Hypertension, or high blood pressure, is sometimes called "the silent killer" because it can cause severe health problems, such as heart attack and stroke, without causing symptoms beforehand. Hypertension is defined as having blood pressure over 140/90, but you might be at risk for developing the condition if your blood pressure is over 120/80. Medications and lifestyle changes might reduce your blood pressure. One popular alternative therapy is to take garlic, either as part of your diet or as a supplement. Like all dietary supplements, garlic can have side effects and contraindications. Do not take any supplement without speaking to your physician.
Evidence
According to the University of Maryland Medical Center, taking garlic orally might reduce both your systolic and diastolic blood pressure. This is true whether you have high or normal blood pressure. Medline Plus states that it might reduce your blood pressure by 7 percent to 8 percent. Dr. Ellen Tattelman of the Albert Einstein College of Medicine of Yeshiva University, however, points out in the "American Family Physician" that there is some evidence that garlic does not significantly lower blood pressure. Because garlic does potentially offer heart-health benefits, talk to your doctor about whether taking garlic supplements to lower your blood pressure makes sense for you.
Dosage
Eating one or two cloves of garlic per day is considered safe for most adults, says Dr. Tattelman, and provides you with 1 or 2 g of garlic. The University of Maryland Medical Center recommends consuming between 2 and 4 g of fresh garlic if it is to be used medicinally. If you prefer to take your garlic as a supplement, take between 600 and 1,200 mg of aged garlic extract each day, divided into several doses; 1,200 mg of freeze-dried garlic, split into three doses; or 4 ml of fluid extract daily. Speak to your physician about the exact dose that is right for you.
Contraindications
Certain medication might react with garlic. If you are taking a blood-thinner, for example, the garlic might enhance its effects, leading to excessive bleeding or slowed blood-clotting. Use caution if you are taking birth control pills along with the garlic. Garlic can reduce the amount of time it takes for your body to process the estrogen in birth control pills, possibly leading to an unintended pregnancy. Other medications that you should not take with garlic include medications for HIV or AIDS, isoniazid and saquinavir. If you are on any medications, ask your doctor before taking garlic supplements.
Considerations
While taking garlic, do not stop taking or take less of any high blood pressure medication that your doctor has prescribed. If you think that you might be able to discontinue or reduce your medication, talk to your doctor before making any changes to your regimen. If your doctor has recommended lifestyle changes, such as exercising more, losing weight or quitting smoking, continue to make these changes even though you are taking garlic for your blood pressure.
