Garcinia Cambogia

Previous studies have assessed how supplementing with Garcinia cambogia affects glycaemic control and liver enzyme levels; nevertheless, the results were not consistent. The study aimed to evaluate the impact of Garcinia cambogia on glycaemic control and liver enzymes through a systematic review and meta-analysis. Searches were conducted from the beginning through February 2023, using online databases (Scopus, Web of Science, PubMed, and Cochrane Library). Trials examining the impact of Garcinia cambogia on serum levels of fasting blood sugar (FBS), serum level of insulin, alanine transaminase (ALT), and aspartate transaminase (AST) in adults were included. The overall estimates and their 95% confidence intervals (CIs) were calculated using a random-effects model. This meta-analysis includes nine publications with 444 participants. The results showed that Garcinia cambogia has no significant effect on FBS (weighted mean difference (WMD): 1.02 mg/dl, 95% CI: -1.29, 3.33), insulin (WMD: -0.12 mU/L, 95% CI: -1.50, 1.25), AST (Hedges' g: -0.08, 95% CI: -0.43, 0.26), and ALT (Hedges' g: 0.27, 95% CI: -0.20, 0.73). Subgroup analysis showed that Garcinia cambogia significantly increased insulin levels in females and also increased insulin and FBS levels in those with a BMI ≥30 kg/m2. Nevertheless, the administration of Garcinia cambogia for more than 8 weeks significantly decreased insulin levels. This meta-analysis showed that supplementation with Garcinia cambogia has no significant effect on FBS, insulin, ALT, or AST levels compared with control groups; however, it seems that increasing the duration of the intervention may have a decreasing effect on insulin levels. © The Author(s) 2025.

OBJECTIVE: Several trials have examined the effect of Garcinia cambogia supplement on the weight and body composition, but their results are conflicting. This systematic review and dose-response meta-analysis was designed to determine the effect of Garcinia cambogia supplement on the obesity indices in human randomized controlled trials (RCTs). METHODS: PubMed/Medline, Scopus, Cochrane library, and Web of Science databases were searched up to 1th January, 2020, to screen relevant trials. The mean changes in the weight, body mass index (BMI), percentage of fat mass (PFM), and waist circumference (WC) from the baseline were used to conduct the present dose response meta-analysis. RESULTS: In the current study, eight trials (including 530 subjects) were included. Garcinia cambogia supplement significantly reduced the weight by -1.34 kg (95% CI: -2.62 to -0.07, P = 0.03), BMI by -0.99 kg/m2 (95% CI: -1.48 to -0.49, P < 0.001), PFM by -0.42% (95% CI: -0.77 to -0.06, P = 0.02), and WC by -4.16 cm (95% CI: -7.83 to -0.49, P = 0.02) compared with the placebo group. Dose-response analysis revealed that there is a nonlinear association between Garcinia cambogia dosage and changes in the body weight (Pnonlinearity = 0.04) and BMI (Pnonlinearity < 0.001) not PFM (Pnonlinearity = 0.68). There was no publication bias among the studies. CONCLUSION: Our results suggested that Garcinia cambogia supplement had a significant effect on the body weight, BMI, PFA, and WC as compared with the placebo.

OBJECTIVE: To evaluate the efficacy of Garcinia cambogia (hydroxy citric acid) alone or in combination with Silodosin on the clinical outcomes of lower urinary tract symptoms/Benign prostatic hyperplasia (LUTS/BPH). METHODS: A prospective, randomized, controlled, double-blind study conducted on patients with LUTS/BPH. Eligible patients were assigned randomly to one of three groups. Group A (33 patients) received Silodosin, 8 mg, once daily. Group B (35 patients) received Garcinia extract 500 mg TID. Group C (36 patients) received the combination of Silodosin, plus Garcinia extract. All participants were assessed for the changes in; the maximum urinary flow rate (Qmax), International Prostate Symptom Score (IPSS), Post-Void Residual (PVR), prostate volume (PV), and serum Prostatic Specific Antigen (PSA) levels, at the baseline and after 12 weeks of treatment. RESULTS: The baseline data regarding Qmax, IPSS, PVR, PV, and PSA showed non-significant differences between the three groups. After 12 weeks of treatment, all groups showed a significant improvement in both Qmax and IPSS (P >.001) and group C showed the best improvement. The PVR was significantly reduced in all groups (P >.001). The PV was significantly increased in group A (P = .006), whereas it was significantly reduced in groups B and C (P >.001). The PSA showed a non-significant increase in group A (P = .625), while it was significantly decreased in groups B and C (P >.001). CONCLUSION: Treatment with Garcinia extract, especially in combination with Silodosin, may improve the Qmax, IPSS, PVR, PV, and PSA in patients with LUTS/BPH without any clinical significant adverse effects.

