Women who consume more calcium from their diets are less likely to suffer severe PMS.¹ A large double-blind trial found that women who took 1,200 mg per day of calcium for three menstrual cycles had a 48% reduction in PMS symptoms, compared to a 30% reduction in the placebo group.² Other double-blind trials have shown that supplementing 1,000 mg of calcium per day relieves premenstrual symptoms.^3,4

Many,^8,9,10,11,12 though not all,¹³ clinical trials show that taking 50–400 mg of vitamin B6 per day for several months help relieve symptoms of PMS. A composite analysis of the best designed controlled trials shows that vitamin B6 is more than twice as likely to reduce symptoms of PMS as is placebo.¹⁴ Many doctors suggest 100–400 mg per day for at least three months. However, intakes greater than 200 mg per day can cause side effects and should never be taken without the supervision of a healthcare professional.Vitamin B6 has also been reported to relieve cyclic breast pain.¹⁵

Vitex has been shown to help re-establish normal balance of estrogen and progesterone during the menstrual cycle. Vitex also blocks prolactin secretion in women with excessive levels of this hormone; excessive levels of prolactin can lead to breast tenderness and failure to ovulate. A double-blind trial has confirmed that vitex reduces mildly elevated levels of prolactin before a woman’s period.¹⁶ Studies have shown that using vitex once in the morning over a period of several months helps normalize hormone balance and thus alleviate the symptoms of PMS.¹⁷ Preliminary and double-blind research has found that vitex relieves PMS symptoms. The amount in most of these trials was 20 mg per day of a concentrated vitex extract for three menstrual cycles experience a significant reduction in symptoms of PMS.^18,19,20

Vitex has been shown to be as effective as 200 mg vitamin B6 in a double-blind trial of women with PMS.²¹Two surveys examined 1,542 women with PMS who had taken a German liquid extract of vitex for their PMS symptoms for as long as 16 years.²² With an average intake of 42 drops per day, 92% of the women surveyed reported the effectiveness of vitex as “very good,”“good,” or “satisfactory.”

Some healthcare practitioners recommend 40 drops of a liquid, concentrated vitex extract or one capsule of the equivalent dried, powdered extract once per day in the morning with some liquid. Vitex should be taken for at least four cycles to determine efficacy.

Women with PMS have been shown to have impaired conversion of linoleic acid (an essential fatty acid) to gamma linolenic acid (GLA).²³ Because a deficiency of GLA might, in theory, be a factor in PMS and because evening primrose oil (EPO) contains significant amounts of GLA, researchers have studied EPO as a potential way to reduce symptoms of PMS. In several double-blind trials, EPO was found to be beneficial,^24,25,26,27 whereas in other trials it was no more effective than placebo.^28,29

Despite these conflicting results, some doctors consider EPO to be worth a try; the amount usually recommended is 3–4 grams per day. EPO may work best when used over several menstrual cycles and may be more helpful in women with PMS who also experience breast tenderness or fibrocystic breast disease.³⁰

Women with PMS have been reported to be at increased risk of magnesium deficiency.^32,33 Supplementing with magnesium may help reduce symptoms.^34,35 In one double-blind trial using only 200 mg per day for two months, a significant reduction was reported for several symptoms related to PMS (fluid retention, weight gain, swelling of extremities, breast tenderness, and abdominal bloating).³⁶ Magnesium has also been reported to be effective in reducing the symptoms of menstrual migraine headaches.³⁷ While the ideal amount of magnesium has yet to be determined, some doctors recommend 400 mg per day.³⁸ Effects of magnesium may begin to appear after two to three months.

