The bioflavonoid nutrient quercetin is best-known for its anti-cancer prowess and its ability to optimise the body’s utilisation of vitamin C. Now, according to a study from the University of Utah, published in The Journal of Nutrition, it appears that taking a daily supplement of 730mg of quercetin can also significantly lower both systolic and diastolic blood pressure in people with hypertension. Why? Study author Randi Edwards suggests that quercetin may reduce the production of angiotensin II, a molecule that constricts blood vessels and so increases blood pressure.