Abstract
Recent evidence indicates that Ficus carica may exert glucose-lowering effects under diabetic conditions. However, reductions generally do not restore blood glucose to normal levels, raising questions about its reliability as an antidiabetic agent. This study aimed to systematically evaluate the glucose-lowering effects of F. carica in experimental diabetes models through meta-analysis, with additional assessments of dosage influence and comparison to glibenclamide. Relevant studies were retrieved from PubMed, Scopus, and Web of Science, including in vivo experiments on diabetic rats reporting blood glucose or insulin outcomes after F. carica intervention. Standardized mean differences (SMDs) with 95% confidence intervals (CIs) were calculated using meta-analysis based on leaf extract, dosage, and comparator treatment. F. carica leaf extract significantly reduced blood glucose compared to diabetic controls (SMD = –5.92; 95% CI [–8.13, –3.72]; p = .00001). Subgroup analyses demonstrated consistent effects at doses below 500 mg/kg BW (SMD = –8.11; 95% CI [–12.83, –3.39]; p = .0008) and above 400 mg/kg BW (SMD = –4.95; 95% CI [–7.49, –2.40]; p < .0001). Leaf extract showed no superior effect compared to glibenclamide (SMD = 2.10; 95% CI [0.91, 3.29]; p = .0006). A significant effect on insulin levels was observed in leaf extract (SMD = –3.65; 95% CI [–7.12, –0.18]; p = .04), though inconsistent effects were noted across other plant parts. In conclusion, F. carica demonstrates antidiabetic potential by reducing blood glucose in diabetic rats, but effects remain within the prediabetic range and are not superior to glibenclamide. Further research is needed to achieve normoglycemic reduction and consistent insulin effects under diabetic conditions.
Introduction
According to the International Diabetes Federation, the number of people with diabetes mellitus is projected to increase by 45% from 2024 to 2050. 1 Diabetes is commonly treated with insulin therapy and several oral antidiabetic drugs that reduce blood glucose levels. However, these treatments cannot always restore glucose to normal levels, and patients often require lifelong use. Therefore, new antidiabetic agents with better efficacy and fewer side effects are still needed. Plant-based compounds may offer a promising alternative for diabetes treatment. 2 The World Health Organization (WHO) also supports the use of herbal medicine as a complementary or alternative approach in diabetes management. 3
Ficus carica has recently been investigated for its antidiabetic potential through various in vivo studies.4,5 Findings indicate that F. carica can improve hyperglycaemia under diabetic conditions. However, several studies have shown that the reduction in blood glucose levels due to F. carica intervention still falls within the prediabetic to diabetic range.6,7 These outcomes may raise uncertainty and ambiguity regarding the potential of F. carica as a reliable antidiabetic agent.
Therefore, it is essential to conduct an evaluation based on the available evidence through systematic review and meta-analysis. To date, although several studies have reported the antidiabetic potential of F. carica, no comprehensive meta-analysis has specifically synthesized evidence from in vivo studies. Previous reports have primarily been limited to narrative reviews or individual experimental findings without quantitative integration. Furthermore, this study focuses on in vivo (animal) studies because clinical evidence in humans remains limited and insufficient for quantitative synthesis. In vivo models play a crucial role in preclinical research, allowing controlled evaluation of pharmacological effects, mechanisms of action, and dose–response relationships under diabetic conditions, and providing essential translational evidence prior to clinical trials. This approach aims to provide robust validation of the antidiabetic potential of F. carica. This evaluation aims to determine whether F. carica requires further in-depth investigation or is ready to advance into clinical trials.
Materials and Methods
Review Methodology
This meta-analysis followed the PRISMA 2020 guidelines, which give a clear and standardized method for systematic review and meta-analysis studies. The guidelines were used to ensure clarity, transparency, and accuracy in the research process. The study protocol was also registered in the PROSPERO database on July 10, 2025, and approved on July 29, 2025, with the registration number CRD420251091406 (
Eligibility Criteria
The studies included in this review met several specific criteria. They had to use an experimental design with animal models such as Wistar rats, Sprague–Dawley rats, or Mus musculus. The treatment had to be given in extract form with a clearly defined dosage, and each study needed to include both an intervention and a control group. Studies were excluded if they were not written in English, were incomplete, or did not clearly report their results.
Information Sources
Relevant studies were searched from major journal databases, including Scopus, PubMed, and Web of Science (WoS). The literature search was carried out until August 14, 2025.