Some of the nutrients helpful for premenstrual syndrome appear together in multivitamin-mineral supplements. One double-blind trial used a multivitamin-mineral supplement containing vitamin B6 (600 mg per day), magnesium (500 mg per day), vitamin E (200 IU per day), vitamin A (25,000 IU per day), B-complex vitamins, and various other vitamins and minerals.³⁹ This supplement was found to relieve each of four different categories of PMS symptoms. Related results have been reported in other clinical trials.^40,41

A preliminary, uncontrolled trial found that women with severe PMS who took potassium supplements had complete resolution of PMS symptoms within four menstrual cycles.⁴² Most participants took 400 mg of potassium per day as potassium gluconate plus 200 mg of potassium per day as potassium chloride for the first two cycles, then switched to solely the gluconate form (600 mg potassium per day) for the remainder of the year-long trial. Without exception, all of the women found their symptoms (i.e., bloating, fatigue, irritability, etc.) decreasing gradually over three cycles and disappearing completely by the fourth cycle. Controlled trials are needed to confirm these preliminary observations.

Although women with PMS do not appear to be deficient in vitamin E,⁴⁴ a double-blind trial reported that 300 IU of vitamin E per day may decrease symptoms of PMS.⁴⁵

Black cohosh is approved in Germany for use in women with PMS.⁴⁷ This approval appears to be based on historical use as there are no modern clinical trials to support the use of black cohosh for PMS.

In Traditional Chinese Medicine, dong quai is rarely used alone and is typically used in combination with herbs such as peony (Paeonia officinalis) and osha (Ligusticum porteri) for menopausal symptoms as well as for menstrual cramps.⁴⁸ However, no clinical trials have been completed to determine the effectiveness of dong quai for PMS.

A double-blind trial has shown that standardized Ginkgo biloba extract, when taken daily from day 16 of one menstrual cycle to day 5 of the next menstrual cycle, alleviates congestive and psychological symptoms of PMS better than placebo.⁴⁹ The trial used 80 mg of a ginkgo extract two times per day.

In Traditional Chinese Medicine, dong quai is rarely used alone and is typically used in combination with herbs such as peony (Paeonia officinalis) and osha (Ligusticum porteri) for menopausal symptoms as well as for menstrual cramps.⁵⁰ However, no clinical trials have been completed to determine the effectiveness of dong quai for PMS.

Most well-controlled trials have not found vaginally applied natural progesterone to be effective against the symptoms of premenstrual syndrome.⁵¹ Only anecdotal reports have claimed that orally or rectally administered progesterone may be effective.⁵² Progesterone is a hormone, and as such, there are concerns about its inappropriate use. A physician should be consulted before using this or other hormones. Few side effects have been associated with use of topical progesterone creams, but skin reactions may occur. The effect of natural progesterone on breast cancer risk remains unclear; some research suggests the possibility of increased risk, whereas other research points to a possible reduction in risk.

In a double-blind trial, supplementing with soy protein (providing 68 mg of isoflavones per day) for two menstrual cycles was significantly more effective than a placebo at relieving premenstrual swelling and cramping.⁵³ The placebo used in this study was cow's milk protein. Some doctors believe that cow's milk, because of its estrogen content, can worsen premenstrual symptoms. If that is the case, then the beneficial effect of soy protein may have been overestimated in this study.

Very high amounts of vitamin A—100,000 IU per day or more—have reduced symptoms of PMS,^55,56 but such an amount can cause serious side effects with long-term use. Women who are or who could become pregnant should not supplement with more than 10,000 IU (3,000 mcg) per day of vitamin A. Other people should not take more than 25,000 IU per day without the supervision of their doctor. As yet, no trials have explored the effects of these safer amounts of vitamin A in women suffering from PMS.

Many years ago, research linked B vitamin deficiencies to PMS in preliminary research.^57,58 Based on that early work, some doctors recommend B-complex vitamins for women with PMS.⁵⁹

Based on anecdotal evidence, yarrow tea has been used by European doctors when the main symptom of PMS is spastic pain.⁶⁰ Combine 2–3 teaspoons of yarrow flowers with one cup of hot water, then cover and steep for 15 minutes. Drink three to five cups per day beginning two days before PMS symptoms usually commence. In addition, 1–3 cups of the tea added to hot or cold water can be used as a sitz bath.