The objective of the present study was to examine the effects of hydroxy citric acid (HCA) extracts from Garcinia cambogia on metabolic, atherogenic and inflammatory biomarkers in obese women with non-alcoholic fatty liver disease (NAFLD). The present clinical trial was carried out on 40 overweight/obese women with NAFLD. The patients were randomly allocated into either the "HCA group" (receiving calorie-restricted diet (-700 kcal d-1) accompanied by HCA tablets) and the "control group" (receiving only calorie-restricted diet) for eight weeks. Weight, height, body mass index (BMI), and waist circumference (WC) were measured. Fasting blood sugar (FBS), lipid profile, liver enzymes, as well as inflammatory biomarkers were determined at baseline and after the intervention. Dietary intake was assessed at baseline and at the end of the trial and food intake data were analyzed by the Nutritionist IV software. Results showed a decrease in energy and macronutrient intake in both groups (p < 0.05). Weight, BMI, WC, and hip circumference as well as FBS, triglyceride (TG), low-density lipoprotein cholesterol (LDL-C) decreased and high-density lipoprotein cholesterol (HDL-C) increased significantly in the HCA group (p < 0.05). There were also significant reductions in WC, FBS, TG, total cholesterol, LDL-C in the control group while inter-group changes in FBS, TG, LDL-C and HDL-C were statistically significant. Although atherogenic indices reduced significantly in both groups, inter-group comparison revealed that the HCA group showed greater decrease in the TG/HDL-C ratio than the control group (p = 0.004). Other atherogenic indices including TC/HDL-C and non-HDL-C/HDL-C ratio showed greater reduction in the control versus HCA group (p < 0.01). Some inflammatory factors were reduced in the HCA group; however, no significant within- or between-group differences were revealed post-intervention. Our results indicated that HCA supplementation plus calorie-restricted diet could improve some metabolic factors without any significant effect on inflammation in patients with NAFLD.

Garcinia cambogia extract (GCE)/(-) - hydroxycitric acid (HCA) has been identified as a potential antiobesity agent. However, controversial clinical trial results have been published on its biological effect and poor pharmacokinetic (PK) information increases its dubious efficacy. The aim of this study was to determine the main PK parameters of GCE/HCA in healthy women, and to evaluate food effects on HCA absorption. Healthy women ages 21-41 years with body mass index (BMI; kg/m2) 20.29-25.82 participated in a phase I, open-label, randomized, single-dose, cross-over study. In the fasted- and fed-conditions subjects received 1500/750 mg of GCE/HCA under 8 h of fasting. In the fed-period was given a high calorie breakfast (~600 calories) after dosing. Plasma HCA concentrations were substantially reduced in fed-state. Peak plasma concentration (Cmax) and area under the curve of time-concentration (AUC0-10h) were 3-fold and 2-fold lower (p < 0.001, 0.01) in fed-condition, respectively. Higher volume of distribution (Vd/F) and clearance (Cl/F) were achieved in fed state, probably due to the lower fraction (F) of HCA absorbed induced by food effect. Large inter-individual variations were observed for the main pharmacokinetics parameters in both periods. These findings suggest that HCA might suffer an active absorption uptake and intense adsorption on food.

Garcinia cambogia supplements are widely used for weight loss. Knowing that epilepsy patients are at greater risk of developing overweight/obesity, the investigation of herb-drug interactions involving antiepileptic drugs of narrow therapeutic index is fully justified. This work was planned to assess potential pharmacokinetic-based interactions between G. cambogia extract and lamotrigine (LTG) through two independent pharmacokinetic studies. In the first study (co-administration study), rats were orally co-administered with a single-dose of G. cambogia extract (821 mg/kg) and LTG (10 mg/kg). In the second study (pre-treatment study), rats were orally pre-treated for 14 days with G. cambogia extract (821 mg/kg/day), being LTG administered (10 mg/kg) on the 15th day. Rats of the control groups received water instead of the extract. Following LTG administration, blood samples were collected until 96 h post-dose, and plasma LTG concentrations were determined and submitted to a non-compartmental analysis. Globally, no statistically significant effects were identified in the co-administration study of G. cambogia extract and LTG. In the 14-day pre-treatment study, a statistically significant decrease in the rate of systemic exposure to LTG and an increase of apparent volume of distribution were found. Even so, a minor or no clinical impact is expected from the administration of G. cambogia dietary supplements and LTG.

