Hypertension, commonly known as high blood pressure, affects one in three American adults, according to the University of Maryland Medical Center. Sometimes referred to as the silent killer, hypertension is usually symptom-free and increases the risk of stroke and heart attack. If your average systolic blood pressure consistently measures 140 mmHg or above, or your diastolic blood pressure is 90 mmHg, or over, you have hypertension. You can help to prevent or reduce high blood pressure by cutting your alcohol intake and eating a low sodium diet. However, you may also need to take antihypertensive medicines. Garlic may also help to lower high blood pressure, but it should not be used in place of dietary modifications or medicines your doctor prescribes. Talk to your doctor before using it.
Properties and Potential Benefits
Also known as Allium sativum, garlic is a popular food flavoring that is also sometimes used as an herbal medicine for a number of conditions including cardiovascular disease, atherosclerosis and hypertension. It contains a host of active compounds including enzymes and volatile oils. However, the Memorial Sloan-Kettering Cancer Center notes that a compound known as alliin likely confers garlic's therapeutic effects. Garlic may help to lower high blood pressure by dilating the blood vessels, allowing blood to flow more freely.
Administration
Although you can eat garlic raw, you may prefer to take it in capsules or tablets. The UMMC website suggests taking 400 mg of a standardized extract of garlic two or three times daily to help lower high blood pressure. If you prefer to eat fresh raw garlic instead of taking tablets, RxList states that eating 4 grams daily, roughly equivalent to one clove of garlic, has been used to treat hypertension.
Scientific Evidence
A clinical study published in the October 2010 issue of "Maturitas" notes that taking 960 mg of aged garlic extract daily for 12 weeks is superior to placebo in lowering systolic blood pressure in patients with treated but uncontrolled hypertension. The authors add that garlic may even be as effective as prescription blood pressure medicines. An analysis of clinical data from 11 clinical trials, published in the June 2008 issue of "BMC Cardiovascular Disorders" concludes that garlic is superior to placebo in reducing blood pressure in people with hypertension.
Safety Considerations
RxList notes that garlic is likely safe for most people but adds that it may cause side effects, including diarrhea, body odor, a burning sensation in the mouth and bad breath. However, garlic is not a suitable antihypertensive for everyone. Its use is contraindicated in HIV and AIDS, bleeding disorders and stomach problems. Don't take a garlic supplement if you are pregnant or breastfeeding. Garlic may also interact with other drugs you are taking, including anticoagulants and contraceptives.
References
- University of Maryland Medical Center: Hypertension
- Memorial Sloan Kettering Cancer Center: Garlic
- RxList: Garlic
- "Maturitas"; Aged Garlic Extract Lowers Blood Pressure in Patients With Treated But Uncontrolled Hypertension: A Randomised Controlled Trial; K. Reid et al.;October 2010
- "BMC Cardiovascular Disorders"; Effect of Garlic on Blood Pressure: A Systematic Review and Meta-Analysis; K. Reid et al.; June 2008
