A recent study reveals aged garlic extract might be beneficial for health as it lowers blood pressure of the study participants who have hypertension.

The study led by Dr Karin Ried from University of Adelaide's Discipline of General Practice involving a 12-week trial with 50 participants, found that garlic is effective in lowering their blood pressure and could be used complementary to conventional drugs for hypertension.

Hypertension affects about 30 per cent of Australian adults, yet only half are taking blood pressure medication and 60 per cent of those on medication do not have their blood pressure adequately regulated.

Dr Ried said, There is a large proportion of people out there who are on medication and some people are on four different types but they still have high blood pressure, it is uncontrolled.

Aged garlic extract is specifically effective for lowering blood pressure as opposed to raw, cooked garlic or garlic powder.

Garlic powder is not as stable and poses a problem as you're not sure about the dose you're supposed to take and garlic oil does not have the active substance required.

Aged garlic which is prepared using a special process is the best choice and it can be purchased at any shops here, she said.

According to Dr Ried, the participants's blood pressure was dropped down below the hypertension threshold when they were given garlic supplement.

She said, ... so garlic might be a good complementary treatment option to control hypertension.

The systolic blood pressure of participants which was initially above 140 who took four aged garlic extract capsules per  day was lowered by an average systolic blood pressure of 10.2mmHg compared to the control group who were on placebo.

The anti-hypertensive effect of garlic is said due to its ability to stimulate the production of nitric oxide and hydrogen sulphide - both responsible in relaxing blood vessels.