some benefit with magnesium, St. John’s wort, and vitamin E. There was no benefit in their review of evening primrose oil. A meta-analysis reviewing the data on supplements for dysmenorrheal concluded there was effectiveness for magnesium, vitamin B1, and vitamin B6, and data for magnesium was promising (23).
Calcium Calcium, 900 to 1,200 mg per day in divided doses, has at least some effect on the symptoms of PMS, premenstrual dysphoric disorder, and dysmenorrheal, specifically negative affect (mood swings, depression, tension, anxiety, crying spells), water retention (edema of extremities, breast tenderness, abdominal bloating, headache, fatigue), food cravings (changes in appetite, cravings for sweet or salt), and pain (lower abdominal cramping, generalized aches and pains, low backache) (22). One of the largest studies to date examined the effect of calcium, 1,200 mg per day, and reported a 50% decrease in PMS symptoms (24). In addition, the Women’s Health Study showed that higher intakes of calcium and vitamin D may be associated with a lower risk of developing breast cancer in premenopausal women, particularly with more aggressive breast tumors (25).
Vitamin B6 Vitamin B6 binds to estrogen and progesterone receptors and was the subject of most of the randomized controlled trials regarding CAM and PMS. Evidence suggests some benefit over placebo for the symptoms of mastalgia, swollen breasts, pain, and depression. Another review of randomized controlled trials indicated that although most of these trials demonstrated some benefit, definite clinical recommendations could not be made (26). While most controlled studies on vitamin B6 in the treatment of PMS had limited numbers of patients, which makes the evidence of positive effects fairly weak, this is a benign therapy in doses of 100 mg or less and is reasonable to support. Vitamin B6 for the treatment of dysmenorrheal was more effective at reducing pain than both placebo and a combination of magnesium plus vitamin B6 (23). It is important to note that peripheral neuropathies can be seen in doses of 200 mg per day or higher, as well as interaction with other medications, specifically anti-Parkinson’s disease drugs.
Magnesium Magnesium has less evidence for efficacy in treating the symptoms of PMS than calcium, although low magnesium levels were reported in women who have PMS. Whereas the evidence is less strong, several studies show a significant decrease in PMS symptoms (27,28). In the three randomized controlled trials, only the study using magnesium pyrrolidone carboxylic acid showed significant effect. One with no effect was limited by only 1 month of supplementation. In research on its effectiveness for dysmenorrheal, magnesium was more effective than placebo for pain relief, and the need for additional medication was less. There was no significant difference in the number of adverse effects experienced (23).
Although more studies are needed to clearly determine effectiveness and which formulation is most efficacious, use of magnesium is reasonable to support clinically and counteracts the constipating effects of calcium. Magnesium can be taken in 200 to 400 mg per day divided doses, either cyclically during the luteal phase or continuously.