Summary
Studies have shown that certain vitamins of the vitamin B complex are important in the nerve-related chemical synthesis that are associated with premenstrual syndrome  or PMS. This study attempted to see if vitamin B, in diet and in the form of vitamin supplements, plays a role in PMS development. The results revealed that taking vitamin B supplements does not predispose to developing PMS. On the other hand, two of the B vitamins, thiamine and riboflavin, taken from dietary sources, reduce the risk of PMS by 35 percent if consumed for two to four years.

Introduction
Premenstrual syndrome affects nearly 15 percent of the women in the reproductive age group. It manifests with several symptoms that can be both physical and psychological. The actual pathology of this condition is still not known. At present, there are several hormonal treatments for PMS, but these drugs sometimes cause serious side effects. Therefore, finding alternative strategies to prevent PMS is important. Studies have shown that several of the B vitamins are responsible for the formation of brain chemicals that may have a role in PMS. However, there have been no studies to show whether regular consumption of B vitamins will prevent PMS. This study was conducted to assess the role of each of the B vitamins in the prevention of PMS.

Methodology
* For the study, a large population of nurses, including 116,678 women from the United States, was studied for a 10-year period beginning in 1989.
* At the beginning of the study, the women were aged between 25 and 42 years and did not have PMS.
* All the women were asked to answer questionnaires related to food and vitamin supplements in the years 1991, 1995 and 1999. After the 10-year study period, there were 1,057 women who had developed PMS and 1,968 women without PMS. The women without PMS were compared with those with PMS.

Results/Key findings
* The results showed that women who ate riboflavin and thiamine in their diet regularly for two to four years had reduced risk of developing PMS.
* The rest of the B vitamins in diet, including niacin, vitamin B 6, folate and vitamin B 12, did not affect the risk of PMS.
* Conversely, the results showed that women who took vitamin B supplements had a higher risk of PMS in general, than those who did not take such supplements.

Next steps/Shortcomings
The authors agree that although the results showed decreased risk of PMS on consumption of thiamine and riboflavin in diet, the risk increases if one takes vitamin B supplements. This contradictory finding is unexplained. The authors also write that earlier studies have shown beneficial effect of vitamin B6 in the treatment of PMS; whereas, this study failed to demonstrate any such beneficial effect. They suggest that this could be due to the lower amount of the vitamin B6 consumed in diet, as compared to that consumed by participants in the earlier study. Further stuies are warranted to understand the exact role of B vitamins in the prevention of PMS, state the authors.

Conclusion
The results of this study suggest a “possible benefit of high intakes of riboflavin and thiamine from food sources on the incidence of PMS.” Because this study is the first of its kind, the authors suggest that more research needs to be conducted, to understand the effects of each of the B vitamins on the pathology and prevention of PMS, as well as their effectiveness of treatment. Since PMS affects many women and is quite debilitating, a possible method for prevention would be welcome. Another important finding of this study is that only dietary B vitamins appear to prevent PMS; whereas, its supplements do more harm than good. This calls for recommending improved thiamine- and riboflavin-rich diet to women who are susceptible to developing PMS.

For More Information:
Dietary Vitamin B Intake and Incident Premenstrual Syndrome
American Journal of Clinical Nutrition, February 2011
By Patricia O. Chocano-Bedoya; JoAnn E Manson; University of Massachusetts, Amherst and Harvard Medical School, Boston, Massachusetts

*FYI Living Lab Reports Are Summaries of the Original Research.