Ginseng Does Not Adversely Affect Blood Pressure, Renal Function

TORONTO--Long-term intake of North American ginseng does not appear to adversely impact renal function or 24-hour blood pressure, according to a new study in Hypertension (47, 4:791, 2006). Researchers from St. Michael's Hospital and the University of Toronto conducted a randomized, placebo-controlled, double blind, crossover trial in 52 hypertensive individuals to determine the impact of 12 weeks of North American ginseng supplementation on 24-hour blood pressure and overall renal function. The study protocol included a four-week placebo run-in, 3 g/d of ginseng or placebo for 12 weeks, an eight-week washout, and a 12-week crossover treatment.

Forty participants completed the trial, with three removed from the main analysis for outside influencers. In those subjects who completed the trial, 12-week ginseng treatment had a neutral effect on all blood pressure parameters compared to placebo. In addition, ginseng did not affect serum cystatin C levels, a marker of renal function. The researchers concluded despite observational evidence suggesting a link between ginseng intake and hypertension, this trial showed no such association.