Rising rates of obesity across the globe have been associated with an increase in the use of herbal preparations for weight control. However, the mechanisms of action for these substances are often not known, as is the potential for interaction with other herbal preparations or prescription pharmaceutical drugs. To investigate the reported efficacy and safety of herbal weight loss preparations, we conducted a review of the literature focusing on herbs that are most commonly used in weight loss preparations, specifically, Garcinia cambogia, Camellia sinensis, Hoodia gordonii, Citrus aurantium and Coleus forskohlii. There was no clear evidence that the above herbal preparations would cause sustained long-term weight loss in humans in the long term. Serious illness and even death have occasionally resulted from the use of herbal weight loss preparations. Few clinical trials have been undertaken to evaluate the efficacy and/or safety of herbal weight loss preparations. In addition, potential issues of herb-herb and herb-drug interactions are often not considered. Regulation of these products is much less rigorous than for prescription medications, despite documented cases of associated hepatotoxicity.

Comment in Med J Aust. 2017 Aug 7;207(3):134. doi: 10.5694/mja17.00153. Med J Aust. 2017 Aug 7;207(3):134. doi: 10.5694/mja17.00195. Med J Aust. 2017 Aug 7;207(3):134. doi: 10.5694/mja17.00163. Traditional herbal products are widely used in Australia to treat a broad range of conditions and diseases. It is popularly believed that these products are safer than prescribed drugs. While many may be safe, it is worrying that the specific effects and harmful interactions of a number of their components with prescription medications is not well understood. Some traditional herbal preparations contain heavy metals and toxic chemicals, as well as naturally occurring organic toxins. The effects of these substances can be dire, including acute hepatic and renal failure, exacerbation of pre-existing conditions and diseases, and even death. The content and quality of herbal preparations are not tightly controlled, with some ingredients either not listed or their concentrations recorded inaccurately on websites or labels. Herbal products may also include illegal ingredients, such as ephedra, Asarum europaeum (European wild ginger) and endangered animal species (eg, snow leopard). An additional problem is augmentation with prescription medications to enhance the apparent effectiveness of a preparation. Toxic substances may also be deliberately or inadvertently added: less expensive, more harmful plants may be substituted for more expensive ingredients, and processing may not be adequate. The lack of regulation and monitoring of traditional herbal preparations in Australia and other Western countries means that their contribution to illness and death is unknown. We need to raise awareness of these problems with health care practitioners and with the general public.

High aminotransferases and prolonged prothrombin time on entering our liver unit were revealing parenchymal collapse for this 45-year-old obese woman; treatment failure led her to death. Autoimmunity, paracetamol use, alcoholism, and Wilson's disease were all excluded as causes. Because of chronic asthma, she had been receiving a leukotriene receptor antagonist (montelukast) for 5 years before the current presentation; 1 week before onset she had had 1 week of treatment with two dietary supplements for weight control; one of these included Garcinia Cambogia, a possible cause of two recent cases of hepatitis in the USA; in addition, both formulas contained a citrus derivative that interferes cytochrome functions. We speculate on a causal relationship between the assumption of the additives and the fatal hepatitis and envisage a synergy between the additives and montelukast, which per se has well been studied as a hepatotoxic drug. Despite the speculative nature of this presentation, we believe the warning may serve to focus attention on the uncontrolled escalation of food additives going on in these days.

Glycogen stored in skeletal muscle is the main fuel for endurance exercise. The present study examined the effects of oral hydroxycitrate (HCA) supplementation on post-meal glycogen synthesis in exercised human skeletal muscle. Eight healthy male volunteers (aged 22·0 (se 0·3) years) completed a 60-min cycling exercise at 70-75 % VO₂max and received HCA or placebo in a crossover design repeated after a 7 d washout period. They consumed 500 mg HCA or placebo with a high-carbohydrate meal (2 g carbohydrate/kg body weight, 80 % carbohydrate, 8 % fat, 12 % protein) for a 3-h post-exercise recovery. Muscle biopsy samples were obtained from vastus lateralis immediately and 3 h after the exercise. We found that HCA supplementation significantly lowered post-meal insulin response with similar glucose level compared to placebo. The rate of glycogen synthesis with the HCA meal was approximately onefold higher than that with the placebo meal. In contrast, GLUT4 protein level after HCA supplementation was significantly decreased below the placebo level, whereas expression of fatty acid translocase (FAT)/CD36 mRNA was significantly increased above the placebo level. Furthermore, HCA supplementation significantly increased energy reliance on fat oxidation, estimated by the gaseous exchange method. However, no differences were found in circulating NEFA and glycerol levels with the HCA meal compared with the placebo meal. The present study reports the first evidence that HCA supplementation enhanced glycogen synthesis rate in exercised human skeletal muscle and improved post-meal insulin sensitivity.

