably, only ACV (SMD = -2.10) and fenugreek seeds (0.84) were found significantly effective in reducing HbA1C. ACV was most effective herb to reduce FBG comparison with other herbs. CONCLUSIONS: Several herbs could be considered as a valuable adjuvant therapy regarding glycemic control of type 2 diabetes patients. Health professionals should be encouraged to incorporate these herbs for the management of type 2 diabetes as part of their standard care.

Cardiometabolic risk triggers a state of chronic and subclinical inflammation, conferring a higher risk of morbidity and mortality. Thus, minimal processing of foods with high nutritional value, in the form of flour, becomes an effective dietary strategy in preventing and treating cardiometabolic risk factors. This systematic review aims to evaluate the evidence on the effect of flour-based food intake on reducing the most common cardiometabolic risk factors. We included all randomized controlled trials published up to April 2023 in the main databases PubMed, Scopus and Web of Science. Eleven clinical trials were included. The amount of flour used in the studies ranged from 1.5 g to 36 g/day, and the supplementation period ranged from six weeks to 120 days. Green jackfruit flour, green banana flour, soy flour, flour from rind of the yellow passion fruit, and fenugreek powder demonstrated significant results in improve parameters of glucose homeostasis. Chia flour, green banana flour, soy flour, and fenugreek powder showed improvements in blood pressure measurements. Brazil nut flour and chia flour reduced total cholesterol. Chia flour also increased HDL cholesterol levels. The evidence presented in the current systematic review indicates that flour-derived foods intake is related to improve cardiometabolic risk factors parameters.

Fenugreek is used for medicinal purposes in various traditions. Some studies have demonstrated that the seeds of this plant may have an anti-diabetic effect by lowering fasting blood sugar levels and improving glucose tolerance. We conducted a systematic review of the hypoglycemic effects of fenugreek. An electronic literature search was carried out in the PubMed, Google Scholar, Scopus, and Cochrane Library databases through 18 November 2022 to find trials that assessed fasting blood glucose, postprandial blood glucose, and HbA1c changes in participants treated with fenugreek and in the control group. The mean difference with 95% confidence intervals (CI) was calculated to represent the analysis. Fourteen trials, consisting of 894 participants, were included in the meta-analysis. The results showed a reduction in fasting blood glucose levels (MD: 3.70, 95% CI of -27.02, 19.62; p = 0.76), postprandial blood glucose (MD: -10.61, 95% CI of -68.48, 47.26; p = 0.72), and HbA1c (MD: -0.88, 95% CI -1.49, -0.27; p = 0.00) with fenugreek consumption. While this review and included trials that found beneficial effects of fenugreek consumption on glycemic control, the quality and heterogeneity of studies remain a concern. Given the wider availability and lower cost of fenugreek, rigorous double-blinded randomized controlled trials should be conducted with fenugreek to understand its true potential as a diabetes control herbal agent.

Cardiovascular disease (CVD) is the leading causes of mortality across the world. Some earlier studies have revealed the beneficial effects of fenugreek on the risk factors for CVDs. However, a systematic review and meta-analysis is needed to clarify its effectiveness. Accordingly, the purpose of this study was to assess the impacts of fenugreek on several cardiometabolic risk factors in adult populations. Four electronic databases including PubMed/Medline, Scopus, Embase and Cochrane Library were searched from 2000 to 31 July 2019 to identify studies with English language. Controlled clinical trials on fenugreek reported at least one of cardiometabolic risk factors was included. Pooled effect sizes were reported as Weighted Mean Differences (WMDs) and 95% confidence intervals (CIs). Trials were pooled using a random effect model with DerSimonian and Laird method. Finally, out of 2738 publications, 12 articles were included in the meta-analysis. We found that fenugreek seed vs. placebo can reduce FBS (WMD: -12.94 mg/dL, 95%CI: -21.39 mg/dL, -4.49; I2: 85.0%, p heterogeneity = 0.0001), HbA1c (WMD: -0.58%%, 95% CI: -0.99, -0.17%; I2:0%, p heterogeneity =0.61), total cholesterol (WMD:-9.13 mg/dL, 95% CI: -13.83, -4.43; I2:0, p heterogeneity = 0.48), and low-density lipoprotein cholesterol (WMD:-11.11 mg/dL, 95% CI: -20.32, -1.90; I2:1.41%, p heterogeneity = 0.36). However, no significant changes were observed in other cardiometabolic parameters. Fenugreek seed as an adjuvant therapy may reduce serum levels of FBS, LDL-C and HbA1c. However, due to high heterogeneity in glycemic status, findings must be interpreted with great caution. More placebo-controlled clinical trials are warranted to further assess the effectiveness of fenugreek as a complementary therapy to control cardio-metabolic risk factors.

