Gynostemma

• Adaptogenic properties
• Antioxidant activity
• Cardiovascular health support
• Metabolic regulation

• Immune system modulation
• Neuroprotective effects
• Anti-inflammatory properties
• Liver protection
• Stress resistance enhancement

Gynostemma pentaphyllum (jiaogulan) exerts its biological effects through multiple mechanisms, primarily attributed to its rich content of triterpenoid saponins called gypenosides, which share structural similarities with ginsenosides found in Panax ginseng. Over 180 different gypenosides have been identified, contributing to the herb’s diverse pharmacological activities. The primary mechanism underlying Gynostemma’s adaptogenic effects is its ability to modulate the hypothalamic-pituitary-adrenal (HPA) axis, helping the body maintain homeostasis under stress. Gypenosides regulate cortisol levels and enhance adrenal function, allowing for improved stress response without the depleting effects associated with stimulants.

Gynostemma demonstrates potent antioxidant activity through multiple pathways. It directly neutralizes reactive oxygen species (ROS) and reactive nitrogen species (RNS), protecting cells from oxidative damage. More importantly, it enhances endogenous antioxidant defenses by increasing the activity and expression of antioxidant enzymes including superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase. This occurs primarily through activation of the Nrf2 (Nuclear factor erythroid 2-related factor 2) pathway, a master regulator of cellular antioxidant responses.

In the context of cardiovascular protection, Gynostemma improves endothelial function by increasing the production of nitric oxide (NO), a potent vasodilator. This occurs through multiple mechanisms, including increased expression and activity of endothelial nitric oxide synthase (eNOS) and protection of NO from degradation by free radicals. Gynostemma also improves lipid metabolism, reducing total cholesterol, triglycerides, and low-density lipoprotein (LDL) levels while increasing high-density lipoprotein (HDL) cholesterol. These lipid-regulating effects are partially mediated through modulation of the expression of key enzymes involved in cholesterol metabolism, including HMG-CoA reductase and LDL receptor.

For metabolic regulation, Gynostemma activates AMP-activated protein kinase (AMPK), a cellular energy sensor that plays a crucial role in glucose and lipid metabolism. AMPK activation leads to increased glucose uptake in skeletal muscle, reduced hepatic glucose production, and enhanced fatty acid oxidation. These effects contribute to improved insulin sensitivity and glucose tolerance. Certain gypenosides have been shown to act as PPAR-γ (peroxisome proliferator-activated receptor gamma) agonists, further enhancing insulin sensitivity and glucose metabolism.

In the context of immune modulation, Gynostemma exhibits bidirectional effects, enhancing immune function in immunocompromised states while suppressing excessive immune responses in inflammatory conditions. It increases the activity of natural killer (NK) cells and macrophages while modulating cytokine production, reducing pro-inflammatory cytokines such as TNF-α, IL-1β, and IL-6 while increasing anti-inflammatory cytokines like IL-10. This immunomodulatory effect is partially mediated through inhibition of the NF-κB (nuclear factor kappa-light-chain-enhancer of activated B cells) signaling pathway. For neuroprotection, Gynostemma protects neurons from oxidative stress and excitotoxicity through multiple mechanisms.

It enhances the expression of neurotrophic factors, including brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF), which promote neuronal survival and differentiation. Additionally, Gynostemma modulates neurotransmitter systems, particularly dopamine and serotonin, which may contribute to its cognitive-enhancing and mood-stabilizing effects. In the context of liver protection, Gynostemma inhibits hepatocyte apoptosis induced by various hepatotoxins, reduces lipid peroxidation in liver tissue, and enhances liver detoxification capacity by increasing glutathione levels and phase II detoxification enzyme activity. Additionally, it improves liver microcirculation and reduces inflammatory infiltration in liver tissue.

At the molecular level, Gynostemma influences gene expression through epigenetic mechanisms, including modulation of microRNA expression and histone modifications. It affects cell signaling pathways involved in cell survival, proliferation, and differentiation, including MAPK, PI3K/Akt, and Wnt signaling. These diverse mechanisms work synergistically to produce Gynostemma’s wide range of health benefits, from adaptogenic and anti-aging effects to cardiovascular protection and metabolic regulation.

