In a Control trial, of 810 adult over the duration of the study, a reduction of one 12-oz serving of sugar-sweetened beverages per day was associated with an average of 1.8 mmHg (Units millimetre(s) of mercury [a unit of pressure equal to the pressure that can support a column of mercury 1 millimetre high]) reduction in systolic blood pressure and an average of 1.1 mmHg reduction in diastolic blood pressure.
Source
Future Cardiol. 2010 Nov;6(6):773-6. doi: 10.2217/fca.10.92. Sugar-sweetened beverages and hypertension. Feig DI1