Search Strategy
Search keywords were defined using both MeSH and non-MeSH terms as follows: (“Fig” OR Ficus carica) AND (“Diabetes Mellitus” OR “Hyperglycaemia” OR “Glucose Intolerance”). No publication date limits were applied, and only studies published in English were included. The collected data were saved as “PubMed Set” and “RIS” files and then imported into Mendeley to prevent data loss.
Selection Process
The study selection process was assisted by Rayyan.ai (
Data Collection Process
Data were extracted independently by two reviewers using a standardized extraction form. Extracted information included: author, year of publication, animal model, induction method, extract type and dose, duration of treatment, comparator drug (if any), and primary outcomes (blood glucose and insulin levels). Discrepancies were resolved by consensus.
Data Items (Outcomes)
The main outcomes were fasting blood glucose (FBG) and insulin levels after F. carica administration. Other extracted variables included the type of extract, treatment duration, and comparator used (e.g., glibenclamide).
Study of Risk of Bias Assessment
Risk of bias for individual studies was assessed using SYRCLE’s Risk of Bias Tool for animal studies. 8 The evaluation covered randomization, allocation concealment, blinding, completeness of data, and selective outcome reporting. Disagreements between assessors were discussed until consensus was achieved.
Effect Measures
For quantitative synthesis, the standardized mean difference (SMD) and 95% confidence intervals (CIs) were calculated for continuous outcomes (blood glucose and insulin levels). Negative SMD values indicated a glucose-lowering effect compared with controls.
Synthesis Methods
Meta-analysis was performed using a random-effects model (DerSimonian and Laird method) to account for potential heterogeneity. Statistical heterogeneity was evaluated using I 2 statistics and Cochran’s Q test. Considering the phytochemical variability among different parts of F. carica (e.g., leaves, fruit, bark, and seed oil), the meta-analysis was restricted to studies utilizing F. carica leaves, as this subgroup provided sufficient data for quantitative synthesis. Studies using other plant parts were not included in the pooled analysis due to limited data availability and were instead described qualitatively. All analyses were performed using RevMan version 5.4 (Cochrane Collaboration, London, UK). A p < .05 was considered statistically significant.
Reporting Bias Assessment
Publication bias was assessed visually using funnel plots. The overall certainty of evidence was evaluated by considering the risk of bias, consistency of results across studies, relevance of the animal models to clinical conditions, and reliability of reported data, following the code framework as “ +,” “?,” and “–”; then categorized as “Low,” “Unclear,” or “High.”
GRADE Assessment
The overall certainty of evidence across studies was assessed using the GRADE (Grading of Recommendations, Assessment, Development and Evaluations) framework adapted for preclinical animal studies, as described by Hooijmans et al. (2018). Five domains were evaluated: (a) risk of bias, informed by the results of SYRCLE’s Risk of Bias tool; (b) inconsistency, evaluated using I 2 statistics and Cochran’s Q test; (c) indirectness, reflecting the translational gap between chemically induced animal diabetes models and human Type 2 diabetes mellitus; (d) imprecision, based on the width of 95% CIs and the number of included studies; and (e) publication bias, assessed visually through funnel plots. The certainty started at “high” and was downgraded by one level for serious concerns (−1) or two levels for very serious concerns (−2) in each domain. The final certainty was categorized as high, moderate, low, or very low. 9
Results
Study Selection
The selection process for relevant studies is presented in Figure 1. The search across three databases identified 584 studies. Screening removed 61 duplicate studies. A further manual screening yielded 13 studies that were relevant and met the criteria for systematic review. However, only five of these studies provided sufficient data for statistical testing in the meta-analysis.

PRISMA Flow Diagram.
Study Characteristics and Results
The characteristics of each study that met the inclusion criteria are presented in Table 1. The potential of F. carica as an antidiabetic agent has been investigated in various countries. Most studies were conducted in India (three studies). Two studies were conducted in Turkey, while China, Indonesia, Morocco, Malaysia, Saudi Arabia, the United Arab Emirates, Iraq, and Pakistan each contributed one study.
Data Extraction Summary of Included Studies.
