What if menstruation pain could be relieved with an old standby supplement?
Women suffering from period cramps because of dysmenorrhea—otherwise known as painful menstruation—may find relief using vitamin D supplements. A new meta-analysis from Taiwan found that the vitamin offers pain relief without the downsides of traditional painkillers.
Primary dysmenorrhea refers to the cramps that a woman gets before or during her period that are caused by uterine contractions. Secondary dysmenorrhea is menstrual pain caused by something else, such as pelvic inflammatory disease, endometriosis, uterine fibroids, abnormal pregnancy, infection, tumors, or polyps in the pelvic cavity.
“Dysmenorrhea represents a significant global health burden that requires attention,” the research team wrote, adding that health care costs for patients with dysmenorrhea are 2.2 times higher than for the general population.
Why Vitamin D Works for Cramps
The meta-analysis, which included a review of 11 studies involving nearly 700 subjects, found that vitamin D supplements significantly decreased pain caused by primary dysmenorrhea. The researchers noted, however, that an analysis of subgroups found that supplementing did not have a clinically significant effect on cases of secondary dysmenorrhea, although it still helped with pain to some degree.
Typically, dysmenorrhea is treated with nonsteroidal anti-inflammatory drugs, including aspirin and ibuprofen. Other treatment options include oral contraceptives to help regulate hormones, diet changes, exercise, heating pads, or hot baths or showers. In extreme cases, surgery may be considered.
The researchers theorized that vitamin D alleviates cramps because the ovaries, uterus, placenta, and pituitary gland all have vitamin D receptors. When a woman has lower vitamin D levels—which researchers observed was the case for this phase of the menstrual cycle—she’ll experience an increase in inflammatory cytokines and prostaglandins, exacerbating the intensity of dysmenorrhea symptoms. Vitamin D supplementation, however, can suppress the expression of this inflammation in parts of the uterus, thereby reducing the intensity of symptoms.
How Much Vitamin D to Take
The recommended daily intake for adults is 4,000 international units (IU) per day, though many experts insist this is low. According to the study, the recommended daily vitamin D intake is 50,000 IU for eight weeks for individuals being treated for vitamin D deficiency. However, the research team noted that the amount required for treating dysmenorrhea was “controversial.” Some of the studies that they reviewed suggested that women take supplements daily, while others suggested weekly. Two studies recommended vitamin D supplements once daily for five days during a woman’s menstrual cycle.
Although researchers found that some of the studies’ dosages exceeded the recommended 50,000 IU per week, at roughly 200,000 IU per menstrual cycle, all of the participating women were deemed vitamin D deficient, and none had post-treatment serum vitamin D levels that surpassed the limit recommended by study guidelines. At the end of the studies, participants’ vitamin D levels did not exceed 375 nanomoles per liter (nmol/L), which is considered very high and can cause toxicity symptoms.
According to the National Institutes of Health, it is possible to take too much vitamin D. Very high levels can lead to nausea, vomiting, muscle weakness, confusion, pain, loss of appetite, dehydration, and kidney stones.
Talking with a health care professional or pharmacist before starting dietary supplements is essential, as even standard vitamins can interact with medications. For example, vitamin D interacts with certain weight-loss drugs, cholesterol-lowering statins, steroids, and thiazide diuretics.
