Garlic, the smelly, unassuming bulb that plays a role in the flavor of so many dishes, has a history of at least seven millennia of human use. The ancient Egyptians documented its function as a medicine and left it in their pyramids and tombs.
And its medicinal properties have also been recorded in the medical literature of the ancient Greeks, Chinese and Romans, and in Indian Ayurvedic texts.1
Garlic’s antimicrobial effect has long been recognized by folk medicine. In Italy, garlic was tied around the necks of children to ward off colds.
One childhood wearer noted that it worked by keeping everyone (including the contagiously ill) from coming around. Garlic’s reputation for protection against vampires could be attributable to a similar effect, perhaps because of their preternatural sense of smell.
As is usually the case with folk remedies, scientific investigations have not only validated many of the benefits attributed to garlic, but have uncovered some not previously identified.
The Magic of Garlic Lies in Allicin
Fresh garlic is the source of a sulfur-containing compound known as allicin that is formed when garlic is crushed, chopped, or chewed. Allicin, which is responsible for garlic’s pungent scent, rapidly degrades into other compounds.
The antiviral effects of garlic are attributable to its allicin content.
Garlic is Truly Heart Healthy
Allicin may also be the component of garlic responsible for its blood-thinning effect.2 A study published in 1978 involving healthy adults who ingested garlic, found a reduction in platelet aggregation in blood samples.3 Platelets are cells that clump together to form blood clots.
Another cardiovascular benefit associated with garlic is cholesterol reduction, which was documented as early as 1979.4
In 1981, the American Journal of Clinical Nutrition reported a study of individuals who experienced a reduction in cholesterol and triglycerides after ten months of garlic oil consumption.5
In another study, participants whose lipids were elevated following a high fat diet saw a reduction in lipids after garlic supplementation.6 When administered to patients with hypertension, garlic tablets reduced blood pressure as well as the antihypertensive drug atenolol.7
Garlic Fights Cancer
Like most plants, garlic intake has been linked with cancer protection.
In an area of China with high rates of stomach cancer, those with the highest intake of garlic and onions had a 40% lower risk of the disease than those with the lowest intake.8
A recent Chinese study found that diallyl disulfide reduced the ability of esophageal cancer cells to survive.9Another garlic compound, S-allyl mercaptocysteine, hindered the growth of breast cancer cells.10
Similarly, a garlic extract called S-allylcysteine inhibited the proliferation of ovarian cancer cells11 and garlic oil has shown comparable effects in pancreatic cells.12
Furthermore, an analysis of nine studies found a 23% reduction in the risk of prostate cancer in association with high garlic intake.13
Garlic Protects the Brain and Supports Longevity
Fractions derived from aged garlic extract have shown protective effects against the toxicity caused by amyloid-beta, suggesting that the compounds may have potential in Alzheimer’s disease research.14
And a breaking study in roundworms has shown that garlic extract extended lifespan by 20%, suggesting its candidacy for further life extension research.15
Supplement With Garlic
Raw garlic can be chopped and added to a number of foods, or placed in empty capsules and swallowed. There are several garlic supplements on the market that retain their allicin content, which is a big benefit for those who don’t enjoy consuming raw garlic.
A journal article titled “Garlic revisited: therapeutic for the major diseases of our times?” predicted that “Garlic may play an invaluable role in the prevention and therapy of the major causes of death.”16
Despite its stinky reputation, garlic still comes up smelling like a rose.
- J Nutr. 2001 Mar;131(3):951S-954S.
- Thromb Res. 1986 Dec 15;44(6):793-806.
- Atherosclerosis. 1978 Aug;30(4):355-60.
- Indian J Physiol Pharmacol.1979 Jul-Sep;23(3):211-4.
- Am J Clin Nutr. 1981 Oct;34(10):2100-3.
- Nahrung. 1984;28(2):159-63.
- Pak J Pharm Sci. 2013 Sep;26(5):859-63.
- J Natl Cancer Inst. 1989 Jan 18;81(2):162-4.
- Oncol Rep. 2014 Oct;32(4):1748-56.
- BMC Complement Altern Med. 2014 Jul 28;14:270.
- Acta Pharmacol Sin. 2014 Feb;35(2):267-74.
- Asian Pac J Cancer Prev. 2013;14(10):5905-10.
- Asian Pac J Cancer Prev. 2013;14(7):4131-4.
- BMC Complement Altern Med. 2013 Oct 18;13:268.
- J Nutr Biochem. 2015 Aug;26(8):808-17.
- J Natl Med Assoc. 1988 Apr;80(4):439-45.