Thirteen studies reported the type of experimental animals used. Nine studies used the Rattus norvegicus strain Wistar, one study used R. norvegicus strain Sprague–Dawley, and two studies used M. musculus, while one study did not specify the animal strain. To induce diabetes, 10 studies used streptozotocin (STZ), while three used alloxan. Eight studies reported the STZ dose (30–150 mg/kg BW), whereas one did not. Similarly, two studies reported the alloxan dose (65 and 150 mg/kg BW), while one did not. The dose and duration of F. carica intervention also varied. The reported doses ranged from 200 to 1 g/kg BW, with one study expressing the dose in mL/kg BW. The duration of intervention ranged from 9 days to 6 weeks.
All included studies measured serum blood glucose levels, and most also assessed additional biomarkers (Table 2). These included serum insulin, body weight, lipid profile, and oxidative stress markers in organs such as the kidney, liver, and pancreas. Some studies further evaluated inflammatory parameters and sperm count. Among all assessed biomarkers, only blood glucose and insulin levels, which are treated with leaf F. carica extract, met the criteria for quantitative analysis across all studies.
Laboratory Outcome of Biomarkers.
Risk of Bias in Studies
Risk of bias was assessed across 13 included preclinical animal studies using SYRCLE’s Risk of Bias Tool, with results summarized in Table 3. No study was classified as high risk. Nine studies (69.2%) demonstrated low risk of bias, while four studies (30.8%) Ahmad et al. (2013), Arafa et al. (2020), Saleem et al. (2023), and Sharma (2022) were classified as unclear risk, primarily attributable to insufficient reporting of sequence generation (Domain 1, unclear in 9/13 studies) and allocation concealment (Domain 3, unclear in 12/13 studies). In contrast, all studies demonstrated adequate blinding of outcome assessors (Domain 7), complete outcome data reporting (Domain 8), freedom from selective reporting (Domain 9), and absence of other identifiable bias sources (Domain 10). Four studies additionally identified gaps in caregiver blinding (Domain 5) and random outcome selection (Domain 6), which may theoretically introduce performance or detection bias; however, these concerns are partially mitigated by the consistent implementation of outcome assessor blinding across all studies. Taken together, the risk of bias profile of the included evidence base is considered satisfactory for meta-analytic synthesis, though findings should be interpreted with appropriate caution given the inherent reporting limitations of preclinical research.
Risk of Bias Assessment Using the SYRCLE’s Checklist Tool.
Results of Syntheses
All parts of F. carica demonstrate potential anti-hyperglycemic properties. The data indicate that blood glucose levels in diabetic rats treated with F. carica extract were lower compared to the diabetic control group. However, this interpretation must be approached with caution. This is due to the fact that the parts of F. carica used to prepare the extracts remained heterogeneous across studies. Furthermore, a comprehensive statistical analysis could not be conducted, as the data reporting the specific parts of F. carica utilized as extracts were limited.
The induction of extracts derived from different parts of F. carica yielded varying results. Studies conducted by Ahmad et al. (2013), Saleem et al. (2023), and Irudayaraj et al. (2017) each utilized extracts from distinct parts of F. carica, namely the bark, fruit, and leaf, respectively. Diabetic rats treated with extracts derived from the bark and fruit exhibited higher blood insulin levels compared to the diabetic control group. In contrast, opposing results were observed in diabetic rats treated with the leaf extract. The blood insulin levels of rats treated with F. carica leaf extract were lower than those of the diabetic control group.
Beyond blood glucose and insulin levels, several other parameters were also affected by the administration of F. carica extract under diabetic conditions. The seed oil and bark extracts of F. carica exhibit antioxidant potential, as evidenced by their ability to reduce malondialdehyde (MDA) levels in diabetic conditions. Notably, the seed oil of F. carica shows promise in providing hepatoprotective effects against liver damage. This is supported by the observed reduction in alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activity under diabetic conditions. The fruit extract of F. carica also demonstrates potential in improving the lipid profile under diabetic conditions by reducing levels of cholesterol, triglycerides (TG), low- density lipoprotein (LDL), and very low-density lipoprotein (VLDL), while simultaneously increasing high-density lipoprotein (HDL) levels. Furthermore, F. carica fruit extract shows potential in enhancing renal filtration activity, as demonstrated by lower creatinine and urea levels compared to the diabetic control group.
