FactoWiki

Can magnesium help with PMS symptoms?

Last updated: August 2026 · Reviewed by the FactoWiki Editorial Team for clarity and source accuracy

There is reasonable evidence that it helps, particularly for mood symptoms, fluid retention and menstrual migraine. Trials generally used 200–360 mg daily, often taken through the second half of the cycle, and combining it with vitamin B6 appears to work better than magnesium alone.

Key takeaways

  • 200–360 mg daily is the trial range; effects build over 2–3 cycles.
  • Magnesium plus vitamin B6 outperformed magnesium alone in several studies.
  • Glycinate or citrate; avoid oxide, which is poorly absorbed and laxative.

What the trials found

Randomised trials of magnesium in PMS have shown reductions in mood symptoms, anxiety and fluid retention, with the clearest effects appearing by the second or third cycle rather than the first. Magnesium also has reasonable evidence for menstrual migraine prevention, where doses around 600 mg have been used. Effect sizes are moderate and the trials are mostly small, but the direction is fairly consistent.

The B6 combination

Several studies found that magnesium combined with vitamin B6 produced greater symptom reduction than either alone. B6 is involved in neurotransmitter synthesis, which is the proposed rationale. One important caution: B6 above roughly 100 mg daily long-term can cause peripheral neuropathy — tingling and numbness in hands and feet — which is why doses in PMS studies are usually kept to 50–80 mg.

Practical use

Some trials dose continuously, others only through the luteal phase — from ovulation to the period. Continuous dosing is simpler and has the advantage that magnesium status builds over time. Choose glycinate for tolerability or citrate if constipation is also a symptom. Give it three full cycles before judging.

Key ingredients to understand

The ingredients most relevant to this question, with what the evidence actually supports:

Frequently asked questions

What about calcium?

Calcium at around 1,200 mg daily has some of the better PMS trial evidence, particularly for mood and physical symptoms. It is worth considering alongside magnesium.

Will magnesium help period pain specifically?

Some evidence, though less than for mood and fluid retention. Its muscle-relaxant effect on the uterus is the proposed mechanism.

When is PMS actually PMDD?

When mood symptoms are severe enough to disrupt work or relationships. PMDD is a recognised diagnosis with specific treatments and warrants a doctor's assessment rather than self-management.

Related on FactoWiki

This article is general information, not medical advice. FactoWiki may earn a commission from links on product review pages (never on comparisons). Always check with a qualified healthcare professional about your own situation.