OBJECTIVE: The observed impacts of Garcinia cambogia (GC) on serum leptin indicate inconsistency. We performed a systematic review and meta-analysis on randomized controlled trials (RCTs) to evaluate the effectiveness of GC on leptin levels. METHODS: A thorough literature search was carried out using different online databases, including Scopus, Web of Science, PubMed, and Google Scholar, until May 25, 2024. Using random effects, weighted mean differences (WMDs) and corresponding 95 % confidence intervals (CIs) were computed. Standard procedures were followed to account for publication bias, study quality, and statistical heterogeneity. RESULTS: In this meta-analysis, a total of eight eligible trials with 330 participants were ultimately included. Quality assessment showed that half of the included trials were considered to have fair quality, while the other half were deemed to have poor quality. Our analysis, with no indication of publication bias, showed a significantly decreased effect of GC on leptin compared with the placebo (WMD: -5.01 ng/ml; 95 % CI: -9.22 to -0.80, p = 0.02). However, significant heterogeneity was detected between studies (I2 =93.5 %, p < 0.001). The Hartung-Knapp adjustment did not affect our results. Subgroup analysis revealed that GC consumption represents the most effects in trials with sample size ≥ 50 (WMD: -3.63 ng/ml; 95 % CI [-5.51, -1.76], p < 0.001), and mean age of participants ≥ 30 years (WMD: -7.43 ng/ml; 95 % CI [-9.31, -5.56], p < 0.001). CONCLUSIONS: The findings of the present study showed that leptin levels might decline following GC administration. REGISTRATION NUMBER: CRD42023486370.

Garcinia cambogia (GC) has antioxidant, anticancer, antihistamine, and antimicrobial properties. To determine the effect of GC on lipid profiles, a systematic review and meta-analysis was carried out. Up to February 9, 2023, six electronic databases (Web of Science, Cochrane Library, Embase, PubMed, Scopus, and Google Scholar) were searched at any time without limitations. Trials examining the impact of GC on serum levels of total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol (HDL-C) in adults were included. The total effect was shown as a weighted mean difference (WMD) and 95% confidence interval (CI) in a random-effects meta-analysis approach. This systematic review and meta-analysis included 14 trials involving 623 subjects. Plasma levels of TC (WMD: -6.76 mg/dL; CI: -12.39 to -0.59, p-value = 0.032), and TG (WMD: -24.21 mg/dL; CI: -37.84 to -10.58, p < 0.001) were significantly reduced after GC use, and plasma HDL-C (WMD: 2.95 mg/dL; CI: 2.01 to 3.89, p < 0.001) levels increased. low-density lipoprotein cholesterol levels (WMD: -1.15 mg/dL; CI: -16.08 to 13.78, p-value = 0.880) were not significantly affected. The effects of lowering TC and TG were more pronounced for periods longer than 8 weeks. Consuming GC has a positive impact on TC, TG, and HDL-C concentrations. The limitations of this study include the short duration of analyzed interventions and significant heterogeneity. Nevertheless, it is imperative to conduct well-structured, and high-quality long-term trials to comprehensively evaluate the clinical effectiveness of GC on lipid profile, and validate these findings. © 2023 John Wiley & Sons Ltd.

