---
title: Does evening primrose oil (gamma-linolenic acid) reduce PMS symptoms?
description: Yes. Women taking about 180 mg per day of gamma-linolenic acid showed greater improvements in PMS symptom duration, severity, and irritability compared to wom
url: https://niyora.com/research/papers/efficacy-of-gamma-linolenic-acid-for-treatment-of-premenstrual-syndrome-as-2005/
---

- [Niyora](https://niyora.com/)
- [Research](https://niyora.com/research/)
- [Library](https://niyora.com/research/library/)
- Does evening primrose oil (gamma-linolenic acid) reduce PMS symptoms?

Randomised trial, 2005

# Does evening primrose oil (gamma-linolenic acid) reduce PMS symptoms?

Yes. Women taking about 180 mg per day of gamma-linolenic acid showed greater improvements in PMS symptom duration, severity, and irritability compared to women taking placebo.

 Moderate study design

28 women diagnosed with PMS

## What they did

28 women diagnosed with PMS took either vegetable oil containing about 180 mg per day of gamma-linolenic acid (GLA) or placebo for three luteal phases. Researchers measured PMS symptoms daily and checked GLA levels in blood before and after treatment.

## What they found

Before treatment, women with PMS had significantly lower levels of DGLA (a related compound) in their blood compared to women without PMS. After GLA treatment, women taking GLA had significantly higher levels of both GLA and DGLA in their blood compared to the placebo group and compared to their own baseline. Women taking GLA showed significantly greater improvement in the overall duration and severity of PMS symptoms and in irritability compared to those taking placebo.

## What it means for you

GLA (from evening primrose oil) may help reduce how long PMS symptoms last and how severe they are, with possible effects on irritability. The study suggests GLA may work by restoring lower-than-normal blood levels in women with PMS. However, this was a small study (28 women) and needs confirmation in larger trials.

180 mg

Dose of GLA per day

28

Women studied

3

Treatment cycles

## About the study

Original title Efficacy of .GAMMA.-linolenic Acid for Treatment of Premenstrual Syndrome, as Assessed by a Prospective Daily Rating System Authors Shinji Watanabe, 櫻田 美穂, Hiroaki TSUJI et al. Journal Journal of Oleo Science Year 2005 Study design Randomised trial What was tested Vegetable oil containing gamma-linolenic acid for three menstrual cycles Open access Yes Read the paper [doi.org/10.5650/jos.54.217](https://doi.org/10.5650/jos.54.217)

## Topics

[Premenstrual syndrome (PMS)](https://niyora.com/research/topics/condition-pms/)[Evening primrose oil](https://niyora.com/research/topics/treatment-evening-primrose/)

Research tells you what helps on average. Niyora helps on the day it hits.

Calm down, see it another way, and decide what to say, with a PMS and PMDD app built by a doctor.

## Related studies

Systematic review, 2009

Which herbs, vitamins and minerals help treat PMS?

Systematic review, 2007

What treatments work for premenstrual syndrome?

Study, 2002

Which PMS treatments have good scientific evidence?

Randomised trial, 2000

Which dietary supplements help PMS?

Study, 2024

Does a combination of evening primrose oil, tocotrienol, and vitamin B6 reduce premenstrual symptoms?

Randomised trial, 2024

Does a herbal soft gel capsule with three oils reduce PMS symptoms?

Ask AI about this page

Copy prompt

ChatGPT

↗

Claude

↗

Perplexity

↗

Google AI Mode

↗

Grok

↗