Hypertension, or high blood pressure, increases the risk for several health conditions, including heart disease, kidney failure and stroke. A blood pressure reading is given in two numbers such as 120/80. The top number in blood pressure reading, known as systolic blood pressure, refers to the pressure when the heart contracting. On the other hand, the bottom number, known as diastolic blood pressure, refers to the heart when it's resting. Research indicates that quercetin might help improve blood pressure levels.
Quercetin
Quercetin belongs to a class of antioxidant compounds called flavonoids, which scavenge free radicals that might cause disease and illness. In addition, quercetin also has anti-inflammatory properties that help reduce inflammation in the body. Quercetin, which can be found in foods, such as red onions, olive oil, blueberries, blackberries, apples and grapes, is also available in supplement form.
Hypertension
Researchers from the University of Utah studied the effects of quercetin supplementation in subjects with pre-hypertension and hypertension. For 28 days, participants were assigned to either 730mg of quercetin or a placebo. Scientists reported in the November 2007 issue of the "Journal of Nutrition" that hypertensive subjects, but not pre-hypertensives, consuming quercetin experienced decreases in systolic and diastolic blood pressure compared to those who were administered a placebo.
Blood Pressure
Scientists from Christian-Albrechts-University in Germany examined the impact of quercetin supplementation on blood pressure in overweight subjects at risk for cardiovascular disease. Participants were randomly assigned either 150mg of quercetin or a placebo for six weeks. At the end of the study, which was published in the October 2009 issue of the "British Journal of Nutrition," researchers observed that the quercetin group experienced reductions in systolic blood pressure compared to the placebo group.
Side Effects and Interactions
Quercetin is generally considered safe. However, some side effects have been reported, including headache and stomach upset. In addition, quercetin might interact with certain medications such as blood thinners, cyclosporine and corticosteroids. Consult your health care provider before taking any quercetin supplements.
References
- University of Maryland Medical Center: Quercetin
- "Journal of Nutriton": Quercetin Reduces Blood Pressure in Hypertensive Subjects; R.L.Edwards et al; November 2007
- PubMed.gov: Quercetin Reduces Systolic Blood Pressure and Plasma Oxidized Low-Density Disease Risk Phenotype: a Double Blinded, Placebo-Controlled Cross-Over Study; S.Egert et al; October 2009
