Damiana
Best-in-class: Damiana
A traditional aphrodisiac herb for libido, mood and mild relaxation, used by both men and women.
Damiana quick facts
| Suggested dose | As directed (tea, tincture or capsules). |
| How often | Daily, or as needed |
| Who it's for | Libido and mood support (men and women). |
Traditional use is extensive and the human trials are essentially absent, which is the honest position. Where it appears in positive trials it is always within a combination product, so attribution is impossible. Mild and low-risk. The anxiolytic component may be doing more of the work than the aphrodisiac framing suggests, since anxiety suppresses desire.
How Damiana actually works
Turnera diffusa contains flavonoids with weak aromatase inhibition and apigenin, plus compounds with mild anxiolytic activity. The traditional aphrodisiac use has animal data behind it showing increased sexual behavior in rodents; the human mechanism is not established.
Where to get Damiana
Find Damiana on iHerb →The evidence for Damiana
Graded by what exists behind each claim.
✅ Clinically validated
- Traditional/animal evidence for aphrodisiac and mood effects; human trials are sparse.
- Mild anxiolytic and mood-lifting activity reported.
📊 Correlative data
- Traditional Mexican and Central American use as an aphrodisiac and mood tonic, documented since Spanish colonial records. Persistent traditional use, no meaningful modern trial or cohort data.
🧪 Theoretical / extrapolated benefits
- A gentle libido-and-mood herb; evidence is mostly traditional.
How to read these tiers: they say how much human evidence exists, not how well something works — and ✗ flags harm, never a disappointing trial. How the evidence tiers work →
What Damiana actually does
Turnera diffusa is a small aromatic shrub of Mexico and Central America, and unlike most traditional aphrodisiacs its constituents have been catalogued properly: the genus review lists 135 Turnera species and identifies the compound classes that carry the pharmacology Szewczyk 2014. Three of those classes matter here, and each maps onto a different named target.
Target one is aromatase, and damiana is a better inhibitor of it than most things sold as one. The crude damiana extract inhibited aromatase with an IC50 of 63.1 µg/mL, and the constituents responsible were identified: pinocembrin at 10.8 µM and acacetin at 18.7 µM Zhao 2008. Those are flavonoids, and CYP19A1 is being competitively occupied by a planar molecule that resembles a steroid A-ring — the same chemistry that made chrysin famous, in a plant nobody markets as an aromatase inhibitor. The same paper measured a second activity in the same extract, with apigenin 7-glucoside, Z-echinacin and pinocembrin returning EC50 values of 10, 20 and 67 µM Zhao 2008, which is why the honest reading of damiana's hormonal profile is ‘does two opposite things in a dish’ rather than ‘raises testosterone’.
Target two is nitric oxide synthase, and the rat experiment was designed to prove it rather than to suggest it. Turnera diffusa improved sexual behavior in male rats at 10 to 40 mg/kg, with sildenafil citrate at 10 mg/kg as a positive control and L-NAME at 12.5 mg/kg — a nitric oxide synthase inhibitor — used to block the effect Estrada-Reyes 2013. That design is the finding. Sildenafil works downstream of nitric oxide by blocking phosphodiesterase-5 and preserving cyclic GMP; L-NAME works upstream by stopping NO being made at all. An effect that survives beside sildenafil and disappears under L-NAME is an NO-dependent effect, and that is a far more specific claim than ‘traditional aphrodisiac’.
Target three is not a target, it is a hazard, and it has a name. Tetraphyllin B, a cyanogenic glycoside, was isolated from Turnera diffusa and reported in 1981 Spencer 1981. Cyanogenic glycosides are inert until a beta-glucosidase — the plant's own on maceration, or the gut microbiota's after swallowing — hydrolyzes the sugar and releases hydrogen cyanide. That is the molecular explanation for the historical reports of headache and, at extreme intakes, convulsions, and it is considerably more useful than repeating the anecdote.
Cell, rodent, human — and where it stops
Dish first, with the numbers. Aromatase inhibition at 10.8 and 18.7 µM for the isolated flavonoids, 63.1 µg/mL for the crude extract Zhao 2008. Micromolar in a well is the normal flavonoid result and it is the normal flavonoid problem: plant flavonoids are glucuronidated in the intestinal wall, and plasma concentrations after ordinary oral doses land in the nanomolar range rather than the micromolar one. Nobody has ever measured plasma pinocembrin or acacetin after a cup of damiana tea, so the size of that gap for this particular plant is unknown — but the direction is not in doubt.