BACKGROUND: The objective of this systematic review was to assess available scientific data on the efficacy and safety of medicinal food plants for the treatment of impaired glucose tolerance. METHODS: We included randomized controlled trials (RCTs) with a minimum follow-up period of 6weeks. The diagnosis was determined by fasting plasma glucose values after two-hour oral glucose tolerance testing (OGTT). Two authors independently extracted data and evaluated bias. The Cochrane tool of risk of Bias Tool was used. RESULTS: This review included ten trials. Most studies were highly biased as data were incomplete or reporting was selective. The two-hour fasting plasma glucose after the curcumin extract intervention showed statistical significance after 3, 6 and 9months: p<0.01. Also, glycosylated haemoglobin levels A1c (HbA1c) values after curcumin extract intervention showed statistical significance after 3, 6 and 9months: p<0.01. Insulin resistance (HOMA-IR) after curcumin extract intervention showed statistical significance after 6months and after 9months: p<0.05 and p<0.01. CONCLUSIONS: Curcumin has shown the confident results to be effective for the treatment of impaired glucose tolerance. Fenugreek and flaxseed may also be effective, but due to low quality of these studies the results must be interpreted with caution.

95. Br J Clin Pharmacol. 2017 Jan;83(1):211-212. doi: 10.1111/bcp.13091. Epub 2016 Sep 20. What G6PD-deficient individuals should really avoid. Lee SW(1), Chaiyakunapruk N(1)(2)(3)(4), Lai NM(5). Author information: (1)School of Pharmacy, Monash University Malaysia, Bandar Sunway, Malaysia. (2)School of Population Health, University of Queensland, Brisbane, QLD, Australia. (3)Center of Pharmaceutical Outcomes Research (CPOR), Department of Pharmacy Practice, Faculty of Pharmaceutical Sciences, Naresuan University, Phitsanulok, Thailand. (4)School of Pharmacy, University of Wisconsin, Madison, WI, USA. (5)School of Medicine, Taylor's University, Subang Jaya, Malaysia. DOI: 10.1111/bcp.13091 PMCID: PMC5338146 PMID: 27650490 [Indexed for MEDLINE]

To identify the antidiabetic plants of Iran, a systematic review of the published literature on the efficacy of Iranian medicinal plant for glucose control in patients with type 2 diabetes mellitus was conducted. We performed an electronic literature search of MEDLINE, Science Direct, Scopus, Proquest, Ebsco, Googlescholar, SID, Cochrane Library Database, from 1966 up to June 2010. The search terms were complementary and alternative medicine (CAM), diabetes mellitus, plant (herb), Iran, patient, glycemic control, clinical trial, RCT, natural or herbal medicine, hypoglycemic plants, and individual herb names from popular sources, or combination of these key words. Available Randomized Controlled Trials (RCT) published in English or Persian language examined effects of an herb (limited to Iran) on glycemic indexes in type 2 diabetic patients were included. Among all of the articles identified in the initial database search, 23 trials were RCT, examining herbs as potential therapy for type 2 diabetes mellitus. The key outcome for antidiabetic effect was changes in blood glucose or HbA(1) c, as well as improves in insulin sensitivity or resistance. Available data suggest that several antidiabetic plants of Iran need further study. Among the RCT studies, the best evidence in glycemic control was found in Citrullus colocynthus, Ipomoea betatas, Silybum marianum and Trigonella foenum graecum.