Meta-analysis
Effect of Leaf F. carica Extract on Blood Glucose Level
Figure 2 illustrates the statistical analysis of the effects of leaf F. carica extract on blood glucose levels in diabetic rats. The results showed a significant effect size for leaf F. carica extract in reducing blood glucose levels (SMD = –5.92; 95% CI [–8.13, –3.72]; p = .00001). Subgroup analysis by dosage indicated that both doses below 500 mg/kg BW (SMD = –8.11; 95% CI [–12.83, –3.39]; p = .0008) and above 400 mg/kg BW (SMD = –4.95; 95% CI [–7.49, –2.40]; p = .0001) significantly lowered blood glucose compared with the control group. However, both dosage ranges reduced glucose only to the prediabetic level, without reaching the normal range (Figure 3A and 3B). It should be noted that the results of this meta-analysis demonstrate a high level of heterogeneity. This is attributed to numerous factors, including variations in dosage, extraction processes, and the solvents used during extraction. Differences in the chemical agents employed to induce diabetes across individual studies also contribute to this variability. Therefore, caution is warranted when interpreting the findings of this meta-analysis.

Forest Plot for the Pooled Standardized Mean Difference (SMD) and 95% Confidence Interval (CI) of Blood Glucose Level (mg/dL) in Diabetic Rats. D + Leaf FC: Diabetic Rats with Leaf Ficus carica Extract; D Control: Diabetic Rats Control.

Forest Plot for the Pooled Standardized Mean Difference (SMD) and 95% Confidence Interval (CI) of Blood Glucose Level (mg/dL) in Diabetic Rats (A) Leaf Ficus carica Extract at Dose <500 mg/kg BW, (B) Leaf F. carica Extract at Dose >400 mg/kg BW. D + Leaf FC: Diabetic Rats with Leaf F. carica Extract; D Control: Diabetic Rats Control.
A subgroup analysis was also performed to compare the effects of leaf F. carica extract with glibenclamide on blood glucose levels (Figure 4A–4C). The results indicated that F. carica did not reduce blood glucose more effectively than glibenclamide (SMD = 2.10; 95% CI [0.91, 3.29]; p = .0006). At doses below 500 mg/kg BW (SMD = 2.82; 95% CI [–2.66, 8,30]; p = .31) and above 400 mg/kg BW (SMD = 2.10; 95% CI [0.77, 3.42]; p = .002), F. carica similarly showed no superior effect compared with glibenclamide.

Forest Plot for the Pooled Standardized Mean Difference (SMD) and 95% Confidence Interval (CI) of Blood Glucose Level (mg/dL) in Diabetic Rats (A) Ficus carica Versus Glibenclamide, (B) F. carica Extract at Dose <500 mg/kg BW Versus Glibenclamide, (C) F. carica Extract at Dose >400 mg/kg BW Versus Glibenclamide. D + Leaf FC: Diabetic Rats With Leaf F. carica Extract; D + Glibenclamide: Diabetic Rats With Glibenclamide.
Effect of Leaf F. carica Extract on Insulin Level
Figure 5 presents the statistical results of leaf F. carica extract on insulin levels in diabetic rats. The findings indicate that leaf F. carica extract had a significant effect on insulin levels under diabetic conditions (SMD = –3.65; 95% CI [–7.12, –0.18]; p = .04).

Forest Plot for the Pooled Standardized Mean Difference (SMD) and 95% Confidence Interval (CI) of Insulin Level (mg/dL) in Diabetic Rats With Leaf Ficus carica Extract Versus D Control.
Certainty of Evidence (GRADE Assessment)
Beginning from a high certainty rating, the evidence was downgraded by a total of four levels: one level for serious risk of bias (−1), two levels for very serious inconsistency (−2), and one level for serious indirectness (−1). The overall certainty of evidence is therefore rated as Very Low (Table 4). This rating indicates that the true effect of F. carica on blood glucose levels in preclinical animal models remains highly uncertain, and that the observed effect sizes may differ substantially from the effects that would be anticipated in a human clinical population. These findings underscore the importance of cautious interpretation and highlight the need for rigorously designed clinical investigations, including standardized extract characterization, dose-escalation studies in humans, and long-term safety assessments before any therapeutic extrapolation from the preclinical evidence base can be warranted.
GRADE Assessment.
