TORBANGUN RESEARCH
Elk Haven Herbals • Research reference • Updated September 2026
About This Research
Torbangun (Coleus amboinicus, also known as Plectranthus amboinicus) has a long history of use as a postpartum food and traditional lactation aid in Indonesia. Modern research has examined torbangun in breastfeeding mothers, animal models, and human mammary-cell models.
We keep this page as a running record of the published research rather than relying on a single study or a single proposed mechanism. The studies have used different preparations including whole leaves, tea, soup, brownies, snack bars, extracts and supplemental foods and have measured different outcomes such as breast-milk volume, infant weight, prolactin and lactation-related gene expression (the receptors responsible for binding to the hormones that result in more milk production). We’re only just beginning to understand exactly how these work in the body. There’s a more detailed video here of me drawing how this works if you’re more of a visual learner.
The biggest study by far was a 2026 systematic review that identified 11 recent human studies and found that torbangun was associated with increased breast-milk volume overall, while results for infant weight were more variable. The review also noted substantial differences between studies and limited reporting of adverse events.
What the Research Has Investigated
Breast-milk production and milk volume
Infant weight and other indicators of breastfeeding success
Prolactin and other lactation-related hormones
Prolactin-receptor expression in mammary tissue
STAT5A and β-casein expression in human mammary cells (genes that control mammary tissue function).
Traditional postpartum use
Comparisons with other lactation herbs and polyherbal products
Safety and biological activity
Breast-Milk Production & Milk Volume
2006 — Human breastfeeding study — A controlled study found that torbangun supplementation was associated with a 65% increase in milk volume from day 14 to day 28, without a deterioration in measured milk nutritional quality.
2018 — Torbangun leaf extract — A postpartum study reported increased breast-milk production after torbangun extract and also reported an increase in maternal prolactin.
2019 — Torbangun leaves — A quasi-experimental study of 32 mothers reported significantly greater breast-milk production in the torbangun group.
2022 — Torbangun leaf drink — A controlled study reported greater infant-weight gain, used as an indicator of milk production, among mothers consuming torbangun leaf drink.
2022 — Torbangun leaves in postpartum mothers — A human study of torbangun leaf consumption reported a significant improvement in breast-milk production compared with the control group.
Recent human studies summarized in 2026 review — Studies using torbangun tea, extract, soup, brownies, snack bars and supplemental foods generally reported increased milk-volume or milk-production measures, although two cohort studies did not find significant differences in breastfeeding frequency, duration or infant anthropometric status.
Infant Weight & Breastfeeding Outcomes
Infant weight outcomes — 2026 systematic review — Across four eligible studies, the pooled analysis found greater infant weight gain with torbangun, but the result was highly heterogeneous and became uncertain when torbangun was compared specifically with no intervention.
Torbangun snack bar — 2026 review — A placebo-controlled study found greater increases in infant weight, urination, defecation and sleep duration in the torbangun snack-bar group, along with greater breast-milk volume.
Torbangun tea — 2023 — A study of torbangun tea reported greater infant weight gain after seven days and interpreted the result as evidence of increased milk production.
Torbangun leaves — 2019 — A study of torbangun soup reported a significant effect on breast-milk production based on infant-weight outcomes.
Prolactin & Lactation Hormones
2018 — Prolactin and milk production — A human study reported that 14 days of torbangun leaf tea increased both prolactin levels and breast-milk production.
2019 — Prolactin receptor in mammary tissue — In lactating rats, an ethyl-acetate fraction of torbangun increased milk production and increased expression of the prolactin-receptor gene without significantly increasing serum prolactin.
Animal prolactin research — A rat study found that torbangun leaf powder affected prolactin levels, although changes in litter weight were not consistently different between treatment groups.
2022 polyherbal human study — A randomized study of a mixture containing torbangun, katuk and papaya found increased milk volume and infant weight in both treatment groups, while prolactin decreased in both groups.