AIM: To update the available evidence on the efficacy and safety of complementary medicines to assist in weight loss by conducting a systematic review and meta-analysis of herbal medicines for weight loss. METHODS: Four electronic databases (Medline, Embase, CINAHL and Web of Science) were searched from inception until August 2018. A total of 54 randomized placebo-controlled trials of healthy overweight or obese adults were identified. Meta-analyses were conducted for herbal medicines with ≥4 studies available. Weight differences of ≥2.5 kg were considered clinically significant. RESULTS: As a single agent, only Phaseolus vulgaris resulted in a statistically significant weight loss compared to placebo, although this was not considered clinically significant. No effect was seen for Camellia sinensis or Garcinia cambogia. Statistically, but not clinically, significant differences were observed for combination preparations containing C. sinensis, P. vulgaris or Ephedra sinica. Of the herbal medicines trialled in ≤3 randomized controlled trials, statistically and clinically significant weight loss compared to placebo was reported for Irvingia gabonensis, Cissus quadrangularis, and Sphaeranthus indicus combined with Garcinia mangostana, among others, but these findings should be interpreted cautiously because of the small number of studies, generally poor methodological quality, and poor reporting of the herbal medicine interventions. Most herbal medicines appeared safe for consumption over the short duration of the studies (commonly ≤12 weeks). Some warrant further investigation to determine effect size, dosage and long-term safety. CONCLUSION: There is currently insufficient evidence to recommend any of the herbal medicines for weight loss included in the present review. © 2020 John Wiley & Sons Ltd.

Obesity is a medical situation in which excess body fat has gathered because of imbalance between energy intake and energy expenditure. In spite of the fact that the variety of studies are available for obesity treatment and management, its "globesity" still remains a big challenge all over the world. The current systematic review and meta-analysis aimed to evaluate the efficacy, safety, and mechanisms of effective herbal medicines in the management and treatment of obesity and metabolic syndrome in human. We systematically searched all relevant clinical trials via Web of Science, Scopus, PubMed, and the Cochrane database to assess the effects of raw or refined products derived from plants or parts of plants on obesity and metabolic syndrome in overweight and obesity adult subjects. All studies conducted by the end of May 2019 were considered in the systematic review. Data were extracted independently by two experts. The quality assessment was assessed using Consolidated Standards of Reporting Trials checklist. The main outcomes were anthropometric indices and metabolic syndrome components. Pooled effect of herbal medicines on obesity and metabolic syndrome were presented as standardized mean difference (SMD) and 95% confidence interval (CI). A total of 279 relevant clinical trials were included. Herbals containing green tea, Phaseolus vulgaris, Garcinia cambogia, Nigella sativa, puerh tea, Irvingia gabonensis, and Caralluma fimbriata and their active ingredients were found to be effective in the management of obesity and metabolic syndrome. In addition, C. fimbriata, flaxseed, spinach, and fenugreek were able to reduce appetite. Meta-analysis showed that intake of green tea resulted in a significant improvement in weight ([SMD]: -0.75 [-1.18, -0.319]), body mass index ([SMD]: -1.2 [-1.82, -0.57]), waist circumference ([SMD]: -1.71 [-2.66, -0.77]), hip circumference ([SMD]: -0.42 [-1.02, -0.19]), and total cholesterol, ([SMD]: -0.43 [-0.77, -0.09]). In addition, the intake of P. vulgaris and N. sativa resulted in a significant improvement in weight ([SMD]: -0.88, 95 % CI: [-1.13, -0.63]) and triglyceride ([SMD]: -1.67, 95 % CI: [-2.54, -0.79]), respectively. Hig

OVERVIEW: As obesity has reached epidemic proportions, the management of this global disease is of clinical importance. The availability and popularity of natural dietary supplements for the treatment of obesity has risen dramatically in recent years. AIMS: The aim of this paper was to assess the current evidence of commonly available natural supplements used to suppress appetite for obesity control and management in humans using a systematic search of clinical trials meeting an acceptable standard of evidence. METHODS: The electronic databases PubMed, Web of Science, Google Scholar, ScienceDirect, and MEDLINE with full text (via EBSCOHost) were accessed during late 2012 for randomized controlled clinical trials (RCTs) using natural plant extracts as interventions to treat obesity through appetite regulation. A quality analysis using a purpose-designed scale and an estimation of effect size, where data were available, was also calculated. The inclusion criteria included the following: sample participants classified as overweight or obese adults (aged 18-65 years), randomized, double blind, controlled design, suitable placebo/control intervention, sample size >20, duration of intervention >2 weeks, have measurable outcomes on appetite or food intake and anthropometry, and full paper in English. RESULTS: There were 14 studies that met the inclusion criteria. The findings from published double blind RCTs revealed mostly inconclusive evidence that plant extracts are effective in reducing body weight through appetite suppression. Caralluma fimbriata extract and a combination supplement containing Garcinia cambogia plus Gymnema sylvestre were the only exceptions. CONCLUSION: According to the findings from this systematic review, the evidence is not convincing in demonstrating that most dietary supplements used as appetite suppressants for weight loss in the treatment of obesity are effective and safe. A balance between conclusive findings by double blind RCTs and advertisement is required to avoid safety concerns and dissatisfaction from consumers.

