About Vitex (Chaste Tree Berry)
Chaste tree berry (Vitex agnus-castus) acts on pituitary dopamine D2 receptors to lower prolactin and modulate the luteal phase. It is one of the better-evidenced women's-health botanicals: multiple RCTs and a 2017 systematic review/meta-analysis (Am J Obstet Gynecol) support symptom relief in premenstrual syndrome and PMDD, anchored by the Schellenberg 2001 BMJ RCT (Ze 440, 20 mg/day, 52% improvement vs 24% placebo) and a dose-finding study identifying ~20 mg as effective. Caveats: most positive trials used the standardized Ze 440 extract and several were manufacturer-funded, and reviewers note heterogeneity and risk of bias. Most US retail products are whole-berry or non-standardized extracts at much higher mg, which lack dose-matched evidence. Not an essential nutrient.
What Vitex (Chaste Tree Berry) supports
- May reduce PMS/PMDD symptoms (standardized extract, RCT evidence)
- Lowers prolactin via dopaminergic activity, modulating the cycle
How much Vitex (Chaste Tree Berry) to take
The RDA prevents deficiency. The effective range is what clinical trials used to actually move the outcome.
Effective
20–40
mg
Dose is standardization-dependent. Validated standardized extract (Ze 440) works at 20 mg/day; German Commission E lists 30–40 mg. Whole-berry/crude products use 160–400 mg+ but lack agnuside standardization and matched trial evidence. Agnuside/casticin content is the real potency marker, not raw mg.
Clinical evidence
Moderate clinical evidence. Multiple RCTs and a 2017 meta-analysis support PMS benefit (esp. standardized Ze 440 at 20 mg); reviewers flag heterogeneity and industry funding
Reference