More Iron, Less PMS

Premenstrual syndrome likelihood decreases with greater iron consumption

(RxWiki News) Iron can reduce fatigue and prevent anemia. Now, women may have another reason to add more of the mineral to their diet: to ease PMS symptoms.

New research showed that women who consumed a diet rich in iron were up to 40 percent less likely to have premenstrual syndrome (PMS) compared to women who consumed less iron.

Knowing which micro-minerals can help with the mood swings and bloating that come with PMS could provide some comfort to women before and during their periods. 

"Talk to your doctor about iron supplements."

PMS is marked by physical and emotional symptoms linked with the luteal phase of a woman's menstrual cycle, or the week going into her period.

Elizabeth Bertone-Johnson, PhD, associate professor in the School of Public Health and Health Sciences at the University of Massachusetts Amherst, and colleagues measured the mineral intake of about 3,000 women who were part of the Nurses' Health Study II.

The participants were surveyed about their food consumption three times over a 10-year period.

At the end of the 10 years, 1,057 women with an average age of 40 years were diagnosed with PMS. Another 1,986 women were PMS-free.

Results showed that women who consumed the most non-heme iron - a type of iron found mainly in plant foods and dietary supplements - were 30 to 40 percent less likely to have PMS symptoms compared to women who consumed the least.

Consuming more than 20 milligrams of iron per day improved PMS symptoms. That amount is higher than the recommended dietary allowance, according to researchers, for women between 20 and 40 years of age.

"Although one serving of iron-fortified cereal provides this level of intake (100 percent of the recommended dietary allowance), it may otherwise be difficult to achieve this level from food sources alone," researchers wrote in their report.

"Additional studies of iron and PMS are needed to confirm this finding and determine whether the benefits of iron supplementation outweigh the potential harmful effects," they wrote.

Results also showed that other minerals affected PMS symptoms. Taking zinc supplements, or consuming about 25 milligrams per day, cut the risk of PMS symptoms by more than 20 percent.

Women who consumed the most potassium (recommended daily allowance of 4,700 milligrams per day), on the other hand, were about one and a half times more likely to have PMS symptoms than women who consumed the least.

Sodium, manganese and magnesium were not linked to PMS risk.

The authors noted that they did not look at daily symptom records to identify women with PMS.

Furthermore, their findings focused on women diagnosed with PMS after 25 years of age. As such, the findings may not be applicable to adolescent girls or young adults with PMS.

The study was published February 26 in the American Journal of Epidemiology. The authors did not declare any conflicts of interest.

The study was supported by GlaxoSmithKline Consumer Healthcare, Rexall/Cellasene and a Public Health Services grant from the National Cancer Institute.

Review Date: 
February 26, 2013