How Torbangun May Work: PRLR, STAT5A & Milk-Protein Signaling
2019 — Prolactin-receptor signaling — Torbangun's lactation effect in rats was associated with increased mammary-gland prolactin-receptor gene expression, suggesting that the plant may influence how mammary tissue responds to prolactin rather than simply increasing circulating prolactin.
2024 — Human mammary cells: PRLR, STAT5A and β-casein — In human MCF-12A mammary epithelial cells, the water fraction of torbangun increased expression of PRLR, glucocorticoid receptor, STAT5A and β-casein, while the ethyl-acetate fraction increased glucocorticoid receptor, STAT5A and β-casein.
2017 — Lactogenic activity in rats — An ethyl-acetate fraction of torbangun increased estimated milk production in lactating rats and was associated with identified flavonoid-related compounds.
2024 — Human-cell lactation pathway research — The human-cell findings provide preliminary evidence that torbangun can affect several genes involved in mammary development and milk-protein production, including the prolactin-signaling pathway.
Traditional Use & Historical Evidence
Traditional use in North Sumatra — An ethnographic study documented the long-standing Bataknese practice of giving torbangun to women for about one month after childbirth, with the plant traditionally viewed as nourishing and supportive of milk production and postpartum recovery.
Traditional food and lactation research — The early human research grew directly from the documented Bataknese tradition of preparing torbangun as a postpartum food.
Comparisons With Other Lactation Herbs
2006 — Torbangun compared with fenugreek — In the early controlled human study, milk volume increased 65% with torbangun from day 14 to day 28, compared with 20% with fenugreek and 10% with the comparison product.
2024 — Torbangun-containing polyherbal formula — A randomized trial compared a mixture of katuk, torbangun and papaya with a katuk-only commercial galactagogue and found similar increases in milk volume and infant weight in both groups.
2024 — Polyherbal safety and laboratory measures — In the polyherbal trial, average liver and kidney laboratory values remained within normal ranges, while a small percentage of mothers experienced elevated liver enzymes or nausea; no infant side effects were reported.
Safety & Research Limitations
Preclinical safety evidence — Animal research summarized in the 2026 systematic review has not identified major adverse changes in hematological, biochemical or histological measures, but human safety data remain limited.
2026 systematic review — safety — The most recent systematic review found that adverse events were rarely reported across the human studies and called for better-designed studies with standardized preparations and systematic safety reporting.
2024 human mammary-cell study — Torbangun extract and fractions showed IC50 values above 20 μg/mL in the MCF-12A cell model, providing preliminary information about cellular tolerance but not clinical safety.
2026 Systematic Review & Meta-Analysis
Read the full 2026 systematic review → The review identified 11 eligible human studies. Across the studies, torbangun was administered as tea, extract, soup, brownies, snack bars or supplemental food. The pooled analysis found a significant increase in breast-milk volume, while infant-weight results were more heterogeneous. The authors emphasized differences in dosage forms, intervention durations, study designs and limited adverse-event reporting.
What the Research Suggests So Far
The most consistent human finding is an increase in breast-milk volume or other measures of milk production.
Some studies report increased prolactin, but increased prolactin is not seen consistently across the literature.
Animal research suggests that torbangun may increase prolactin-receptor expression in mammary tissue, potentially changing the mammary gland's response to prolactin.
A 2024 human mammary-cell study found changes in PRLR, STAT5A and β-casein expression, providing additional preliminary evidence for a lactation-related cellular mechanism.
Evidence for improved infant weight gain is promising in some studies but less consistent than the evidence for milk-volume outcomes.
The studies use different preparations and doses, so results from one preparation should not automatically be assumed to apply to another.
The human evidence is still dominated by relatively small studies, and better randomized trials with standardized preparations and more complete safety reporting are needed.
Why We Keep Updating This Page
Torbangun research is still developing. New studies can add evidence about effectiveness, mechanism, preparation, dosage and safety. Rather than treating the existing evidence as the final word, Elk Haven Herbals maintains this page as a living reference to the published literature. New relevant studies can be added as they appear.
Research note: This page summarizes published research and is not medical advice. The available studies vary substantially in design, preparation, dose and outcome measurement.