New York- An analysis of more than 30 existing studies said magnesium supplements taken daily for three months may result in slightly lower blood pressure.

Previous evidence has suggested that magnesium deficiency may be related to cardiometabolic disorders, including high blood pressure, said lead author Yiqing Song.

“Taking oral magnesium supplements regularly can help lower blood pressure and can be considered as an inexpensive, safe, and adjuvant antihypertensive therapy,” said Song, of the Richard M. Fairbanks School of Public Health at Indiana University in Indianapolis.

But magnesium supplements can cause gastrointestinal symptoms, and may interfere with medications, he told Reuters Health by email.

“Patients with heart disease, kidney disease, liver disease or other critically ill conditions should not take magnesium supplements without their doctor’s consent and supervision,” Song added.

The researchers combined data from 34 clinical trials that included a total of more than 2,000 people. Based on those results, they found that taking daily supplements of about 368 milligrams of magnesium for about three months seemed to reduce blood pressure measurements by between one and two millimeters of mercury (mm Hg).

Normal blood pressure readings are 120 mm Hg systolic (the top number) or less, and 80 mm Hg diastolic (the bottom number) or less. Hypertension, or high blood pressure, is usually defined as a systolic reading of 140/90 mm Hg or higher.

About 70 million adults in the U.S., or one in three, have high blood pressure, according to the Centers for Disease Control and Prevention.