Magnesium shows up in almost every list of PMS remedies. Some small trials are encouraging, especially for bloating and mood, but the evidence is thinner than the internet suggests. Here's what the studies actually found, and how to use magnesium safely.
Written by Vita Globe Editorial Team | Reviewed against NIH guidance and peer-reviewed research
Does magnesium help with PMS?
It may help some symptoms, but the evidence is limited. The Office on Women's Health says magnesium may help relieve some PMS symptoms, including migraines[1]. In a small placebo-controlled trial, 200mg a day reduced fluid-retention symptoms like bloating and breast tenderness, but only in the second month[2]. Another small trial found magnesium plus vitamin B6 eased anxiety-related symptoms, while neither alone did[3].
Caveat: These trials were small and short. MedlinePlus notes most studies have found supplements including magnesium are not helpful for PMDD[4].
Sources: Office on Women's Health · Walker et al. 1998 · De Souza et al. 2000 · Verified 2026-09-28
IN THIS ARTICLE
Why is magnesium linked to PMS?
Magnesium is a mineral involved in hundreds of processes in the body, including muscle and nerve function[5]. That's part of why it's been studied for premenstrual symptoms such as cramps, bloating, headaches and mood changes.
The NIH Office of Dietary Supplements sets the recommended intake at 310mg a day for women 19 to 30 and 320mg for women 31 to 50[5]. Food sources include leafy greens, nuts, seeds, legumes and whole grains.
The Office on Women's Health includes magnesium in its list of vitamins and minerals that may help with PMS, noting it may relieve some symptoms, including migraines[1].
What do the studies show?
| Study | What they tested | What they found |
|---|---|---|
| Walker et al., 1998[2] | 200mg magnesium (as oxide) daily vs placebo for two cycles; 38 women; crossover design | No difference in month one. In month two, greater reduction in fluid-retention symptoms (weight gain, swelling, breast tenderness, bloating) than placebo |
| De Souza et al., 2000[3] | Magnesium 200mg, vitamin B6 50mg, both, or placebo for one cycle each; 44 women | Neither magnesium nor B6 alone had a significant effect; the combination modestly reduced anxiety-related symptoms |
| Facchinetti et al., 1991[6] | Oral magnesium for premenstrual mood changes | Reported improvement in premenstrual mood changes |
Taken together, the picture is promising but thin. The trials are small, short and older, and they used different forms and doses. Effects, when found, were modest and sometimes took more than one cycle to appear[2]. That's very different from the confident "magnesium fixes PMS" claims you see online.
Where magnesium probably won't help
If your premenstrual symptoms are severe, with deep depression, rage or anxiety that disrupts your life, that may be premenstrual dysphoric disorder (PMDD). MedlinePlus states that most studies have shown supplements such as vitamin B6, calcium and magnesium are not helpful for PMDD[4]. PMDD needs a healthcare provider; effective treatments include SSRIs and therapy[4]. If you ever have thoughts of harming yourself, call or text 988.
For more on the difference, read PMS vs. PMDD: What's the Difference?
How to take magnesium safely for PMS
- Food first. Leafy greens, pumpkin seeds, almonds, beans and whole grains all count toward your daily intake.
- Mind the upper limit. For adults and teens 9 and older, the upper limit for magnesium from supplements and medications is 350mg a day. That limit doesn't include magnesium from food[5]. The two trials in the table with stated doses used 200mg[2][3].
- Expect digestive effects at high doses. Too much supplemental magnesium often causes diarrhea, sometimes with nausea and cramping[5].
- Form matters for absorption. Forms that dissolve well, such as magnesium citrate, lactate, aspartate and chloride, are absorbed more completely than magnesium oxide or sulfate[5]. Our guide to magnesium glycinate vs. citrate covers the differences.
- Watch for interactions. Magnesium can interfere with some antibiotics and osteoporosis drugs (bisphosphonates), and certain diuretics and long-term acid reflux medicines can affect magnesium levels[5]. Ask your pharmacist about timing.
