24 Possible Benefits of Garlic

Garlic is beneficial for heart health & blood sugar regulation. It may have significant antibiotic properties. It contains allicin, a plant compound that may inhibit the growth of human mammary, endometrial, & colon cancer cells. Moreover, garlic has historically been used medicinally for preventive & curative remedies, with roots tracing back to ancient Egyptians, Babylonians, Greeks, Romans, and Chinese.

Garlic Contains Compounds With Potent Medicinal Properties. Scientists now know that most of its health benefits are caused by sulfur compounds formed when a garlic clove is chopped, crushed, or chewed. Perhaps the most famous of those is known as allicin. Other compounds that may play a role in garlic’s health benefits include diallyl disulfide and s-allyl cysteine. The sulfur compounds from garlic enter the body from the digestive tract and travel all over the body, where it exerts its potent biological effects.

Garlic Is Highly Nutritious But Has Very Few Calories. Garlic is low in calories and rich in vitamin C, vitamin B6, and manganese. It also contains trace amounts of various other nutrients such as selenium, fiber, calcium, copper, potassium, phosphorus, iron, and vitamin B1.

Garlic Can Combat Sickness, Including the Common Cold. Garlic is known to boost the function of the immune system. One large, 12-week study found that daily garlic reduced the number of colds by 63% compared to a placebo. The average length of cold symptoms was also reduced by 70%, from 5 days in the placebo group to just 1.5 days in the garlic group. Another study found that a high dose of aged garlic extract (2.56 grams per day) reduced the number of days sick with cold or flu by 61%. However, one review concluded that the evidence is insufficient and more research is needed. Despite the lack of strong evidence, adding garlic to your diet may be worth trying if you often get colds.

A team of researchers from St. Joseph Family Medicine Residency, Indiana, carried out a study titled “Treatment of the Common Cold in Children and Adults,” published in American Family Physician. They reported that “Prophylactic use of garlic may decrease the frequency of colds in adults, but has no effect on the duration of symptoms.” Prophylactic use means using it regularly to prevent disease. Though there is some research to suggest that raw garlic has the most benefits, other studies have looked at overall allium intake, both raw and cooked, and have found benefits. Therefore, you can enjoy garlic in a variety of ways to reap its advantages.

The Active Compounds in Garlic Can Possibly Effective for Reducing High Blood Pressure. Garlic reduces blood pressure in patients with high blood pressure (hypertension). Aged garlic extract reduces blood pressure by increasing calcium and reducing C-reactive protein levels, which cause inflammation and elevated blood pressure. On the other hand, sulfur deficiency may play a role in hypertension. Allicin is a sulfur compound in garlic that lowers blood pressure by increasing hydrogen sulfide concentrations. Hydrogen sulfide relaxes blood vessels (through nitric oxide) and prevents blood vessel constriction (by endothelin-1).

Cardiovascular diseases like heart attacks and strokes are the world’s biggest killers. High blood pressure, or hypertension, is one of the most important drivers of these diseases. Human studies have found garlic to have a significant impact on reducing blood pressure in people with high blood pressure. In one study, 600–1,500 mg of aged garlic was just as effective as the drug Atenolol at reducing blood pressure over a 24-week period. The amount needed is equivalent to about four cloves of garlic per day.

Possibly Effective for Hardening of the Arteries (Atherosclerosis). Heart disease is associated with high cholesterol, high blood pressure, increased platelet aggregation, and the hardening of blood vessels. Platelets stop bleeding by clotting blood vessel injuries. However, platelet aggregation also leads to blood clots, which increase the risk of heart disease. Limited evidence suggests that garlic may lower cholesterol, reduce blood pressure, relax hardened blood vessels, and prevent platelet aggregation in patients with heart disease. This is uncertain and large-scale studies are needed. S-allyl cysteine in aged garlic extract inhibits enzymes involved in cholesterol production. Garlic extract also increases the production and function of nitric oxide, which relaxes blood vessels and lowers blood pressure. Garlic also prevents platelets from binding to proteins (fibrinogen) that form blood clots and increase compounds (cAMP) that inhibit platelet formation

Garlic Improves Cholesterol Levels, Which May Lower the Risk of Heart Disease. Garlic can lower total and LDL cholesterol. For those with high cholesterol, garlic appears to reduce total and/or LDL cholesterol by about 10–15%. Looking at LDL (the “bad”) and HDL (the “good”) cholesterol specifically, garlic appears to lower LDL but has no reliable effect on HDL. High triglyceride levels are another known risk factor for heart disease, but garlic seems to have no significant effects on triglyceride levels.

