The Early Show medical correspondent Dr. Emily Senay explains that PMS is the term used to describe a cluster of symptoms that affect some women before their period starts. Most women experience mild premenstrual mood changes or physical discomfort, but when those symptoms are severe enough to substantially interfere with everyday life and relationships, it's classified as premenstrual syndrome.
Symptoms could include depression, irritability, fatigue, abdominal cramping, breast tenderness and headaches.
It's estimated that between eight and 20 percent of women suffer from PMS.
Previous research has suggested calcium and vitamin D supplements may help reduce its severity.
And a study in this morning's Archives of Internal Medicine suggests that a diet rich in calcium and vitamin D, which helps the body absorb calcium, may lower the risk of developing PMS in the first place.
Researchers compared diet and supplement use in women aged 27 to 44 who developed PMS over a ten year span to that of women who didn't develop it. The researchers saw a 40 percent lower risk of developing PMS in women with high intakes of vitamin D and calcium.
In the study, the benefit was seen when women consumed the equivalent to about four servings per day of skim or low-fat milk, fortified orange juice or low-fat dairy foods such as yogurt, which added up to approximately 1200 milligrams of calcium and 400 International Units of vitamin D each day.
It isn't understood why calcium might help prevent PMS. One theory is that calcium affects the female hormone estrogen during the menstrual cycle.
The researchers say more research is needed to understand the role of calcium and vitamin D in treating and preventing PMS, including which foods are the most beneficial and whether or not calcium and vitamin D supplements are effective. Women should consult with a doctor to see whether they need more calcium for PMS.
The researchers say, since calcium is routinely prescribed early on for women to reduce bone loss in the prevention of osteoporosis, and may help prevent some cancers, that doctors may also now consider recommending calcium for PMS.