Rodent, and for once the dose scales sensibly. Rats responded at 10–40 mg/kg Estrada-Reyes 2013. Converting a rat dose to a human one by the standard body-surface-area factor of about 6.2 puts 40 mg/kg in a rat at roughly 6.5 mg/kg in a person — about 450 mg for a 70 kg adult. That is squarely inside what a damiana capsule or a strong infusion delivers, which is unusual: most botanical rodent studies convert to doses nobody could swallow. The obstacle here is not the dose.
Human, and this is where the page turns. There is no randomized trial of damiana on its own in humans Szewczyk 2014. The randomized human evidence people cite is a multi-ingredient product: 77 women, 34 assigned to ArginMax and 43 to placebo, with 73.5% of the treated group reporting improvement against 37.2% on placebo, p < 0.01 Ito 2001. That is a real randomized result with a real separation from placebo, and it is worth taking seriously.
Then read what was in the capsule. The product's published formula pairs L-arginine with ginseng, ginkgo, damiana and a vitamin-mineral base — the trial report names the product, not a single herb. L-arginine is the direct substrate of nitric oxide synthase — the enzyme the rat study identified as damiana's own pathway Estrada-Reyes 2013. So the single trial supporting damiana in humans contains, as its headline ingredient, the substrate for the mechanism damiana is proposed to use. If the effect is real and the pathway is NO, arginine is the parsimonious explanation and damiana is along for the ride. Nobody has run the arm that would separate them.
So the specific obstacle is not species and not dose. It is attribution. Every other page in this cohort fails at the gut wall or at the trial length. Damiana fails at the question “which ingredient did that?”, and it fails there in the only human trial it has.
Damiana — which form, and does it matter
Preparation changes the product more here than in almost anything else on this shelf, because part of the chemistry is volatile. Damiana leaf carries an essential oil, and a hot infusion extracts volatile terpenes that a swallowed capsule of dried leaf largely does not, while an ethanolic tincture pulls the flavonoids — pinocembrin, acacetin, apigenin glycosides — far more efficiently than water does Zhao 2008 Szewczyk 2014. Tea, tincture and capsule are three different preparations of one leaf, and no trial has compared them.
There is essentially no standardization in commerce, and the reason is chronological. A validated quantitative UHPLC-DAD assay for damiana's constituents was only published in 2019 Willer 2019. A reference method for checking what is in a damiana product has existed for about six years, which is why almost no bottle states a marker compound and why comparing two brands is guesswork.
The genus itself is a substitution risk. There are 135 Turnera species Szewczyk 2014, and material sold as damiana has historically included more than one of them. Since the aromatase-active constituents were identified in T. diffusa specifically Zhao 2008, a label that names only “damiana” without the binomial has not told you which plant you bought.
And the traditional preparation contains a drug nobody counts. Damiana's classic form in its home region is a liqueur. Ethanol is anxiolytic, disinhibiting and vasodilating in its own right, at a dose far more reliable than anything the leaf delivers. Any self-assessment done on a damiana liqueur is an assessment of a cocktail, and the herb is the smaller variable in it.
What would have to be true, and how you would know it was not
1. estradiol-sensitive and total-testosterone, and the prediction is flat. Damiana inhibits aromatase in a dish at 10.8 and 18.7 µM Zhao 2008 — genuinely, measurably, in the same range as the flavonoids sold explicitly for it. Draw sensitive estradiol and total testosterone before and at eight weeks and predict no change, because a micromolar in-vitro potency in a glucuronidated plant flavonoid does not reach a human enzyme. If either number moved, it would be the first hormonal effect ever measured for this plant in a person.
2. The prediction that separates damiana from its own trial. The one randomized human result belongs to a product whose lead ingredient is the substrate of the pathway Ito 2001 Estrada-Reyes 2013. So predict this: damiana alone will not reproduce it. The design that would settle it is three arms — damiana alone, L-arginine alone, both — scored on the same instrument, and it has never been run. Anybody who repeats the 73.5%-versus-37.2% figure as a damiana result should be asked which arm it came from.
3. Endothelial function, which is where an NO mechanism would actually show up. Flow-mediated dilation is the standard non-invasive measure of nitric-oxide-dependent vasodilation. Predict FMD unchanged on damiana alone at eight weeks; predict it responds to L-arginine. That is a mechanism-level discrimination between the two ingredients that does not need a hormone panel or a sex-life questionnaire, and it is the cleanest test on this page.
