August 3, 2008 -  Garlic has been known to help keeping cholesterol under control. A new study is now suggesting supplements of the pungent herb may be useful in reducing high blood pressure as well.

The study, which itself was a review of 11 pervious studies, found regular intake of garlic supplements to be useful in reducing high blood pressure levels. The researchers from The University of Adelaide in South Australia analyzed 11 studies where patients were assigned to either take garlic supplements or a placebo.

In a majority of the 11 studies, the doses of garlic supplementation were 600 mg to 900 mg daily. Most participants also took it on powdered form.

Overall garlic supplements were responsible for reducing systolic blood pressure by 4.6 mm Hg, on average. When the researchers examined patients with high blood pressure only, they found garlic supplements reduced systolic blood pressure by 8.4 mm Hg, on average, and diastolic blood pressure by 7.3 mm Hg.

Systolic blood pressure denotes the upper reading, while diastolic blood pressure denotes lower reading. Normal blood pressure levels are usually considered to be 120/80 mm of Hg (Mercury).

In the current study researchers found the higher a person's blood pressure levels, the more significant effect garlic supplements had.

Reporting in the journal BMC Cardiovascular disorders, lead researcher Dr Karin Ried, of Adelaide University in South Australia, and colleagues said the effects of garlic were similar to widely used anti0hypertensive medicines like beta blockers.

Called Allium sativum, garlic is one of the most studied herbs in relation to heart benefits. Since times immemorial its potential heart benefits have been touted, but no conclusive evidence has emerged.

According to the U.S. National Center for Complementary and Alternative Medicine, garlic is also used to prevent certain types of cancer, including stomach and colon cancers, but there is no scientific evidence to support this theory. Garlic might also be used in preventing the development of atherosclerosis, which hardens arteries and is the first step in the development of heart disease.

Garlic must be used with caution in people who have a bleeding disorder, because it is a powerful blood thinner. Other side effects include bad breath, body odor, heartburn, upset stomach, and allergic reactions.

If results of the above study are duplicated in larger trials, then people with high blood pressure may have a natural vegetable/herb for reducing their hypertension status.