The optimal dosage of Gynostemma pentaphyllum varies depending on the specific preparation, extraction method, and intended therapeutic purpose. In traditional use, Gynostemma is typically consumed as a tea, with 2-4 grams of dried leaves steeped in hot water daily. For modern standardized extracts, the dosage is typically based on the content of active compounds, particularly gypenosides. Standardized extracts containing 80-98% gypenosides are commonly used at dosages of 150-500 mg per day.

For general health maintenance and preventive purposes, lower dosages (150-300 mg of standardized extract) are typically sufficient. For specific therapeutic applications, higher dosages (300-500 mg of standardized extract) may be more appropriate. The onset of effects varies by condition, with some acute effects (such as improved energy) observable within hours, while other benefits (such as metabolic improvements or cardiovascular effects) may require consistent supplementation for 4-12 weeks.

The bioavailability of Gynostemma’s active compounds, particularly gypenosides, is relatively limited due to their large molecular size, high polarity, and susceptibility to degradation in the gastrointestinal tract. Pharmacokinetic studies in animal models suggest that the oral bioavailability of major gypenosides is approximately 2-10%, with significant variation between different gypenoside compounds. After oral administration, these compounds undergo extensive metabolism in the intestine and liver. Intestinal bacteria play a crucial role in the metabolism of gypenosides, cleaving the sugar moieties to release the aglycones, which may then be absorbed more readily.

Peak plasma concentrations of gypenosides typically occur 1-4 hours after oral administration, indicating relatively slow absorption. However, the majority of these compounds are not absorbed in their intact form. Despite this low systemic bioavailability, Gynostemma extracts demonstrate significant biological activity, suggesting several possible mechanisms: 1) The metabolites of gypenosides, rather than the parent compounds, may be responsible for many of the biological effects; 2) Local effects in the gastrointestinal tract may trigger systemic responses; 3) Small amounts of absorbed compounds may exert potent effects at their target tissues; 4) Cumulative effects with long-term administration may compensate for low single-dose bioavailability. The elimination half-life of absorbed gypenosides and their metabolites ranges from approximately 2-8 hours, indicating relatively rapid clearance from the bloodstream.

Excretion occurs primarily through the urine, with some elimination via the biliary route into feces.

Consumption with a small amount of fat may improve the absorption of certain lipophilic components, Taking Gynostemma with meals generally enhances absorption compared to taking it on an empty stomach, Micronization of Gynostemma powder increases the surface area available for absorption, Standardized extracts with higher concentrations of active compounds may overcome the low bioavailability through dose effect, Fermentation by probiotic bacteria can pre-metabolize gypenosides into more bioavailable forms, Liposomal formulations may enhance cellular uptake and improve systemic bioavailability, Combining with piperine (black pepper extract) may inhibit glucuronidation and increase bioavailability of certain compounds, Enteric-coated formulations can protect sensitive compounds from degradation in the stomach, Cyclodextrin complexation improves aqueous solubility while protecting compounds from degradation, Decoction with other herbs in traditional formulas may enhance extraction and absorption of active compounds

For optimal absorption and effectiveness, Gynostemma supplementation should follow specific timing considerations. Taking Gynostemma with meals, particularly those containing some fat, may enhance the absorption of certain lipophilic components, though the water-soluble glycosides that constitute many of the active compounds may not be significantly affected by food intake. Morning administration is often recommended for adaptogenic herbs like Gynostemma, aligning with the body’s natural cortisol rhythm. This timing may be particularly appropriate for Gynostemma’s energy-enhancing and stress-modulating effects.

However, for individuals who are sensitive to adaptogens or who experience improved sleep quality with Gynostemma, evening administration (at least 2-3 hours before bedtime) may be more beneficial. For metabolic benefits, particularly blood glucose regulation, taking Gynostemma approximately 15-30 minutes before meals may help optimize its effects on postprandial glucose levels. When using Gynostemma primarily for cardiovascular benefits, consistent daily timing is more important than specific time of day, as these effects accumulate with regular use over weeks to months. In traditional Chinese medicine, Gynostemma is often taken as a tea, which is typically consumed throughout the day.

For modern extract formulations, dividing the daily dose into two administrations (morning and evening) may provide more consistent levels of active compounds throughout the day, particularly for higher doses. For those using Gynostemma for immune support, some practitioners recommend cycling protocols (e.g., 3 weeks on, 1 week off) to prevent adaptation, though scientific evidence for this approach is limited. Consistency in daily administration is generally more important than precise timing for most of Gynostemma’s health benefits, as many effects build cumulatively with regular use over time.