Discussion
F. carica as an Antidiabetic Agent
F. carica has been widely recognized as a plant with a rich phytochemical profile. Its major bioactive compounds include phenolic substances such as anthocyanins (cyanidin-3-O- rutinoside, cyanidin-3,5-O-diglucoside, and pelargonidin derivatives), with epicatechin reported as the most dominant phenolic compound in the fruit, while flavonoids such as myricetin, kaempferol, and quercetin are present in smaller amounts. The plant also contains tocopherols, particularly γ-tocopherol as the most abundant form, along with other seed-derived compounds including gamma-sitosterol and polyunsaturated fatty acids. Additionally, flavonoids, terpenoids, and tannins have been consistently identified across various parts of the plant, whereas saponins and alkaloids were generally absent or detected in negligible amounts.19,20 These bioactive compounds are found throughout the entire plant, including the leaves, fruits, roots, and stem bark. 19 Given this diverse phytochemical composition, a growing number of studies have investigated the potential of F. carica as a natural antidiabetic agent.21,22
All parts of F. carica extract showed hypoglycemic effects under diabetic conditions. Leaf extract was the most commonly used and produced the greatest reduction in blood glucose levels, bringing values closest to the normal range. In contrast, seed oil, fruit, and bark extracts showed weaker blood glucose-lowering effects compared to the leaf extract. The leaf fraction is particularly rich in flavonoid compounds such as tannins and quercetin, while the fruit fraction contains higher amounts of epicatechin. Seed oil, on the other hand, is predominantly composed of terpenoid compounds, especially tocopherols. 19 Each part of the F. carica extract showed a different effect on insulin levels. Leaf extract administration resulted in lower insulin levels compared to the diabetic control group. In contrast, bark and fruit extract administration produced higher insulin levels compared to the diabetic control group. These differences are likely explained by the distinct phytochemical composition of each plant part, which influences their respective antidiabetic mechanisms and potency.
The antidiabetic effects of F. carica are hypothesized to act through several mechanisms. Flavonoids in F. carica are suggested to improve tissue sensitivity to insulin, thereby enhancing glucose uptake. F. carica may also increase the expression of insulin receptor substrate 1 (IRS-1) in hepatic tissue, and this effect is likely to occur in adipose and muscle tissues as well. 23 Phenolic acids have also been reported to enhance IRS-1 expression in tissues. 24 Increased IRS-1 expression in hepatic, muscle, and adipose tissues can promote glucose uptake, resulting in decreased blood glucose levels. 25 In addition to improving tissue response to insulin, phenolic compounds, anthocyanins, and flavonoid derivatives such as epicatechin and quercetin have been reported to inhibit the activity of α-amylase and α-glucosidase enzymes and help control glucose absorption from the digestive system into the bloodstream.22,25,26
In addition to improving insulin sensitivity, F. carica is also suggested to play a role in inhibiting hepatic gluconeogenesis. This effect is indicated by reduced ALT and AST levels following F. carica administration. 27 Both enzymes are important in providing substrates for gluconeogenesis. A decrease in ALT reduces the conversion of alanine to pyruvate, while a decrease in AST limits the formation of oxaloacetate from aspartate. Consequently, gluconeogenic activity decreases, leading to reduced endogenous glucose production by the liver and improved hyperglycemia in diabetes. 28 Chlorogenic acid and quercetin, flavonoid compounds confirmed to be present in F. carica, 23 may contribute to this effect. Yang and Kang (2018) demonstrated that quercetin reduced ALT and AST levels in STZ-induced diabetic rats, 29 while Shirkhani et al. (2022) confirmed that chlorogenic acid decreased ALT and AST levels in diabetic rats. 30
Beyond enhancement of peripheral tissue insulin sensitivity, inhibition of carbohydrate-digesting enzymes, and suppression of hepatic gluconeogenesis, F. carica also demonstrates potential in protecting pancreatic β-cells from damage. These findings suggest that the glucose-lowering effect of F. carica may be predominantly mediated through insulin-independent pathways, including inhibition of intestinal α-glucosidase, enhanced GLUT4 translocation in tissues, and suppression of hepatic gluconeogenesis. However, the possibility of a partial insulin-mediated contribution cannot be entirely excluded, as evidenced by the inconsistent directional effects observed across individual studies. Future studies with standardized protocols are warranted to further elucidate the precise mechanisms underlying the antidiabetic activity of F. carica.
