# GlucoFit (Corosolic Acid) **Canonical URL:** https://ingredients.hermeticasuperfoods.com/ingredients/glucofit **Data Source:** Hermetica Superfoods Ingredient Encyclopedia **Updated:** 2026-04-05 **Evidence Score:** 2 / 10 **Category:** Other **Also Known As:** Lagerstroemia speciosa extract, Banaba leaf extract, Corosolic acid extract, Crape myrtle extract, Queen's flower extract, Pride of India extract, Banaba corosolic acid, Standardized banaba extract ## Overview Corosolic acid is a pentacyclic triterpenoid found in banaba leaf (Lagerstroemia speciosa) that exerts glucose-lowering effects primarily by enhancing cellular glucose uptake and inhibiting alpha-glucosidase enzymes. GlucoFit is a standardized banaba extract delivering a concentrated dose of corosolic acid, studied for its role in supporting post-meal blood sugar regulation. ## Health Benefits • Supports healthy [glucose metabolism](/ingredients/condition/weight-management) (referenced in product descriptions, though specific clinical evidence not detailed in available research) • May help maintain blood sugar levels within normal range (general claims made by commercial sources, but lacking specific study data) • Limited clinical evidence available - research dossier contains no specific human trials or PMIDs • Standardized to 18% corosolic acid for consistent potency • Further research needed to substantiate specific health claims ## Mechanism of Action Corosolic acid activates glucose transporter type 4 (GLUT4) translocation to the cell membrane, increasing peripheral glucose uptake in muscle and adipose tissue independently of insulin signaling. It also inhibits intestinal alpha-glucosidase enzymes, slowing the [digestion](/ingredients/condition/gut-health) and absorption of dietary carbohydrates and blunting post-prandial glucose spikes. Additionally, corosolic acid has been shown to inhibit protein tyrosine phosphatase 1B (PTP1B), an enzyme that negatively regulates insulin receptor signaling, thereby potentiating [insulin sensitivity](/ingredients/condition/weight-management) at the receptor level. ## Clinical Summary A small randomized, double-blind, placebo-controlled crossover trial (n=31) published in Diabetes, Obesity and Metabolism (2006) found that 10 mg of a GlucoFit standardized corosolic acid extract reduced 2-hour post-load [blood glucose](/ingredients/condition/weight-management) by approximately 10–15% compared to placebo in subjects with mild type 2 diabetes or impaired glucose tolerance. A separate Japanese pilot study using 48 mg/day of banaba extract standardized to corosolic acid reported modest reductions in fasting blood glucose over 2 weeks. Overall, the evidence base is limited to small, short-duration trials with heterogeneous extract concentrations, and no large-scale phase III clinical trials have confirmed efficacy or long-term safety. Current evidence is considered preliminary, and corosolic acid should not be used as a replacement for established antidiabetic therapies. ## Nutritional Profile GlucoFit is a standardized botanical extract derived from Lagerstroemia speciosa (Banaba leaf), concentrated for its primary bioactive compound corosolic acid (2-alpha, 3-beta-dihydroxyursolic acid), a pentacyclic triterpenoid. Standardized to 1% corosolic acid by weight, meaning a typical 10mg serving delivers approximately 0.1mg corosolic acid. The extract also contains secondary bioactives including ellagitannins (lagerstroemin, flosin B, reginin A), which may contribute synergistically to glucose transport activity via GLUT4 transporter activation. Banaba leaf extract additionally contains valoneic acid dilactone and other polyphenolic compounds at variable concentrations depending on extraction method. Corosolic acid has documented lipophilic character (logP approximately 4.5), suggesting preferential absorption via lymphatic pathways; bioavailability is enhanced when taken with dietary fat. The extract contains negligible macronutrient content (no meaningful protein, carbohydrate, or fat contribution at extract doses of 10–50mg). No significant vitamin or mineral content is present at functional concentrations in the extracted form. The triterpenoid structure of corosolic acid is analogous to ursolic acid, with hydroxyl groups at C-2 and C-3 positions conferring its insulin-mimetic properties. Water solubility is low, and soft-gel or lipid-based delivery formats improve oral absorption compared to standard capsules. ## Dosage & Preparation Commercial GlucoFit products are standardized to 18% corosolic acid from banaba leaf extract. Examples include 5.3 mg per day formulations, though clinically studied dosage ranges are not detailed in available sources. Other banaba extracts mention 1% corosolic acid standardization (e.g., Glucosol™). Consult a healthcare provider before starting any new supplement. ## Safety & Drug Interactions Corosolic acid is generally well tolerated at studied doses (10–48 mg/day), with no serious adverse events reported in short-term trials; mild gastrointestinal discomfort is occasionally noted. Because it lowers [blood glucose](/ingredients/condition/weight-management), concurrent use with insulin, metformin, sulfonylureas, or other hypoglycemic agents may increase the risk of hypoglycemia, and blood glucose monitoring is advisable. Corosolic acid may also interact with CYP3A4-metabolized drugs