A Calcium Link to PMS Relief?
Elevated, daily calcium doses, or more than double current dietary levels, may relieve some of the “psychological and physical discomforts†of women suffering from premenstrual syndrome or PMS, according to federal researchers.
The findings, released by the U.S. Department of Agriculture last week, could have “important implications†for as many as 50% of women in their child-bearing years, according to James G. Penland, Ph.D., a psychologist with the USDA’s Agriculture Research Service in Grand Folks, N.D.
“Women--in a 5 1/2-month controlled study--reported significantly fewer problems with mood swings common to premenstrual syndrome, with concentration and with behavioral changes when they got 1,300 milligrams of calcium per day instead of 600 milligrams. They also reported fewer aches and pains during menstruation on the high calcium intake,†according to the report.
The study’s results are a potential breakthrough because current treatment for PMS relies primarily on over-the-counter drugs such as acetaminophen, ibuprofen and aspirin or higher dose prescription medicine. Most treatments deal with the symptoms of PMS and not with the causes.
“PMS occurs in the last seven to 10 days of the menstrual cycle. . . . While premenstrual syndrome remains a mysterious malady, there is growing recognition that it is a true physical syndrome,†according to a recent U.S. Food and Drug Administration report released independent of the USDA study.
The FDA outlined four major categories of PMS symptoms. The first group includes breast tenderness, swelling, weight gain and bloating. The second involves emotional changes such as depression, forgetfulness, crying, insomnia and confusion. Another grouping includes headaches, food cravings (especially sweets), increased appetite, fatigue and dizziness. The fourth symptom category groups together anxiety, nervous tension, mood swings and irritability.
The USDA’s recommended dietary allowance of calcium for women between the ages of 25 and menopause is 800 milligrams a day. For women between the ages of 18 and 24 the recommendation is for 1,200 milligrams daily. However, the USDA estimates that American women, on average, get only about 600 milligrams of calcium each day.
Penland, who co-authored the study with USDA research chemist Phyllis E. Johnson, said that the report has undergone peer review by four government scientists and one private-sector physician. The study is currently being submitted for publication to a scientific journal and may appear later this year or in early 1992. Nevertheless, USDA frequently releases research results before they are published in medical or academic journals.
“If (the results) are accurate then, yes, this is significant. It is a brand new concept and big news,†said Connie M. Weaver, Ph.D., chair of Purdue University’s Food and Nutrition Department and a nationally recognized expert on calcium issues. “I have confidence in the investigators but I can’t comment further because I haven’t seen the paper.â€
Less enthusiastic was Wayne Bidlack, Ph.D., acting chair of the Pharmacology and Nutrition Department at the USC Medical School.
“I am a skeptic,†he said. “There is always a possibility that some nutritional factor could effect PMS. But there have been a lot of red herrings in the past. At times, magnesium and zinc have been promoted as providing relief. . . . However, that one nutrient could effect the symptoms is possible, but not likely.â€
Bidlack is also concerned that the participants may have been deceived by a placebo effect.
“Anyone experiencing a change in diet and given a supplement tends to believe they are getting relief and they may, indeed, be getting relief. But the real question is whether this is maintained or does it dissipate over time,†Bidlack said.
Participants for the study, who ranged in age from 20 to 35, were recruited nationally and lived at the USDA’s Grand Forks nutrition center for 165 days, during which time their diets were strictly supervised by the researchers. All their activities were monitored as well.
Although 14 subjects were initially enrolled, only 10 finished the project. Penland said that the small number of participants does not negate the study because the results were judged “statistically significant†according to established scientific standards.
“I think the data is valid and is interesting and has a lot of important implications,†Penland said. “If calcium is consumed at levels of approximately the recommended dietary allowance then that could reduce the severity of PMS symptoms that so many women experience.â€
Penland said that a follow-up study to confirm his results is currently under way.
“Obviously, there are limits (to the data’s application) but we took steps to insure these women were healthy, to make sure none were suffering from psycho-pathology and to ensure that they had typical menstrual cycles,†he said.
There were two feeding plans in the study. In the first pattern, the women were fed diets that averaged about 587 milligrams of calcium daily along with a placebo capsule. The second plan offered the same amount of dietary calcium but also included a supplement containing about 700 milligrams calcium carbonate.
“Nine out of 10 women showed a positive effect of the calcium in terms of improving their mood state,†Penland said. Similarly positive results were found for other PMS-related conditions.
The women’s state was measured by responses to a standardized test known as the Moos Menstrual Distress Questionnaire.
If the USDA’s calcium findings are eventually accepted by the medical community then the next question is whether women can get PMS relief by using mineral supplements, by adding calcium-rich foods to the diet or both.
Weaver, of Purdue, said that calcium carbonate supplements, such as those used in the USDA study, are as easy for the body to absorb as a glass of milk.
The National Nutritional Foods Assn., a Costa Mesa-trade group that represents supplement manufacturers, was also surprised to hear of the USDA’s study results.
“These results are new to me,†said Burton Kallman, Ph.D., science and technology director for the National Nutritional Foods Assn. “Considering the problem and how extensive it is, anything that offers proven relief should be welcomed in the medical (community). If the data is valid then it is very encouraging.â€
