Posted on Jun 03, 2014, 6 a.m.
Abundant in nitrate, spinach – and apples – plentiful in flavonoids, raise nitric oxide in the body.
Nitric oxide (NO) is an important molecule for cardiovascular and cognitive health, as it exerts effects on blood flow and blood vessel function. Catherine Bondonno, from the University of Western Australia (Australia), and colleagues enrolled 30 healthy female and male volunteers, and screened them through a medical history questionnaire, electrocardiography, BMI, height and weight, blood pressure, and fasting blood samples. Subjects were randomly assigned into one of four interventions—a) apple: high flavonoid low nitrate; b) spinach: low flavonoid high nitrate; c) apple + spinach: high flavonoid high nitrate; d) control: low flavonoid low nitrate. Measuring plasma NO status in plasma, urine and saliva, and assessing cognitive performance and mood via standardized scales, separately the apples and spinach increased markers of NO in the plasma; and the spinach alone, and the apple + spinach combination, significantly improved markers of NO in saliva and urine as well. The study authors conclude that: “flavonoid-rich apples and nitrate-rich spinach augmented [nitric oxide] status acutely with no concomitant improvements or deterioration in cognitive function and mood.”
Bondonno CP, Downey LA, Croft KD, Scholey A, Stough C, Yang X, Considine MJ, Ward NC, Puddey IB, Swinny E, Mubarak A, Hodgso. “The acute effect of flavonoid-rich apples and nitrate-rich spinach on cognitive performance and mood in healthy men and women.” Food Funct. 2014 Apr 23;5(5):849-58.