• Mild gastrointestinal discomfort (occasional nausea, loose stools) – uncommon
• Increased bowel movements – uncommon
• Mild headache – rare
• Dizziness – rare
• Increased urination – uncommon

• Known allergy or hypersensitivity to Gynostemma or plants in the Cucurbitaceae family
• Caution advised in individuals with autoimmune disorders due to potential immune-modulating effects (theoretical concern, limited clinical evidence)
• Caution advised in individuals with bleeding disorders or those taking anticoagulant medications, due to potential mild antiplatelet effects
• Pregnancy and lactation (due to insufficient safety data, though no adverse effects have been reported)
• Scheduled surgery (discontinue at least 2 weeks before due to theoretical anticoagulant effects)

• Antidiabetic medications (potential additive effect on blood glucose lowering, generally beneficial but may require monitoring)
• Antihypertensive medications (potential additive effect, generally beneficial but may require monitoring)
• Anticoagulant and antiplatelet medications (theoretical risk of enhanced effect due to mild antiplatelet properties)
• Immunosuppressive medications (theoretical concern for immune modulation effects)
• Medications metabolized by cytochrome P450 enzymes (limited evidence for mild inhibition of certain CYP enzymes)

Gynostemma pentaphyllum has demonstrated an excellent safety profile in both preclinical toxicology studies and human clinical trials. Acute and chronic toxicity studies in animals have established a No Observed Adverse Effect Level (NOAEL) far exceeding typical human doses. In traditional use, Gynostemma tea has been consumed daily for extended periods without reported toxicity. In human clinical trials, doses up to 500 mg of standardized extract (80-98% gypenosides) daily have been used for periods of up to one year without significant adverse effects.

Most studies have used doses between 150-400 mg daily, which appear to be well-tolerated by the vast majority of participants. Based on the available evidence, a conservative upper limit for long-term daily consumption would be approximately 500-600 mg of standardized extract (80-98% gypenosides) for most healthy adults. Higher doses have not been well-studied for long-term safety. It’s worth noting that individual tolerance may vary, and some sensitive individuals may experience mild gastrointestinal discomfort at lower doses.

In such cases, starting with a lower dose (100-150 mg daily) and gradually increasing as tolerated is recommended. For children, pregnant women, and individuals with specific health conditions, particularly those with autoimmune disorders or bleeding tendencies, caution is advised due to limited safety data in these populations. As with any supplement, it’s advisable to start with lower doses and gradually increase if needed, monitoring for any adverse effects. Gynostemma is generally considered non-toxic and safe for long-term use at recommended doses, with no evidence of dependency, tolerance development, or withdrawal effects upon discontinuation.

In the United States, Gynostemma pentaphyllum is regulated as a dietary supplement under the Dietary Supplement Health and Education Act (DSHEA) of 1994. As a dietary supplement ingredient, it is not subject to the same pre-market approval process as pharmaceuticals. Manufacturers are responsible for ensuring their products are safe before marketing and that product labels are truthful and not misleading. Gynostemma does not have Generally Recognized as Safe (GRAS) status for use in conventional foods.

The FDA has not approved any specific health claims for Gynostemma supplements. Any claims made must be limited to general structure/function claims rather than disease treatment claims. For example, manufacturers can claim that Gynostemma ‘supports cardiovascular health’ but not that it ‘treats hypertension.’ The FDA has not established a specific upper limit for Gynostemma consumption. The FDA has not issued any significant safety warnings or recalls specifically related to Gynostemma, which reflects its generally good safety profile.

If Gynostemma were to be developed as a pharmaceutical agent for specific therapeutic applications, such as diabetes management, it would require formal FDA approval through the standard drug approval process, including clinical trials demonstrating safety and efficacy.

Eu: In the European Union, Gynostemma is not included in the list of approved novel foods or food supplements under Regulation (EC) No 258/97 or Regulation (EU) 2015/2283. This means that its regulatory status varies by member state, with some countries permitting its use in food supplements and others restricting it. The European Food Safety Authority (EFSA) has not evaluated or approved any health claims for Gynostemma. In some EU countries, Gynostemma may be available as a traditional herbal medicinal product under Directive 2004/24/EC, which provides a simplified registration procedure for traditional herbal medicinal products with a long history of use. However, specific approved products vary by country. The EU has not established a specific upper limit for Gynostemma consumption.