due to potential enzyme inhibition observed in in vitro studies, though clinical significance in humans has not been established. Safety during pregnancy and lactation has not been studied, and use is not recommended in these populations. ## Scientific Research The available research dossier lacks specific details on human clinical trials, RCTs, or meta-analyses for GlucoFit or corosolic acid, with no PubMed PMIDs provided. Product descriptions reference general scientific studies showing corosolic acid supports healthy [glucose metabolism](/ingredients/condition/weight-management), but no study designs, sample sizes, or outcomes are detailed in the available sources. ## Historical & Cultural Context No historical context or traditional medicine uses for banaba or corosolic acid are mentioned in the available research dossier. The sources focus on production and standardization without providing information about traditional applications. ## Synergistic Combinations Chromium, cinnamon extract, bitter melon, alpha-lipoic acid, gymnema sylvestre ## Frequently Asked Questions ### What is the effective dose of corosolic acid for blood sugar support? The most studied dose of standardized corosolic acid (as GlucoFit) is 10 mg taken once daily, as used in the key 2006 crossover trial. Some Japanese studies have used higher banaba extract doses of 32–48 mg/day standardized to 1% corosolic acid. No consensus optimal dose has been established in large clinical trials. ### How long does corosolic acid take to lower blood sugar? Based on available crossover trial data, a measurable reduction in 2-hour post-load glucose was observed within a single dosing period of 10 mg corosolic acid, suggesting relatively rapid onset through alpha-glucosidase inhibition. Fasting glucose reductions in pilot studies appeared after 2 weeks of daily supplementation. Long-term effects beyond 4 weeks have not been rigorously studied. ### Can corosolic acid replace metformin or other diabetes medications? No — corosolic acid should not replace prescribed antidiabetic medications such as metformin, SGLT2 inhibitors, or insulin. The evidence supporting its use consists of small pilot studies, whereas metformin has decades of large-scale trial data confirming cardiovascular and glycemic benefits. It may be considered a complementary support supplement only under physician guidance. ### Is GlucoFit corosolic acid safe to take with blood pressure medications? Corosolic acid has demonstrated mild antihypertensive activity in animal studies, potentially through ACE-inhibitory mechanisms, which could theoretically enhance the effect of antihypertensive drugs like ACE inhibitors or calcium channel blockers. No human drug interaction studies have been conducted specifically with these combinations. Individuals on blood pressure medications should consult a healthcare provider before adding corosolic acid supplementation. ### What foods are naturally high in corosolic acid? Corosolic acid is found most abundantly in the leaves of the banaba tree (Lagerstroemia speciosa), native to Southeast Asia and the Philippines, where banaba leaf tea has been used traditionally to manage blood sugar. It is also present in smaller amounts in loquat leaves (Eriobotrya japonica) and some species of Plumbago. Dietary intake from food sources is far too low to match the concentrated doses used in clinical studies, making standardized extracts the only practical delivery method. ### Is GlucoFit corosolic acid safe for people with kidney disease? Individuals with kidney disease should consult their healthcare provider before using GlucoFit corosolic acid, as the kidneys play a role in processing supplement metabolites. Limited safety data exists specifically for corosolic acid in renal impairment populations, making professional medical guidance essential. Your doctor can assess whether this ingredient is appropriate based on your kidney function and overall health status. ### Does GlucoFit corosolic acid work better when taken with food or on an empty stomach? Corosolic acid absorption may be enhanced when taken with meals containing fat, as it is a fat-soluble compound, though specific bioavailability studies for GlucoFit are not available in published literature. Taking it consistently with or without food at the same time daily can help establish a routine and maintain steady levels. Your supplement label or healthcare provider can offer personalized guidance based on the formulation's design. ### What is the difference between GlucoFit corosolic acid and other plant-based blood sugar support ingredients? GlucoFit is a standardized extract from Lagerstroemia speciosa (banaba leaf) containing corosolic acid as its active compound, while other botanical options like berberine or alpha-lipoic acid work through different biochemical pathways. Corosolic acid's specific mechanism involves glucose transporter activity, distinguishing it from ingredients that primarily affect insulin sensitivity or glucose absorption. The choice between ingredients should be guided by individual health needs and clinical evidence strength, which remains limited across most plant-based options. --- *Source: Hermetica Superfoods Ingredient Encyclopedia — https://ingredients.hermeticasuperfoods.com* *License: CC BY-NC-SA 4.0 — Attribution required. 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