Chrysin
TL;DR
A flavonoid from passionflower and honeycomb marketed as an aromatase inhibitor for testosterone support, but human evidence shows it is essentially ineffective orally due to near-zero bioavailability.
Ideal For
- Nobody, based on current human evidence
Avoid If
- You are spending money on it for testosterone support
- You take medications metabolized by UGT enzymes (theoretical interaction)
Frequently Asked Questions
Overview
Chrysin (5,7-dihydroxyflavone) became popular in bodybuilding circles after in-vitro studies showed it inhibits aromatase, the enzyme that converts testosterone to estrogen. The problem is pharmacokinetics: chrysin undergoes rapid intestinal and hepatic conjugation (glucuronidation and sulfation), and human studies consistently show oral chrysin does not raise testosterone, lower estrogen, or alter body composition. It remains a cautionary example of a compound with exciting cell-culture data that fails completely in humans at practical doses. Honest verdict: skip it for hormone support.
How It Works
- Inhibits aromatase in vitro at micromolar concentrations
- Orally it is rapidly glucuronidated and sulfated, leaving negligible free chrysin in plasma
- Human trials show no effect on testosterone, estrogen, or body composition
- Any purported benefit in products likely comes from other ingredients
Health Concerns Addressed
No linked health concerns yet.
Supporting Research8 studies
Effects of androstenedione-herbal supplementation on serum sex hormone concentrations in 30- to 59-year-old men
Brown GA, Vukovich MD, Martini ER +2 more
Serum concentrations of total testosterone and PSA were unchanged by supplementation. DION increased (p < 0.05) serum androstenedione (342%), free testosterone (38%), dihydrotestosterone (71%), and estradiol (103%) concentrations.
Disposition and metabolism of the flavonoid chrysin in normal volunteers
Walle T, Otake Y, Brubaker JA +2 more
Oral chrysin was extensively conjugated and systemic bioavailability was extremely low.
Developing nutritional component chrysin as a therapeutic agent: Bioavailability and pharmacokinetics consideration, and ADME mechanisms
Gao S, Siddiqui N, Etim I +2 more
Although chrysin's biological activities have been demonstrated and the mechanism of actions has been determined using in vitro and in vivo models, results from the current clinical studies were largely negative.
Effects of chrysin on urinary testosterone levels in human males
Gambelunghe C, Rossi R, Sommavilla M +5 more
Oral chrysin did not produce meaningful changes in urinary testosterone levels in men.
Evaluation of the mutagenic activity of chrysin, a flavonoid inhibitor of the aromatization process
Oliveira GA, Ferraz ER, Souza AO +2 more
The MN test showed that from 1 to 15 microM of this flavonoid mutagenic activity was noted in HepG2 cells.
A Comprehensive Review on Chrysin: Emphasis on Molecular Targets, Pharmacological Actions and Bio-pharmaceutical Aspects
Garg A, Chaturvedi S
However, its therapeutic applications have been limited due to its poor oral bioavailability. The major reason for its poor bioavailability is its extensive first-pass metabolism.
Chrysin: Sources, beneficial pharmacological activities, and molecular mechanism of action
Mani R, Natesan V
In general, chrysin exhibits many biological activities and pharmacological effects, including antioxidant, anti-inflammatory, anticancer, and antiviral activities.
Impact of chrysin on the molecular mechanisms underlying diabetic complications
Farkhondeh T, Samarghandian S, Roshanravan B
The findings indicate that chrysin has protective effects against diabetes outcomes by modulating oxidative stress, inflammation, and apoptosis in animal models.
Safety Information
Potential Side Effects
Well tolerated, unsurprising given how little is absorbed; no consistent adverse effects.
Drug Interactions
- substrates of UGT-mediated metabolism (theoretical)
Pregnancy & Breastfeeding
Pregnancy: insufficient_data
Breastfeeding: insufficient_data
Dosage Guidelines
Dosage Used in Studies
Consult healthcare provider
Forms Compared
Food & Timing
Not applicable
Medical Disclaimer
The information provided on this website is for educational and informational purposes only and is not intended as a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition or before starting any supplement regimen.
Individual results may vary. The statements on this website have not been evaluated by the Food and Drug Administration. Products and information are not intended to diagnose, treat, cure, or prevent any disease.