China: In China, Gynostemma (Jiaogulan) is officially recognized as a medicinal herb in the Chinese Pharmacopoeia. It is approved for use in various formulations and preparations for treating conditions such as hyperlipidemia, cardiovascular disorders, and as an adaptogenic tonic. The China Food and Drug Administration (now National Medical Products Administration) regulates Gynostemma-containing products as traditional Chinese medicines rather than as food supplements. In some regions of China, particularly in the south where it grows naturally, Gynostemma is also recognized as a food ingredient and is commonly consumed as a tea.

Japan: In Japan, Gynostemma (Amachazuru) has been approved as a ‘non-drug’ health food ingredient. Some Gynostemma products may be regulated as Foods for Specified Health Uses (FOSHU) or Foods with Function Claims (FFC) if scientific evidence supports their benefits. Manufacturers must notify the Consumer Affairs Agency before marketing such products. The Japanese Ministry of Health, Labour and Welfare has not established a specific upper limit for Gynostemma consumption.

Australia: The Therapeutic Goods Administration (TGA) in Australia regulates Gynostemma as a complementary medicine. Gynostemma-containing products may be listed on the Australian Register of Therapeutic Goods (ARTG) as AUST L products if they meet quality and safety standards. The TGA has not approved specific health claims for Gynostemma beyond general health maintenance claims. The TGA has not established a specific upper limit for Gynostemma consumption.

Canada: Health Canada regulates Gynostemma as a Natural Health Product (NHP). It may be issued a Natural Product Number (NPN) if the product meets the requirements for safety, efficacy, and quality. Health Canada has approved certain claims for Gynostemma, primarily related to its antioxidant properties and traditional use as an adaptogen. These approved claims are more specific than those allowed in the United States. Health Canada has not established a specific upper limit for Gynostemma consumption but generally recommends doses consistent with those used in approved clinical studies.

Low to Moderate

Gynostemma supplements are generally affordable compared to many other adaptogenic herbs and supplements. Dried Gynostemma leaves for tea typically cost $10-25 per pound, translating to approximately $0.10-0.30 per daily dose (2-4 grams). Tea bags containing Gynostemma range from $0.20-0.50 per bag, with one bag typically providing an effective daily dose. Standardized extracts in capsule or tablet form range from $0.20 to $0.80 per day for an effective dose (150-400 mg of extract standardized to 80-98% gypenosides).

Premium products from established brands, particularly those with higher standardization levels or additional testing for purity and potency, may cost $0.80-1.50 per day. The relatively low cost of Gynostemma is due to several factors: the plant grows quickly and abundantly in its native regions, it can be harvested multiple times per year, it requires minimal processing compared to many other herbs, and it has become widely cultivated in response to increasing demand. Additionally, the active compounds are present in relatively high concentrations in the leaves, requiring less raw material to produce effective extracts compared to herbs where the active compounds are found in roots or other parts that take longer to grow.

The value proposition of Gynostemma varies depending on the specific health application and individual factors. For metabolic health, particularly blood glucose regulation and lipid management, Gynostemma offers excellent value, with clinical studies showing significant improvements at doses of 300-500 mg of standardized extract daily. These effects are comparable to some pharmaceutical interventions but at a fraction of the cost and with fewer side effects. For cardiovascular health, Gynostemma provides good value, with studies demonstrating improvements in blood pressure, endothelial function, and lipid profiles at doses of 200-400 mg daily.

These benefits may be particularly valuable for individuals with mild to moderate cardiovascular risk factors who are seeking natural approaches. For adaptogenic support and stress management, Gynostemma offers very good value compared to other adaptogens. While herbs like Panax ginseng or Rhodiola may provide more immediate or potent effects for some individuals, they typically cost 3-5 times more than Gynostemma for an effective dose. Gynostemma’s gentle, balancing adaptogenic properties make it suitable for long-term use without the cost burden of more expensive adaptogens.

For immune support, Gynostemma provides moderate value, with preliminary evidence supporting its immunomodulatory effects. While more research is needed to fully establish its efficacy for specific immune-related conditions, its low cost makes it an accessible option for general immune support. When comparing different forms of Gynostemma, tea made from dried leaves offers the best cost efficiency but may provide less consistent dosing of active compounds compared to standardized extracts. Standardized extracts, while more expensive per dose, provide more reliable concentrations of gypenosides and may be more convenient for many users.

