Approximately one-third of adults in America have high blood pressure, known medically as hypertension. Because there are no symptoms, they don't know that they have it. In fact, many people have high blood pressure for years without knowing it. Uncontrolled high blood pressure can lead to stroke, heart attack, heart failure or kidney failure. This is why high blood pressure is often called the "silent killer." The only way to tell if you have high blood pressure is to have your blood pressure checked. Hypertension is defined as blood pressure above 140/90 mm Hg, while healthy blood pressure is lower than 120/80 for an adult.

Taking coenzyme Q-10 with other high blood pressure medication seems to provide an additional blood pressure lowering effect. You should check with your doctor before taking the supplement.Diets and/or supplements rich in omega-3 fatty acids (including alpha-linolenic acid and flaxseed oil) lower blood pressure in people with hypertension.

Taking fish oil or cod liver oil seems to lower blood pressure in patients with mild hypertension.

Taking calcium supplements seems to modestly reduce blood pressure in patients with or without hypertension. Calcium seems to be more effective for salt-sensitive people and people with low dietary calcium intake.

There is some evidence that taking garlic can modestly reduce blood pressure.