Benefits
Blood sugar: studied in people with type 2 diabetes
One small randomized trial gave gynostemma tea to adults already diagnosed with type 2 diabetes and reported lower fasting glucose and better HbA1c than placebo (Huyen 2010, PMID 20213586). It was a single small trial at one center, in patients rather than healthy people, so it does not show what the herb does for someone with normal blood sugar. Gynostemma is not a treatment for diabetes and should not replace prescribed medication.
AMPK activation mechanism
Laboratory and animal studies suggest gypenosides switch on AMPK, an enzyme that helps cells sense and manage energy. This is a proposed explanation rather than a proven one: only one small human trial cited on this page measured AMPK, in muscle after exercise, and a shared laboratory pathway does not make an herb comparable to a prescription medicine.
Insulin sensitivity: one small trial, in patients
The same small tea trial in adults with type 2 diabetes reported better insulin sensitivity alongside the glucose results (PMID 20213586). No trial cited here was run in people with metabolic syndrome, and no cited study tested whether gynostemma adds anything on top of diet and exercise.
Blood pressure: unchanged versus placebo in the diabetes tea trial
In the 12-week trial of gynostemma tea in 24 adults with type 2 diabetes, blood pressure did not differ between the tea and placebo groups, so there is no support here for a blood pressure claim. If you take blood pressure medication, talk to your doctor before adding any new supplement.
Cholesterol and triglycerides: preliminary review evidence
A 2022 systematic review pooled randomized trials of gynostemma in people with dyslipidemia and found signs of improvement in some cholesterol and triglyceride measures (Dai 2022, PMID 36091752). The reviewers themselves flagged small sample sizes, short study lengths and a high risk of bias, so this is preliminary. Nothing in that review shows an effect on heart attacks, strokes or any other health outcome.
VO2max and exercise fatigue: one 12-week trial of a gypenoside L extract
In a double blind trial, 100 healthy Korean adults aged 19 to 60 took a Gynostemma extract containing gypenoside L or placebo for 12 weeks. VO2max and oxygen pulse were higher than in the placebo group, and perceived exertion and a fatigue score were lower. The published summary does not give the dose, and one author works at a company research center.
Anxiety in stressed adults: one placebo-controlled trial
A randomized, double blind, placebo controlled study in adults under chronic psychological stress reported lower anxiety scores with a standardized gynostemma leaf extract (Choi 2019, PMID 30599899). It is a single, short, industry linked trial, and it does not make gynostemma a treatment for an anxiety disorder.
Body weight and body fat: one 12-week actiponin trial in obese adults
80 Korean adults with obesity but no diagnosed disease took 450 mg a day of actiponin, a branded heat-processed gynostemma extract, or placebo for 12 weeks. Body weight, body fat mass, percent body fat, BMI and total abdominal fat area fell more than with placebo. A single trial of one branded extract, so it says nothing about gynostemma tea or other extracts. A later correction fixed table footnotes and says the data stand.
Endurance cycling: one 4-week crossover trial in 16 untrained young men
In a double blind, placebo controlled crossover trial, 16 healthy untrained young men took 450 mg a day of a branded Gynostemma leaf extract (about 2.25 g of dried leaf) for 4 weeks. They finished a 20 km cycling time trial about 4% faster than on placebo, but time to exhaustion did not change. A company, Gencor Pacific, funded the research and the product, and the sample was small.
Mechanism of action
AMPK Thr172 phosphorylation activation
In laboratory studies, gypenosides switch on AMPK, a cell enzyme that responds to low energy. This is mostly preclinical work. In one small human cycling trial cited here, muscle AMPK Thr172 phosphorylation rose after exercise with gynostemma, and rose earlier than with placebo.
Hypolipidemic SREBP / HMGCR / PCSK9 pathways
Cell and animal studies point to effects on several genes and enzymes that control how the body makes and clears cholesterol and triglycerides. These are laboratory findings offered as a possible explanation for the lipid results, not measurements made in the human trials.
Insulin sensitivity + glucose uptake
Improved insulin sensitivity and greater glucose uptake by cells are the proposed explanation for the blood sugar findings. The supporting human data are one small randomized trial of gynostemma tea in adults with type 2 diabetes (PMID 20213586), not mechanism measurements in people.
Muscle energy use (proposed, not tested here)
In the small 4-week cycling trial, muscle biopsies showed higher mitochondrial oxygen flux with gynostemma than with placebo. That is a single industry funded study, so how gynostemma affects muscle energy use is still unsettled.
Fat tissue signaling (proposed)
Effects on fat tissue signaling have been proposed to explain the body composition findings. The cited weight trial measured body weight and fat, not the underlying signaling, so this remains a hypothesis.
Anxiolytic via HPA axis
How gynostemma might affect anxiety is not established. The one cited trial in chronically stressed adults reported the outcome, not the mechanism, and words like adaptogen describe a traditional idea rather than a measured process.
Clinical trials
Clinical evidence on Gynostemma pentaphyllum (Jiaogulan / Southern Ginseng) for the indications and outcomes described.
Clinical population described in trial publication.
A small randomized trial run by Hanoi Medical University with the Karolinska Institutet in 24 adults with newly diagnosed type 2 diabetes who were not yet on medication. Participants drank 6 g a day of gynostemma tea (3 g twice daily, 30 minutes before meals) for about 12 weeks and had lower fasting plasma glucose and improved HbA1c compared with placebo (PMID 20213586). With 24 people at a single center it is a preliminary result in patients, not proof of an effect in healthy people.
Randomized, double blind, placebo controlled trial in healthy adults with chronic psychological stress.
Clinical population described in trial publication.
A randomized, double blind, placebo controlled trial of a standardized gynostemma leaf extract in healthy adults with chronic psychological stress reported lower anxiety scores than placebo (Phytomedicine, 2019). It is single, short and industry linked, and it did not test exercise performance.
Clinical evidence on Gynostemma pentaphyllum (Jiaogulan / Southern Ginseng) for the indications and outcomes described.
Clinical population described in trial publication.
A randomized, double blind, placebo controlled trial of actiponin, a specific branded heat processed gynostemma extract, in adults with obesity. Over 12 weeks body weight, body fat mass, percent body fat, BMI and total abdominal fat area fell more in the extract group than with placebo (PMID 23804546). It is one small, short, industry linked trial of one branded extract, so it does not show that gynostemma tea or other extracts do the same thing.