4. Glucose, because the traditional caution points there. Predict fasting glucose and hba1c unchanged over twelve weeks in someone without diabetes. Predict any measurable effect only where a glucose-lowering drug is already working — which makes this a prediction about an interaction rather than about an effect, and the reason to test is additive hypoglycemia rather than benefit.
5. Liver enzymes, named because of the company it keeps. Damiana is almost always sold inside a libido blend. Predict alt and ast unchanged on damiana alone; draw them anyway, because if they move the cause will be something else in the capsule and you will want the baseline that lets you say so.
What nobody has tested yet
Nobody has given damiana alone to a human in a randomized trial. That is the sentence this whole page is built around Szewczyk 2014. Traditional use going back to colonial records, a defensible rodent mechanism Estrada-Reyes 2013, identified active constituents Zhao 2008 — and not one controlled study of the leaf by itself in people.
Nobody has measured its flavonoids in human plasma. The aromatase claim rests entirely on well concentrations Zhao 2008. One pharmacokinetic study — pinocembrin and acacetin by mass spectrometry after a defined dose of a defined extract — would tell you in an afternoon whether the hormonal argument is worth having at all, and it has never been done for this plant.
Nobody has surveyed tetraphyllin B in commercial product. The cyanogenic glycoside was identified in 1981 Spencer 1981 and a validated quantitative assay for damiana constituents has existed since 2019 Willer 2019. Putting the two together across twenty retail products is a straightforward analytical study, it would tell consumers how much headroom the “only at very high doses” caveat actually has, and it has not been published.
And nobody has taken the alcohol out. The traditional preparation is a liqueur and the modern one is a capsule; whether they do the same thing has never been compared, and the ingredient most likely to be responsible for the traditional reputation is the one that never appears in a supplement.
Damiana — its own safety story, not its category's
The cyanogenic glycoside is this plant's own risk story, and it deserves the mechanism rather than the folklore. Tetraphyllin B is present in Turnera diffusa Spencer 1981. Cyanogenic glycosides are harmless until hydrolyzed, and then they release hydrogen cyanide; the historical damiana reports of headache and, at extreme intakes, convulsions are exactly what that chemistry would produce. Two things follow. At culinary and ordinary supplemental amounts this has not been a practical problem in centuries of use. And nobody has ever quantified how much tetraphyllin B is in a retail damiana product Willer 2019, so “only at very high doses” is a statement whose margin nobody has measured.
The hormone-sensitive-cancer caution belongs here for a specific reason rather than as boilerplate. The same extract that inhibits aromatase at 63.1 µg/mL was also active in a second assay in the same paper, with apigenin 7-glucoside, Z-echinacin and pinocembrin returning EC50 values of 10, 20 and 67 µM Zhao 2008. A plant with two separate measured activities on the steroid-hormone machinery of a cell is not one to assume neutral in breast, ovarian or uterine cancer, or alongside tamoxifen or an aromatase inhibitor — even though poor absorption probably means nothing reaches the tissue. ‘Probably nothing’ is the right expectation and the wrong basis for a decision in that setting.
Blood glucose, and the drug it stacks with. Damiana is traditionally reported to lower blood sugar. On metformin, a sulfonylurea, a GLP-1 agonist or insulin, that is additive rather than parallel, and the hypoglycemia belongs to the combination rather than to either part. Anyone in that position should be testing more often for the first fortnight rather than assuming a leaf is too mild to count.
And the practical risk is the blend, not the herb. Damiana is rarely sold alone. The bottle it arrives in usually also contains yohimbe, maca, tribulus, a stimulant or all four, and the adverse effects reported by people taking “damiana” are usually adverse effects of something else in the capsule. Read the full ingredient panel before attributing anything — good or bad — to this plant. In pregnancy and breastfeeding there is no data at all, and a cyanogenic glycoside of unmeasured concentration Spencer 1981 is the wrong category of unknown to accept then.