- Give it two cycles. In the fluid-retention trial, benefits showed up in the second month, not the first[2].
The honest summary
- Magnesium may ease some PMS symptoms, particularly bloating-type symptoms, and may work better paired with vitamin B6.
- The evidence comes from small, older trials, so expectations should be modest.
- Stay at or under 350mg a day from supplements, and don't rely on magnesium for PMDD.
Our option
Vita Globe Her PMS Gummies
Her PMS Gummies don't contain magnesium, so they can sit alongside a magnesium routine if your doctor agrees. They pair 20mg of vitamin B6, the nutrient that showed a combined effect with magnesium in one trial, with a 111mg PMS Support Blend of chasteberry, cranberry and dong quai per two-gummy serving. They're made to help ease occasional premenstrual moodiness and tension.* For adults only; not for use during pregnancy or nursing.
KEEP READING
Best Supplements for PMS · Vitamin B6 for PMS · Magnesium and Anxiety
Frequently asked questions
How much magnesium should I take for PMS?
Two of the trials used 200mg a day[2][3]. Don't exceed 350mg a day from supplements without medical advice[5].
Which type of magnesium is best for PMS?
No form has been proven best for PMS. Citrate and other soluble forms are absorbed better than oxide[5], though two of the PMS trials above used magnesium oxide[2][3].
Can magnesium help period cramps?
It's often suggested, but the evidence for cramps specifically is limited. NSAIDs and heat have stronger evidence; see PMS Cramps: What Actually Helps.
Can I take magnesium and vitamin B6 together?
Yes. In one small trial the combination helped anxiety-related PMS symptoms when neither did alone[3]. Keep total B6 under 100mg a day[7].
How long does magnesium take to help PMS?
In one trial, benefits for fluid retention appeared in the second cycle[2]. Give it at least two cycles.
Sources
- U.S. Department of Health and Human Services, Office on Women's Health. Premenstrual syndrome (PMS). womenshealth.gov. womenshealth.gov/menstrual-cycle/premenstrual-syndrome
- Walker AF, De Souza MC, Vickers MF, Abeyasekera S, Collins ML, Trinca LA. Magnesium supplementation alleviates premenstrual symptoms of fluid retention. J Womens Health. 1998;7(9):1157–1165. doi:10.1089/jwh.1998.7.1157
- De Souza MC, Walker AF, Robinson PA, Bolland K. A synergistic effect of a daily supplement for 1 month of 200 mg magnesium plus 50 mg vitamin B6 for the relief of anxiety-related premenstrual symptoms: a randomized, double-blind, crossover study. J Womens Health Gend Based Med. 2000;9(2):131–139. doi:10.1089/152460900318623
- National Library of Medicine. Premenstrual dysphoric disorder. MedlinePlus Medical Encyclopedia. Reviewed 2024. medlineplus.gov/ency/article/007193.htm
- National Institutes of Health, Office of Dietary Supplements. Magnesium — Fact Sheet for Health Professionals. NIH ODS. ods.od.nih.gov/factsheets/Magnesium-HealthProfessional
- Facchinetti F, Borella P, Sances G, Fioroni L, Nappi RE, Genazzani AR. Oral magnesium successfully relieves premenstrual mood changes. Obstet Gynecol. 1991. PMID: 2067759
- National Institutes of Health, Office of Dietary Supplements. Vitamin B6 — Fact Sheet for Health Professionals. NIH ODS. ods.od.nih.gov/factsheets/VitaminB6-HealthProfessional
About the Vita Globe Editorial Team
The Vita Globe Editorial Team researches and writes our wellness content, working from peer-reviewed research, systematic reviews and guidance from bodies such as the NIH and the FDA. We cite our sources inline and update articles when the evidence changes.
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. This article is for informational purposes only and is not a substitute for medical advice. Talk to your healthcare provider before starting any new supplement, particularly if you are pregnant, nursing, taking medication, or caring for a child.
