The U.S. Department of Health and Human Services published a report titled "Your Guide to a Healthy Heart" in Dec. 2005, stating:

“Certain mineral-rich foods can help keep blood pressure levels healthy… Calcium and magnesium are two other minerals that may help to prevent high blood pressure, as well as improve health in other ways. Low-fat or fat-free milk and milk products are rich sources of calcium.”

Dec. 2005 - “Your Guide to a Healthy Heart”