We don't know exactly how diet impacts PMS. But some research has shown that increasing complex carbohydrates before menstruation helps increase the levels of the neurotransmitter serotonin, a deficiency of which has been linked to PMS-related depression. Although complex carbohydrates (such as those found in whole grains and vegetables) are good to eat during PMS, simple carbohydrates (such as those found in sugary snacks and white bread) can actually increase water retention, irritability and other PMS symptoms.
Experts also recommend that menstruating women take vitamins, especially a daily multivitamin containing folic acid (which is essential for the growth of the fetus should conception occur) and a calcium supplement with vitamin D (which helps bones stay strong and may also help alleviate PMS symptoms). Some researchers think Vitamin B6 may ease symptoms, particularly depression, but its effectiveness has not been clinically proven, and very high doses (500 mg to 2,000 mg daily) can cause nerve damage.
Dieticians sometimes recommend that women who are experiencing PMS eat several small meals throughout the day rather than three big meals. Eating a lot of food at once can cause blood sugar to swing up and down, which some people believe might exacerbate PMS symptoms.
Experts say that certain foods should be avoided:
Women should also avoid nicotine because, in addition to its other health risks, it can affect PMS symptoms much like caffeine.
A 2005 study found that women who ate a diet rich in vitamin D and calcium had less of a risk of developing PMS than women who didn't eat these nutrients. To see a benefit, the women in the study had to eat at least 1,200 milligrams of calcium and 400 IU of vitamin D each day. Researchers don't know exactly why vitamin D and calcium warded off PMS symptoms, but they say it may have something to do with calcium's effect on the hormone estrogen during the menstrual cycle.