Potassium helps your kidneys get rid of more sodium through your urine. This in turn lowers your blood pressure. High potassium containing greens are spinach, fenugreek, beet greens, lettuce, kale, turnip greens. Canned vegetables often have added sodium. But frozen vegetables contain as many nutrients as fresh vegetables, and they’re easier to store. You can also blend these veggies with bananas and nut milk for a healthy, sweet green juice.