The NPJ intervention decreased systolic and diastolic blood pressures ( systolic blood pressure : 128 1 to 124 2 mm Hg ; diastolic blood pressure : 79 1 to 76 1 mm Hg ) , whereas the HPJ intervention increased erythrocyte superoxide dismutase ( SOD ) activity ( 17.7 1.5 to 23.1 1.7 U/mg hemoglobin ) .