RESEARCH · November 24, 2014
TAKE-HOME MESSAGE
- In this double-blind, placebo-controlled study, researchers randomized 68 patients with hypertension to receive daily dietary nitrate or placebo to determine effects on blood pressure. Dietary nitrate significantly reduced clinic, ambulatory, and home blood pressure over a 4-week period (P < .001). There was no significant evidence of tachyphylaxis.
- Researchers suggest that dietary nitrate may be an affordable, adjunctive treatment for patients with hypertension.
Expert Comment
Cardiology
Paul D Thompson MD
Dietary supplements are popular with many of our patients. There is little evidence that they work, with occasional exceptions, such as Chinese red rice yeast, which contains mevacolins that can reduce low-density lipoprotein cholesterol (LDL-C) levels. Results of a randomized, controlled clinical trial published in Hypertension suggest that nitrate-containing beet root juice can produce sustained reductions in blood pressure. The investigators gave 34 hypertensive patients 250 mL a day of natural beet root juice, which contains NO3−, and 34 other hypertensive patients 250 mL a day of nitrate-free beet root juice. Blood pressure was determined by clinic, ambulatory, and home measurements. The nitrate-containing beet root juice produced significantly greater reductions in systolic and diastolic blood pressures by all measurement techniques than placebo, and this effect persisted for the 4 weeks of the trial. Furthermore, endothelial function increased and arterial stiffness decreased only after the nitrate containing beet root juice was taken. These results suggest that dietary beet root juice may provide an alternative blood pressure treatment for those who prefer more “natural” treatments.
Primary Care
David Rakel MD, FAAFP
ABSTRACT
Single dose administration of dietary inorganic nitrate acutely reduces blood pressure (BP) in normotensive healthy volunteers, via bioconversion to the vasodilator nitric oxide. We assessed whether dietary nitrate might provide sustained BP lowering in patients with hypertension. We randomly assigned 68 patients with hypertension in a double-blind, placebo-controlled clinical trial to receive daily dietary supplementation for 4 weeks with either dietary nitrate (250 mL daily, as beetroot juice) or a placebo (250 mL daily, as nitrate-free beetroot juice) after a 2-week run-in period and followed by a 2-week washout. We performed stratified randomization of drug-naive (n=34) and treated (n=34) patients with hypertension aged 18 to 85 years. The primary end point was change in clinic, ambulatory, and home BP compared with placebo. Daily supplementation with dietary nitrate was associated with reduction in BP measured by 3 different methods. Mean (95% confidence interval) reduction in clinic BP was 7.7/2.4 mm Hg (3.6-11.8/0.0-4.9, P
Hypertension
Dietary Nitrate Provides Sustained Blood Pressure Lowering in Hypertensive Patients: A Randomized, Phase 2, Double-Blind, Placebo-Controlled Study
Hypertension 2014 Nov 24;[EPub Ahead of Print], V Kapil, RS Khambata, A Robertson, MJ Caulfield, A Ahluwalia