Although all parts of F. carica extract demonstrate potential antidiabetic properties, the observed reduction in blood glucose levels remained within the prediabetic range. This may be attributed to the complexity of the metabolic environment in diabetes, which can influence the overall antidiabetic efficacy of F. carica. Furthermore, the diabetic animal model itself represents a critical confounding factor, as chemical induction by alloxan or STZ causes extensive damage to pancreatic tissue, thereby impairing insulin synthesis and peripheral tissue response.31,32
The findings of this study indicate that F. carica extract is only effective in reducing blood glucose levels at the prediabetic stage. Nevertheless, F. carica demonstrates additional pharmacological potential that warrants consideration as an alternative herbal agent, including antioxidant, antihyperlipidemic, and anti-inflammatory properties. Hyperlipidemia also contributes to the worsening of diabetes. This condition interferes with the ability of tissues to respond to insulin signals, leading to the development of insulin resistance. 33 Reactive oxygen species (ROS) contribute significantly to the progression of diabetes. Excessive ROS levels can cause oxidative stress, leading to pancreatic β-cell damage and reducing their ability to secrete insulin. Moreover, ROS accumulation disrupts insulin signaling in target tissues through the activation of inflammatory pathways and abnormal phosphorylation of signaling proteins, thereby inducing insulin resistance. Thus, oxidative stress mediated by ROS directly contributes to impaired insulin secretion and insulin resistance, two key mechanisms in the progression of diabetes mellitus. 34 Furthermore, ROS can induce lipid peroxidation, producing byproducts such as MDA. Evidence shows that MDA can trigger inflammation and cell death, including in pancreatic cells and other tissues. 35
Polyphenolic compounds have been widely confirmed to possess antioxidant activity. Polyphenols act as antioxidants through three main mechanisms: Hydrogen Atom Transfer (HAT), by donating a hydrogen atom to stabilize free radicals; single electron transfer (SET), by transferring an electron to neutralize free radicals; and transition metal chelation (TMC), by binding to metal ions, especially Fe and Cu, thereby preventing the catalytic formation of ROS. 36 In addition, polyphenols can enhance antioxidant enzyme activity by indirectly strengthening the cellular defense system, particularly through the activation of the Nuclear factor erythroid 2-related factor 2 (Nrf2) pathway, which regulates the expression of endogenous antioxidant enzymes such as superoxide dismutase (SOD) and catalase (CAT). 37 These findings are consistent with previous studies reporting that F. carica reduces MDA levels and increases the activity of antioxidant enzymes such as SOD and CAT, most likely due to its polyphenolic content.
High blood glucose levels (hyperglycemia) can trigger chronic inflammation through the activation of inflammatory pathways, including nuclear factor kappa B (NF-κB) and inflammasomes. This activation increases the production of pro-inflammatory cytokines, such as tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6), which contribute to organ damage, insulin resistance, and the development of diabetic complications. F. carica has been shown to exhibit anti-inflammatory activity. Oktay et al. (2024) reported that administration of F. carica seed oil reduced TNF-α, IL-6, and interleukin-1 beta (IL-1β) levels under diabetic conditions. 4 The tocopherol content in F. carica plays an important role in its anti-inflammatory effects, as confirmed by previous studies. 38
Glibenclamide is an antidiabetic drug that enhances insulin granule exocytosis into the bloodstream. It induces the closure of ATP-dependent K⁺ channels, leading to intracellular K⁺ accumulation and subsequent membrane depolarization. As a result, ATP-dependent Ca 2 ⁺ channels open, allowing Ca 2 ⁺ influx, which triggers insulin secretion into the circulation. Insulin then acts as a signal for peripheral tissues to take up glucose from the blood. 39 In this study, insulin levels in diabetic rats treated with F. carica versus glibenclamide need further development. Blood glucose levels in diabetic rats treated with F. carica were not superior and appeared less effective than the glibenclamide-treated group. These findings indicate that both F. carica and glibenclamide may exert comparable effects on blood glucose regulation and insulin secretion.
