Published May 22, 2012 CARDIOVASCULAR Large Vitamin C Doses May Reduce Blood Pressure By Staff US Pharm. 2012;37(5):1. Baltimore, MD—Taking big doses of vitamin C may modestly lower blood pressure, according to an analysis of data from 29 previously published clinical trials. The trials, comprising years of research, all reported systolic and/or diastolic blood pressure values and compared vitamin C intake with placebo. Scientists at Johns Hopkins University School of Medicine found that, in the short term, blood pressure was reduced by nearly 4 mmHg (nearly 5 mmHg in subjects with hypertension) in subjects taking an average of 500 mg of vitamin C daily. This amount of vitamin C is about five times the recommended daily requirement. The scientists say that more research is needed before vitamin C is recommended as a treatment for high blood pressure. To comment on this article, contact rdavidson@uspharmacist.com.