The long-term value of Gynostemma supplementation may be enhanced by its preventive effects on age-related conditions, potentially reducing future healthcare costs. However, this long-term economic benefit is difficult to quantify precisely. Overall, Gynostemma stands out as one of the more cost-effective adaptogenic herbs and metabolic support supplements available, providing significant health benefits at a relatively low cost compared to both pharmaceutical alternatives and other natural supplements with similar applications.

The shelf life of Gynostemma products varies significantly depending on the preparation method, storage conditions, and specific formulation. Dried Gynostemma leaves, when properly stored, typically maintain their quality for 2-3 years according to traditional practices. However, the active compounds, particularly gypenosides, may gradually degrade over time, with some studies suggesting a 10-15% reduction in gypenoside content per year under typical storage conditions. Modern standardized extracts in powder form generally have a shelf life of 2-3 years when stored properly in sealed containers.

Encapsulated or tablet forms of Gynostemma extracts typically maintain stability for 2-3 years, with manufacturers often providing a buffer period in their expiration dating to ensure potency throughout the labeled shelf life. Liquid extracts and tinctures generally have shorter shelf lives (1-2 years) due to increased exposure to oxygen and potential microbial growth, even with preservatives. Traditional tea preparations should be consumed within 1-2 days, even when refrigerated, as they lack preservatives and are highly susceptible to microbial contamination. Stability studies have shown that the gypenoside content may decrease more rapidly in environments with elevated temperature, humidity, or light exposure.

The flavonoid components of Gynostemma tend to be more stable than the gypenosides, maintaining their structural integrity for longer periods under proper storage conditions. Some research suggests that certain degradation products of gypenosides may retain biological activity, meaning that even with some chemical changes over time, the product may maintain some efficacy beyond the optimal shelf life.

Store Gynostemma products in their original containers with lids tightly closed to protect from moisture, oxygen exposure, and light. Keep in a cool, dry place away from direct sunlight and heat sources. The optimal temperature range is 59-77°F (15-25°C), with relative humidity below 60%. Avoid storing in bathrooms, kitchens, or other areas with fluctuating temperatures and high humidity.

Refrigeration is not necessary for dried herb or extract powders and may actually introduce moisture through condensation when the container is opened. However, liquid extracts may benefit from refrigeration after opening to slow microbial growth and enzymatic degradation. Protect from light by keeping in the original opaque container, as extended exposure to light can accelerate degradation of gypenosides and other active compounds. Minimize exposure to air by keeping the container closed when not in use and avoiding transferring to different containers unless necessary.

If transferring is required, use an airtight, opaque container. For bulk powders, use a clean, dry utensil to remove the product and reseal the container immediately after use to minimize exposure to air and moisture. Traditional herbalists recommend storing dried Gynostemma leaves in breathable paper bags or cotton pouches rather than plastic containers, which may trap moisture and promote mold growth. For Gynostemma tea bags or loose tea, store in an airtight container away from strong odors, as the leaves can absorb aromas from the environment.

If the product changes color significantly (becoming much darker), develops an unusual odor, or shows visible signs of mold or degradation, it should be discarded regardless of the expiration date.

Exposure to oxygen (oxidation is a primary degradation pathway for gypenosides), Exposure to light, particularly UV light, which accelerates oxidation reactions, High temperatures (above 86°F/30°C) significantly accelerate degradation, High humidity, which can promote hydrolysis of glycosidic bonds and microbial growth, Enzymatic degradation due to residual plant enzymes or microbial contamination, Extreme pH conditions (either highly acidic or alkaline), Presence of metal ions, particularly iron and copper, which catalyze oxidation reactions, Microbial contamination, particularly in liquid formulations or products with high moisture content, Freeze-thaw cycles, which can affect the physical stability of some formulations, Chemical interactions with other compounds in complex formulations, Prolonged exposure to air after opening the container, Improper drying of raw material, leading to residual moisture and accelerated degradation

Synthesis Methods

Natural Sources

Quality Considerations

Gynostemma pentaphyllum, commonly known as jiaogulan, has a rich history of traditional use in East Asia, particularly in the mountainous regions of southern China, where it earned the nickname ‘immortality herb’ due to its association with longevity. Despite its current popularity, Gynostemma has a relatively recent documented history compared to many other traditional Chinese herbs. The earliest written records of Gynostemma’s medicinal use date back to the Ming Dynasty (1368-1644 CE), where it was mentioned in local herbals from the mountainous regions of southern China, particularly Guangxi, Guizhou, and Sichuan provinces. In these early texts, it was primarily noted for its sweet taste and cooling properties, used to treat heatiness, inflammation, and as a general health tonic.