Regarding long-term safety, the included studies did not systematically report adverse effects or toxicity profiles of F. carica extract, which represents a notable gap in the current evidence base. 40 In contrast, glibenclamide, which was used as the pharmacological comparator in the included studies, is a sulfonylurea agent associated with well- documented adverse effects. Prolonged use of glibenclamide has been shown to predispose patients to hypoglycemia and beta-cell exhaustion/failure.41,42 It should be noted, however, that glibenclamide remains a widely utilized antidiabetic agent, particularly in low- and middle-income countries, owing to its proven glucose-lowering efficacy, affordability, and accessibility. Nevertheless, its adverse effect profile underscores the ongoing clinical need to identify alternative agents with a more favorable safety margin. 43
Based on the subgroup analysis, F. carica leaf extract demonstrated significant antihyperglycemic effects across all dose levels examined (below 500 mg/kg and above 400 mg/kg body weight), with consistent effects observed throughout this range. To assess the clinical translatability of these doses, human equivalent doses (HED) were estimated using the FDA body surface area allometric scaling method (Km: rat = 6, mouse = 3, human = 37), assuming a standard adult body weight of 60 kg.44,45 The effective preclinical dose range of 400–500 mg/kg corresponded to HED values of approximately 1,944–4,866 mg/day substantially exceeding the 1,000–2,000 mg/day typically achievable through standardized capsule supplementation (two to four capsules at 500 mg each) and the estimated 300–2,000 mg/day deliverable through conventional F. carica leaf tea (three to four cups prepared from 2 to 5 g dried leaf, yielding 5%–10% extractable bioactive content). These findings indicate that while the antihyperglycemic effect of F. carica leaf extract is robust across the preclinical dose range, the clinically feasible human equivalent corresponds more closely to the lower tier of studied animal doses. Future dose-optimization studies in humans should therefore prioritize standardized extract formulations with verified bioavailability, rather than direct extrapolation from crude animal dose protocols.
Strengths and Limitations
This study is the first meta-analysis conducted to evaluate the potential of F. carica as an antidiabetic agent based on in vivo studies, particularly regarding its hypoglycemic effects. This represents a major strength of the present research. However, the study also has some limitations. First, the animal models used in the included studies were not uniform. Second, the plant parts used for extract preparation were heterogeneous. Third, out of 13 studies, only five studies (using leaf extract of F. carica) had sufficient data to be included in the meta-analysis. This was due to the limited availability of biomarker data regarding the antidiabetic effects of F. carica extracts derived from parts other than the leaf. Fourth, the risk of bias assessment revealed that methodological reporting quality was suboptimal in several included studies. Specifically, Domain 1 (sequence generation) and Domain 3 (allocation concealment) were frequently rated as unclear risk. These four limitations may influence the strength and consistency of this study’s findings.
The high heterogeneity observed in this meta-analysis warrants careful interpretation. Beyond methodological variability in extraction solvents and diabetic induction agents, a key confounding factor is the phytochemical heterogeneity between different parts of F. carica. As described qualitatively in this study, the leaf, fruit, bark, and seed oils each carry distinct bioactive profiles. This phytochemical variability between plant parts represents a major confounding factor that limits the generalizability of findings across studies and reinforces the decision in this meta-analysis to restrict quantitative pooling exclusively to leaf extract studies.
Prospective Study
F. carica has been shown to reduce blood glucose levels in diabetic conditions; however, the reduction only reached the prediabetic range. This highlights the need for further studies to achieve normalization of glucose levels. One potential direction is through extract modification. For example, Sa et al. (2023) reported that the addition of Au and Co metal nanoparticles to butterfly pea extract successfully lowered blood glucose levels to non-diabetic levels. 46 Furthermore, alternative extraction methods such as fermentation deserve further exploration. It has been reported that fermented F. carica fruit extract was able to reduce blood glucose levels to the normal range. 47
Conclusion
F. carica shows potential as a natural herbal agent in diabetes management. In addition, it demonstrates antioxidant, anti- lipidemic, and anti-inflammatory properties. However, further research is required to ensure its glucose-lowering effect reaches non-diabetic levels, rather than remaining only at the prediabetic stage.
Footnotes
Acknowledgements
Not applicable.
Authors’ Contribution
All authors made substantial contributions to conception and design, acquisition of data, or analysis and interpretation of data; took part in drafting the article or revising it critically for important intellectual content; agreed to submit to the current journal; gave final approval of the version to be published; and agree to be accountable for all aspects of the work. All the authors are eligible to be author as per the International Committee of Medical Journal Editors (ICMJE) requirements/guidelines.
Consent to Participate
Not applicable.
Consent for Publication
Not applicable.
Declaration of Conflicting Interests
The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Ethical Approval
This study does not involve experiments on animals or human subjects.
Funding
The authors received no financial support for the research, authorship, and/or publication of this article.
Informed Consent
Not applicable.
Use of Artificial Intelligence-assisted Tools
The authors used Rayyan.ai to help identify duplicate studies, title and abstract screening, and classification of article types during the study selection process. This approach aimed to improve time efficiency during the process of selecting eligible studies.
