One clinical trial conducted in 2005 at the University of Utah with 41 pre-hypertensive or stage 1 hypertensive subjects suggest that quercetin supplementation may help control high blood pressure. Quercetin and other flavonoids help block the receptor for angiotensin II, the hormone that triggers the constriction of arteries.

Pre-hypertension was defined as having a blood pressure of 120–139/80–89, while those with 140–159/90–99 were categorized with stage 1 hypertension (as per clinically accepted guidelines at the time).

Potential study candidates were carefully screened for chronic disease or other possible interfering factors (i.e., blood pressure medication or other supplementation), and only non-smokers who were not pregnant or nursing were allowed to complete the study.

Participants were randomly divided into two groups, and for four weeks, took 365 mg of quercetin twice a day (based on in vivo animal studies) or a placebo. Results demonstrated that quercetin supplements reduced both systolic and diastolic pressures by five to seven points for those suffering from hypertension, regardless of age, gender, or weight, with no changes in those with borderline normal blood pressures. Given the statistical data, these reductions are considered significant and are associated with decreased risks of mortality from stroke and heart disease.

My recommendations for HBP include Magnesium (400 to 800 mg daily), Coleous Forskolhi, CoQ10 (400 mg daily or higher) and Quercetin, (365 mg twice a day).



References:
Serban MC, Sahebkar A Effects of Quercetin on Blood Pressure: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. J Am Heart Assoc. 2016 Jul 12;5(7). pii: e002713. doi: 10.1161/JAHA.115.002713.

Rodríguez-Moran M, Guerrero-Romero F. Hypomagnesemia and prehypertension in otherwise healthy individuals. Eur J Intern Med. 2014 Feb;25(2):128-31. doi: 10.1016/j.ejim.2013.08.706. Epub 2013 Sep 11.