Calcium

Does calcium help with premenstrual syndrome?

Updated 4 Nov 2026

Short answer

It may, but most of the evidence has a risk of bias. In the largest trial of premenstrual symptoms, 466 women took 1,200 mg of calcium a day as carbonate or a placebo for 3 cycles. Symptoms fell by 48% with calcium and 30% with placebo.[1]

Smaller trials also found less low mood, water retention, pain and fatigue.[2][3] A pilot trial in 39 women found a much smaller effect of calcium than of fluoxetine, an antidepressant.[4] A 2025 review of 31 trials of nutrition and PMS found consistent benefits on mood symptoms with calcium, but only 1 of the 31 had a low risk of bias.[5]

For period pain, one trial in 85 students gave 1,000 mg a day from the middle of the cycle until the pain ended. Pain was 1.6 points lower than with placebo on a 10-point scale. Blood loss did not change.[6]

Sources (6)

  1. Calcium carbonate and the premenstrual syndrome: effects on premenstrual and menstrual symptoms. Premenstrual Syndrome Study Group. Thys-Jacobs S, Starkey P, Bernstein D, Tian J Am J Obstet Gynecol, 1998. PMID 9731851
  2. Calcium supplementation in premenstrual syndrome: a randomized crossover trial. Thys-Jacobs S, Ceccarelli S, Bierman A, Weisman H, Cohen MA, Alvir J J Gen Intern Med, 1989. PMID 2656936
  3. Effects of calcium supplement therapy in women with premenstrual syndrome. Ghanbari Z, Haghollahi F, Shariat M, Foroshani AR, Ashrafi M Taiwan J Obstet Gynecol, 2009. PMID 19574172
  4. A pilot study to compare fluoxetine, calcium, and placebo in the treatment of premenstrual syndrome. Yonkers KA, Pearlstein TB, Gotman N J Clin Psychopharmacol, 2013. PMID 23963058
  5. Effect of nutritional interventions on the psychological symptoms of premenstrual syndrome in women of reproductive age: a systematic review of randomized controlled trials. Robinson J, Ferreira A, Iacovou M, Kellow NJ Nutr Rev, 2025. PMID 38684926
  6. Effects of Calcium-Vitamin D and Calcium-Alone on Pain Intensity and Menstrual Blood Loss in Women with Primary Dysmenorrhea: A Randomized Controlled Trial. Zarei S, Mohammad-Alizadeh-Charandabi S, Mirghafourvand M, Javadzadeh Y, Effati-Daryani F Pain Med, 2017. PMID 27296057

More about calcium

What is calcium?Which foods contain calcium?Does calcium need vitamin D to work?How much calcium can the body absorb at one time?What is calcium used for?What happens if you do not get enough calcium?

For education; not medical advice. Talk to a doctor before you start, stop or change a supplement.