OBJECTIVE: The high demand for obesity treatment and conventional therapies' lack of effectiveness increases the use of alternative products. This study was aimed at assessing evidence from randomised clinical trials regarding the effectiveness of alternative weight-loss products' ingredients. METHODS: A survey was conducted in Ensenada, Baja California, to assess the frequency of consuming alternative products used for weight reduction. The ingredients in the products most in demand were included in this review. The Pubmed database was searched for all randomised clinical trial papers including these ingredients and assessing weight loss. RESULTS: Thirty-six percent of the subjects questioned had used alternative methods for weight-loss, 83% of them being women. The most frequently used products were shakes, tea, pills and flaxseed/linseed. Sixteen randomised clinical trials using four ingredients were used: Garcinia cambogia, green tea, L-carnitina and flaxseed. Only two studies (green tea and Garcinia cambogia) showed significant weight-loss (25%) amongst control and experimental groups. There was no significant difference between the groups in the studies regarding L-carnitina and flaxseed. CONCLUSIONS: There is a lack of evidence regarding quality studies justifying the use of alternative products for weight loss.

Comment in Obes Rev. 2005 May;6(2):89-92. doi: 10.1111/j.1467-789x.2005.00197.x. Herbal weight-loss supplements are marketed with claims of effectiveness. Our earlier systematic review identified data from double-blind, randomized controlled trials for a number of herbal supplements. The aim of this systematic review was to assess all clinical evidence of adverse events of herbal food supplements for body weight reduction for which effectiveness data from rigorous clinical trials exist. We assessed Ephedra sinica, Garcinia cambogia, Paullinia cupana, guar gum, Plantago psyllium, Ilex paraguariensis and Pausinystalia yohimbe. Literature searches were conducted on Medline, Embase, Amed and The Cochrane Library. Data were also requested from the spontaneous reporting scheme of the World Health Organization. We hand-searched relevant medical journals and our own files. There were no restrictions regarding the language of publication. The results show that adverse events including hepatic injury and death have been reported with the use of some herbal food supplements. For herbal ephedra and ephedrine-containing food supplements an increased risk of psychiatric, autonomic or gastrointestinal adverse events and heart palpitations has been reported. In conclusion, adverse events are reported for a number of herbal food supplements, which are used for reducing body weight. Although the quality of the data does not justify definitive attribution of causality in most cases, the reported risks are sufficient to shift the risk-benefit balance against the use of most of the reviewed herbal weight-loss supplements. Exceptions are Garcinia cambogia and yerba mate, which merit further investigation.

BACKGROUND: Compliance with conventional weight-management programs is notoriously poor, and a plethora of over-the-counter slimming aids are sold with claims of effectiveness. OBJECTIVE: The objective of the study was to assess the evidence from rigorous clinical trials, systematic reviews, and meta-analyses on the effectiveness of dietary supplements in reducing body weight. DESIGN: The study was a systematic review. Literature searches were conducted on Medline, Embase, Amed, Cinahl, and the Cochrane Library until March 2003. Hand searches of medical journals, the authors' own files, and bibliographies of identified articles were conducted. There were no restrictions regarding the language of publication. The screening of studies, selection, validation, data extraction, and the assessment of methodologic quality were performed independently by the 2 reviewers. To be included, trials were required to be randomized and double-blind. Systematic reviews and meta-analyses of dietary supplements were included if they were based on the results of randomized, double-blind trials. RESULTS: Five systematic reviews and meta-analyses and 25 additional trials were included and reviewed. Data on the following dietary supplements were identified: chitosan, chromium picolinate, Ephedra sinica, Garcinia cambogia, glucomannan, guar gum, hydroxy-methylbutyrate, plantago psyllium, pyruvate, yerba maté, and yohimbe. The reviewed studies provide some encouraging data but no evidence beyond a reasonable doubt that any specific dietary supplement is effective for reducing body weight. The only exceptions are E. sinica- and ephedrine-containing supplements, which have been associated with an increased risk of adverse events. CONCLUSIONS: The evidence for most dietary supplements as aids in reducing body weight is not convincing. None of the reviewed dietary supplements can be recommended for over-the-counter use.