The soluble fiber in oats is good for cholesterol reduction, which in turn can help your BP. But the big payoff comes from the bananas and raisins. Both fruits are loaded with blood-pressure-lowering potassium. Studies show that if you don’t get your recommended 3,500 mg of potassium daily, you’re setting yourself up for high blood pressure. Wash the oatmeal down with tea, which is rich in flavonoids, compounds that improve the ability of blood vessels to relax.