Researchers at Ankara University investigated the effects of garlic extract supplementation on the blood lipid (fat) profile of patients with high blood cholesterol. Their study was published in the Journal of Nutritional Biochemistry. The study involved 23 volunteers, all with high cholesterol; 13 of them also had high blood pressure. They were divided into two groups:

-The high-cholesterol normotensive group (normal blood pressure ).

-The high-cholesterol hypertensive group (high blood pressure).

They took garlic extract supplements for 4 months and were regularly checked for blood lipid parameters, as well as kidney and liver function. At the end of the 4 months, the researchers concluded “…garlic extract supplementation improves blood lipid profile, strengthens blood antioxidant potential, and causes significant reductions in systolic and diastolic blood pressures. It also leads to a decrease in the level of oxidation product (MDA) in the blood samples, which demonstrates reduced oxidation reactions in the body.” In other words, the garlic extract supplements reduced high cholesterol levels, and also blood pressure in patients with hypertension. The scientists added that theirs was a small study – more work needs to be carried out.

Diallyl trisulfide, a component of garlic oil, helps protect the heart during cardiac surgery and after a heart attack, researchers at Emory University School of Medicine found. They also believe diallyl trisulfide could be used as a treatment for heart failure. Hydrogen sulfide gas has been shown to protect the heart from damage. However, it is a volatile compound and difficult to deliver as therapy. Because of this, the scientists decided to focus on diallyl trisulfide, a garlic oil component, as a safer way to deliver the benefits of hydrogen sulfide to the heart. In experiments using laboratory mice, the team found that, after a heart attack, the mice that had received diallyl sulfide had 61% less heart damage in the area at risk, compared with the untreated mice. In another study, published in the Journal of Agricultural and Food Chemistry, scientists found that garlic oil may help protect diabetes patients from cardiomyopathy. Cardiomyopathy is the leading cause of death among diabetes patients. It is a chronic disease of the myocardium (heart muscle), which is abnormally thickened, enlarged, and/or stiffened. The team fed diabetic laboratory rats either garlic oil or corn oil. Those fed garlic oils experienced significantly more changes associated with protection against heart damage, compared with the animals that were fed corn oil. The study authors wrote, “In conclusion, garlic oil possesses significant potential for protecting hearts from diabetes-induced cardiomyopathy.” Human studies will need to be performed to confirm the results of this study.

Possibly Effective for High Blood Fats (Hyperlipidemia). According to limited studies, garlic lowers total and low-density lipoprotein (LDL) cholesterol by inhibiting cholesterol synthesis in the liver in human and animal studies. Garlic lowered cholesterol by deactivating cholesterol-producing enzymes in 70 diabetic patients. However, the evidence about garlic’s cholesterol-lowering effect is mixed. According to the NIH, even if garlic does lower blood cholesterol, “the effect is small, and low-density lipoprotein (LDL) cholesterol (the so-called ‘bad’ cholesterol that’s linked to increased heart disease risk) may not be reduced at all.”

Possibly Effective for Blood Sugar Control in Diabetes. Diabetes is caused by genetics, obesity, high cholesterol, blood pressure, or blood glucose. Insulin resistance occurs when the body no longer responds to insulin, leading to increased blood sugar levels and a high risk of developing diabetes. According to some researchers, garlic might reduce insulin resistance, blood sugar, and cholesterol levels in patients with diabetes. Some clinical studies suggest that garlic might slightly lower pre-meal blood sugar levels, particularly if taken for at least 3 months in people with diabetes. More research is needed. Garlic reduced blood sugar levels in rats by decreasing the activity of enzymes (phosphatases and aminotransferases) involved in the transportation of glucose in the liver, a sugar that is the body’s main source of energy. Also, garlic may reduce insulin resistance by inhibiting an enzyme that breaks down drugs (CYP2E1), ultimately disrupting insulin function by increasing oxidative stress.

Possibly Effective for Certain Yeast Infections. Small clinical trials suggest that applying a gel with garlic (containing 0.6% ajoene) twice daily may improve the following yeast infections within a week:

-Ringworm (Tinea corporis)

-Jock itch (Tinea cruris)

-Athlete’s foot (Tinea pedis)

Possibly Effective for Repelling Ticks. Garlic seems to be a promising insect repellent, but just how well it works compared to standard synthetic repellents is still unknown. In one study, people who ate a lot of garlic (1200 mg daily) over 8 weeks seemed to have fewer tick bites, compared to placebo.

