Eight women and seven men with high blood pressure were given 250 mL (just over a cup) of water or beetroot juice, then monitored over 24 hours in a small study published in the American Heart Association journal Hypertension. Those who drank the beetroot juice experienced a drop on systolic blood pressure—the top number—by an average of 11.2 points and experienced an overall lower systolic blood pressure. Beets are just one of several vegetables—including lettuce, spinach, kale, turnips, radishes, carrots, and chard—high in dietary, or inorganic, nitrate. When digested, nitrate become nitric oxide, a gas in the blood that can widen your blood vessels and aid in blood flow. While the researchers are uncertain as to whether the effect can be maintained on a long-term basis, the study showed that this small, 8-ounce dose raised nitrate levels 1.5 times in the patients with hypertension—in a relatively inexpensive way.  Want to give your diet a healthy does of dietary nitrate? Give this Blueberry-Almond Smoothie a try—it contains beets and carrot juice, both good sources of nitrate: Ingredients1/2 cup unsweetened carrot juice1/4 cup frozen blueberries1/4 cup peeled and grated raw beet1/4 cup unsweetened applesauce1/4 cup unsalted raw whole almonds1/3 cup ice cubes, 1/2 teaspoon fresh lime juiceDash of ground ginger.  Blend ingredients together and enjoy! Makes one serving. More from Prevention: 13 Ways To Lower Blood Pressure Naturally