Sources read for this page
- Zhao J, et al. Anti-aromatase activity of the constituents from damiana (Turnera diffusa). Journal of Ethnopharmacology 2008 · PMID 18948180
- Estrada-Reyes R, et al. Pro-sexual effects of Turnera diffusa Wild (Turneraceae) in male rats involves the nitric oxide pathway. Journal of Ethnopharmacology 2013 · PMID 23298455
- Ito TY, et al. A double-blind placebo-controlled study of ArginMax, a nutritional supplement for enhancement of female sexual function. Journal of Sex & Marital Therapy 2001 · PMID 11554217
- Spencer KC, et al. Tetraphyllin B from Turnera diffusa. Planta Medica 1981 · PMID 17402031
- Willer J, et al. Cytotoxic Properties of Damiana (Turnera diffusa) Extracts and Constituents and A Validated Quantitative UHPLC-DAD Assay. Molecules 2019 · PMID 30823394
- Szewczyk K, et al. Ethnobotany, phytochemistry, and bioactivity of the genus Turnera (Passifloraceae) with a focus on damiana - Turnera diffusa. Journal of Ethnopharmacology 2014 · PMID 24468305
How you would know if it worked
There is no blood test for this one. That is not a criticism — it is a fact about the effect, and it changes how you should judge it.
- What to watch: Two things, scored separately, because it is sold for both: desire, counted as days in a fortnight you actually wanted sex, and evening tension, rated 0 to 10 at the same hour each night. Human evidence here is thin enough that your own log is the only data there is, which is an argument for keeping it strictly rather than loosely.
- How long before it means anything: Four weeks. It is usually taken as a tea or a tincture, so the dose varies between servings far more than a capsule would — fix the preparation and the amount before you start, or you are testing a slightly different product every evening.
- What will fool you: It is almost always sold inside a blend, and the blend usually contains something faster and better evidenced. Read the label: if there is maca, ginseng or a stimulant in there, damiana is not the ingredient you are scoring. Alcohol is the other one — the traditional preparation is a liqueur, and a relaxing drink relaxes people on its own.
Run it one variable at a time. Starting three things in one week means a result you cannot attribute, which is the same as no result.
Damiana — safety & side effects
- Well tolerated at culinary and supplemental doses. Very high doses have produced headache and, historically, convulsions — the reports are old and involve extreme intakes.
- May lower blood sugar; watch for additive effects with diabetes medication.
The same on every page it applies to. Read it here; it is not repeated research.
- Not established as safe in pregnancy or breastfeeding — not because harm is documented, but because these are the two populations systematically excluded from the trials. Absence of data is not reassurance.
Not medical advice. If you take prescription medication or have a diagnosed condition, check this against it with a pharmacist or doctor — pharmacists are underused and free.
- When to take it, and what to take it with
- Which form actually absorbs
- Who it's worth it for
- Best-in-class brand pick
- Coach Cam's stacks and notes
- Fasted or with food, and when in the day
- Morning or night, and why that window
- Around training, or deliberately away from it
- What it must not share a window with
Everything above is free and stays free. Skool is where it becomes a plan — Damiana in an order, with the rest of what you're running.
Unlock in Skool — $10/mo →Bloodwork to run alongside Damiana
Baseline first, then again at 8–12 weeks.
| Marker | What it’s watching for |
|---|---|
| TSH (Thyroid-Stimulating Hormone) | Thyroid sits upstream of most things labeled 'hormonal' |
| Free T4 (Thyroxine) | Distinguishes a real thyroid problem from a borderline TSH |
| Total Testosterone | The baseline, if any of this is aimed at androgens |
| Vitamin D (25-Hydroxy) | Behaves like a hormone and is commonly low |
The Basics — Start Here panel covers these in one order — 4 markers, $32.40 with the discount applied.
Check results you already have → · All 103 markers A–Z
Damiana — frequently asked questions
What is Damiana?
A traditional aphrodisiac herb for libido, mood and mild relaxation, used by both men and women.
What is the suggested dose of Damiana?
As directed (tea, tincture or capsules). This is a general reference for education only — statements have not been evaluated by the FDA and this is not medical advice.
Where can I find Damiana dosing and the full breakdown?
The suggested dose and the full evidence — clinical, correlative and theoretical — are on this page. What's inside Skool is when to take it, which form actually absorbs, the brand worth buying and Coach Cam's stacks.
Where can I buy Damiana?
Coach Cam sources Damiana from vetted, top-rated brands on iHerb — use the buy link on this page.
What Damiana is used for
Damiana appears under 1 goal in the goal router.
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Where this goes next
The pages here are the frameworks. The protocols — the dosing, the order to correct things in, the week-by-week schedule and what to retest — are inside Skool.