However, Gynostemma remained relatively obscure in the broader Chinese medical literature until the 20th century. The herb gained significant attention in the 1970s when Chinese researchers, conducting a nationwide census of longevity factors, discovered unusually high rates of centenarians in certain mountainous regions of southern China. Upon investigation, they found that regular consumption of a local tea made from Gynostemma leaves was a common dietary habit among these long-lived populations. This discovery prompted scientific interest in the plant and led to its more widespread recognition.

Interestingly, while Gynostemma was not prominently featured in classical Chinese medical texts, it has a longer history of use as a folk remedy among the minority ethnic groups of southern China, including the Miao, Yao, and Zhuang peoples. These communities traditionally used Gynostemma as a refreshing tea, an energy tonic, and a remedy for various ailments including cough, fatigue, and digestive disorders. In Japan, where the plant is known as ‘amachazuru,’ it has been used since at least the 17th century as a sweet tea and folk medicine for diabetes, cough, and as a general tonic. Similarly, in Korea, Thailand, and other parts of Southeast Asia, local populations have traditionally consumed Gynostemma as a tea and health-promoting herb.

The modern scientific understanding of Gynostemma began in the 1980s when Japanese researchers discovered that it contains compounds similar to the ginsenosides found in Panax ginseng, which they named gypenosides. This finding led to Gynostemma being marketed as ‘Southern Ginseng,’ despite not being botanically related to true ginseng. This discovery, combined with the longevity associations, catapulted Gynostemma from a regional folk remedy to international recognition. In the 1990s and 2000s, Gynostemma gained popularity in Western countries as research began to validate some of its traditional uses, particularly its adaptogenic, antioxidant, and metabolic benefits.

It has since become a common ingredient in adaptogenic formulas, metabolic support supplements, and longevity-focused products. Today, while Gynostemma is cultivated commercially in many countries, wild harvesting continues in its native regions, where local communities maintain their traditional relationships with this plant. The relatively recent emergence of Gynostemma on the global stage, compared to herbs with thousands of years of documented use, makes it somewhat unique in the world of traditional herbal medicine. It serves as a reminder that valuable medicinal plants may still exist in traditional knowledge systems that have not yet been fully documented or scientifically explored.

No comprehensive meta-analyses specifically focused on Gynostemma pentaphyllum supplementation are currently available. The limited number of high-quality clinical studies and their heterogeneity in terms of preparations, dosages, and outcome measures makes meta-analysis challenging., Li K, et al. Medicinal Value and Potential Therapeutic Mechanisms of Gynostemma pentaphyllum (Thunb.) Makino and Its Derivatives: An Overview. Current Topics in Medicinal Chemistry. 2019;19(32):2855-2867. This review analyzed the pharmacological effects, active compounds, and potential therapeutic mechanisms of Gynostemma, concluding that it shows promise for various health applications, particularly in metabolic disorders, cardiovascular diseases, and inflammatory conditions., Razmovski-Naumovski V, et al. Chemistry and Pharmacology of Gynostemma pentaphyllum. Phytochemistry Reviews. 2005;4:197-219. This comprehensive review examined the chemical constituents and pharmacological activities of Gynostemma, highlighting its potential for treating various conditions including hyperlipidemia, diabetes, and inflammatory diseases.

Evaluation of Gynostemma Extract for Metabolic Syndrome (hypothetical – no actual registered trial), Gynostemma Supplementation for Non-Alcoholic Fatty Liver Disease: A Phase II Trial (hypothetical – no actual registered trial), Effects of Standardized Gynostemma Extract on Cognitive Function in Elderly Adults (hypothetical – no actual registered trial), Gynostemma pentaphyllum for Exercise Performance Enhancement (hypothetical – no actual registered trial), Note: As of 2024, there are very few registered clinical trials specifically investigating Gynostemma for health purposes. Most research remains at the preclinical stage or involves small clinical studies rather than large-scale controlled trials.