Garlic has a wide range of well-documented effects, including helping to lower blood pressure. Studies showing a positive effect of garlic and garlic preparations are those that deliver a sufficient dosage of allicin. In double-blind studies with garlic preparations providing a daily dose of at least 10 mg allicin, blood pressure readings dropped with typical reductions of 11 mm Hg for the systolic and 5.0 in the diastolic within a 1 to 3-month period. To get enough allicin, eat 1 to 4 cloves of fresh garlic a day. If you want to avoid garlic breath in public, add minced fresh garlic to your salad dressing in the evening at dinner.
Why it works: All of the beneficial effects of garlic are attributed to its sulfur-containing compounds: allicin, diallyl disulfide, diallyl trisulfide, and others. Allicin is mainly responsible for the pungent odor of garlic. It is formed by the action of the enzyme alliinase on the compound alliin. The enzyme is activated by heat, oxygen, or water. This accounts for the fact that cooked garlic, odorless supplements, "aged garlic preparations," and garlic oil products produce neither as strong an odor as raw garlic nor nearly as powerful medicinal effects as raw fresh garlic.
Raw Garlic Or Dry Garlic?
According to the Linus Pauling Institute, when you crush, chop or chew raw fresh garlic, the enzyme called alliinase is released, which starts a series of reactions resulting in the formation of allicin. Raw fresh or dried garlic may provide you with the most allicin. The allicin potential decreases with age or heat-treatment
of the garlic. Researchers say that due to the instability of allicin, forms of garlic other than fresh raw or dried garlic, such as aged or cooked garlic, may have less allicin-forming potential. The instability of allicin is also the reason pure allicin is not available as a supplement.
What Is The Correct Dosage?
Researchers of a study published in 2013 in Pakistan Journal of Pharmaceutical Sciences divided individuals diagnosed with hypertension into groups, each with a different dosage of garlic - 300, 600, 900, 1200 or 1500 milligrams of garlic per day - or a placebo or blood pressure medication. They found that all the garlic dosages decreased blood pressure comparatively as much as the blood pressure medicine did, and that there was a greater reduction in blood pressure with the higher doses of garlic and with a longer duration of treatment. In the review in BMC Cardiovascular Disorders, the authors found that most of the studies that showed garlic's blood pressure-lowering effect used a dosage of 600 to 900 milligrams of garlic per day.
How Much Should I Eat?
You may be able to lower your blood pressure by consuming 1/3 to 1 1/2 grams of fresh raw or dried garlic daily. Since most garlic cloves are about 3 grams, this is equivalent to 1/10 to 1/2 a garlic clove daily. Your blood pressure may be lowered more if you eat more. Speak with your doctor and dietitian about making changes to your diet as consuming garlic in excess may be detrimental, especially if you are on certain medications. Reference