Garlic Contains Antioxidants That May Help Prevent Alzheimer’s Disease and Dementia. Oxidative damage from free radicals contributes to the aging process. Garlic contains antioxidants that support the body’s protective mechanisms against oxidative damage. High doses of garlic have been shown to increase antioxidant enzymes in humans, as well as significantly reduce oxidative stress in those with high blood pressure. The combined effects on reducing cholesterol and blood pressure, as well as the antioxidant properties, may reduce the risk of common brain diseases like Alzheimer’s disease and dementia.

Garlic May Help You Live Longer. The potential effects of garlic on longevity are basically impossible to prove in humans. But given the beneficial effects on important risk factors like blood pressure, it makes sense that garlic could help you live longer. The fact that it can fight infectious disease is also an important factor, because these are common causes of death, especially in the elderly or people with dysfunctional immune systems.

Athletic Performance Might Be Improved With Garlic Supplements. Garlic was one of the earliest “performance enhancing” substances. It was traditionally used in ancient cultures to reduce fatigue and enhance the work capacity of laborers. Most notably, it was given to Olympic athletes in ancient Greece. Rodent studies have shown that garlic helps with exercise performance, but very few human studies have been done. People with heart disease who took garlic oil for 6 weeks had a 12% reduction in peak heart rate and better exercise capacity. However, a study on nine competitive cyclists found no performance benefits. Other studies suggest that exercise-induced fatigue may be reduced with garlic.

Eating Garlic May Help Detoxify Heavy Metals in the Body. At high doses, the sulfur compounds in garlic have been shown to protect against organ damage from heavy metal toxicity. A four-week study in employees of a car battery plant (excessive exposure to lead) found that garlic reduced lead levels in the blood by 19%. It also reduced many clinical signs of toxicity, including headaches and blood pressure. Three doses of garlic each day even outperformed the drug D-penicillamine in reducing symptoms.

Garlic May Improve Bone Health. No human studies have measured the effects of garlic on bone loss. However, rodent studies have shown that it can minimize bone loss by increasing estrogen in females. One study in menopausal women found that a daily dose of dry garlic extract (equal to 2 grams of raw garlic) significantly decreased a marker of estrogen deficiency. This suggests that this supplement may have beneficial effects on bone health in women. Foods like garlic and onions may also have beneficial effects on osteoarthritis.

Women whose diets were rich in allium vegetables had lower levels of osteoarthritis, a team at King’s College London and the University of East Anglia, both in England, reported in the journal BMC Musculoskeletal Disorders. Examples of allium vegetables include garlic, leeks, shallots, onions, and rakkyo. The study authors said their findings not only highlighted the possible impact of diet on osteoarthritis outcomes but also demonstrated the potential for using compounds that exist in garlic to develop treatments for the condition. The long-term study, involving more than 1,000 healthy female twins, found that those whose dietary habits included plenty of fruit and vegetables, “particularly alliums such as garlic,” had fewer signs of early osteoarthritis in the hip joint.

Acts as a natural antibiotic. Garlic has significant antibacterial properties that help protect against certain infections. This is particularly important for strains resistant to antibiotics, including MRSA. Though it should not replace treatment by your physician, garlic can offer protective benefits as a supplement.

Diallyl sulfide, a compound in garlic, was 100 times more effective than two popular antibiotics in fighting the Campylobacter bacterium, according to a study published in the Journal of Antimicrobial Chemotherapy. The Campylobacter bacterium is one of the most common causes of intestinal infections. Senior author, Dr. Xiaonan Lu, from Washington State University, said, “This work is very exciting to me because it shows that this compound has the potential to reduce disease-causing bacteria in the environment and in our food supply.”

Garlic is one of the best-kept medicinal treasures of the past era - it has been used as an antibiotic to treat bacterial, fungal, and parasitic infections for the last 7,000 years. Studies suggest diluted garlic extract helps children with tapeworm infections. A garlic-based mouthwash may not sound like fresh, minty breath but a very small quantity of its extracts is sufficient to ward off cavity-causing bacteria.

Clears your skin. Because of its antibacterial properties, garlic can help reduce swelling and inflammation from acne. Although some people suggest using topically to treat skin conditions from acne to athlete’s foot, it is best to avoid placing garlic directly on the skin, as it can cause a rash, a burning sensation, and, in rare cases, blistering.

The invigorating properties of garlic protect the skin from the effect of free radicals and slow down the depletion of collagen which leads to loss of elasticity in aging skin. Applied topically, garlic does wonders to skin infected with fungal infections and provides relief from skin ailments like eczema. It is also an effective remedy for fungal infections like athlete’s foot and ringworms. All of us know about the wonders of onion for hair but its brother, garlic is no less of a hero for your thinning mane. Well, it's surprise time. Rubbing crushed garlic extract on your scalp or massaging it with garlic-infused oil is known to prevent and even reverse hair loss.

Preterm (premature) delivery. Microbial infections during pregnancy raise a woman’s risk of preterm delivery. Scientists at the Division of Epidemiology, Norwegian Institute of Public Health, studied what impact foods might have on antimicrobial infections and preterm delivery risk. The study and its findings were published in the Journal of Nutrition. Ronny Myhre and colleagues concentrated on the effects of Alliums and dried fruits, because a literature search had identified these two foods as showing the greatest promise for reducing preterm delivery risk. The team investigated the intake of dried fruit and Alliums among 18,888 women in the Norwegian Mother and Child Cohort, of whom 5 percent (950) underwent spontaneous PTD (preterm delivery). The study authors concluded, “Intake of food with antimicrobial and prebiotic compounds may be of importance to reduce the risk of spontaneous PTD. In particular, garlic was associated with an overall lower risk of spontaneous PTD.”

Alcohol-induced liver injury. Alcohol-induced liver injury is caused by the long-term over-consumption of alcoholic beverages. Scientists at the Institute of Toxicology, School of Public Health, Shandong University, China, wanted to determine whether diallyl disulfide (DADS), a garlic-derived organosulfur compound, might have protective effects against ethanol-induced oxidative stress. Their study was published in Biochimica et Biophysica Acta. The researchers concluded that DADS might help protect against ethanol-induced liver injury.

It’s good for your gut. Garlic functions as a prebiotic, food for beneficial bacteria in the gut tied to immunity and positive mood. Research has also shown that aged garlic extract positively improves the diversity of microbes in the gut, including an increase in the number of beneficial and immune-stimulating bacteria.

It contains cancer-fighting characteristics. Significant evidence suggests that garlic can play a role in the prevention of cancer and the slowing of its progression. “Garlic’s rich phytochemical content delivers its potential cholesterol-lowering and cancer-fighting characteristics,” says Bakko. Phytochemicals are chemical compounds found in plants that protect cells from damage that lead to cancer.

Possibly Effective for Prostate Cancer Prevention. Findings on the effects of dietary garlic intake on prostate cancer prevention have been mixed. A link between higher garlic intake (over 2 grams/day) and lower prostate cancer risk has been suggested in Chinese men. Also, early clinical studies suggest that garlic supplements may help prevent prostate cancer. S-allyl cysteine and SAMC inhibit prostate cancer cell growth by re-activating E-cadherin, a molecule that suppresses tumor invasion, in cancer patients. A low level of E-cadherin is associated with a high number of tumors and a poor prognosis in prostate cancer patients. Although classified as possibly effective for prostate cancer prevention based on the existing evidence, larger clinical trials are needed.

Doctors at the Department of Urology, China-Japan Friendship Hospital, Beijing, China, carried out a study evaluating the relationship between Allium vegetable consumption and prostate cancer risk. They gathered and analyzed published studies up to May 2013 and reported their findings in the Asian Pacific Journal of Cancer Prevention. The study authors concluded, “Allium vegetables, especially garlic intake, are related to a decreased risk of prostate cancer.” The team also commented that because there are not many relevant studies, further well-designed prospective studies should be carried out to confirm their findings.

Brain cancer. Organo-sulfur compounds found in garlic have been identified as effective in destroying the cells in glioblastomas, a type of deadly brain tumor. Scientists at the Medical University of South Carolina reported in the journal Cancer that three pure organo-sulfur compounds from garlic – DAS, DADS, and DATS – “demonstrated efficacy in eradicating brain cancer cells, but DATS proved to be the most effective.” Co-author, Ray Swapan, Ph.D., said “This research highlights the great promise of plant-originated compounds as a natural medicine for controlling the malignant growth of human brain tumor cells. More studies are needed in animal models of brain tumors before application of this therapeutic strategy to brain tumor patients.”

Lung cancer risk. People who ate raw garlic at least twice a week during the 7 year study period had a 44% lower risk of developing lung cancer, according to a study conducted at the Jiangsu Provincial Center for Disease Control and Prevention in China. The researchers, who published their study in the journal Cancer Prevention Research, carried out face-to-face interviews with 1,424 lung cancer patients and 4,543 healthy individuals. They were asked about their diet and lifestyle, including questions on smoking and how often they ate garlic. The study authors wrote: “Protective association between intake of raw garlic and lung cancer has been observed with a dose-response pattern, suggesting that garlic may potentially serve as a chemopreventive agent for lung cancer.”