Garlic (Allium sativum)

Garlic is an herb that is grown around the world. It is related to onion, leeks, and chives. It is thought that garlic is native to Siberia, but spread to other parts of the world over 5000 years ago.

Garlic is used for many conditions related to the heart and blood system. These conditions include high blood pressure, low blood pressure, high cholesterol, inherited high cholesterol, coronary heart disease, heart attack, reduced blood flow due to narrowed arteries, and "hardening of the arteries" (atherosclerosis).

Some people use garlic to prevent colon cancer, rectal cancer, stomach cancer, breast cancer, prostate cancer, multiple myeloma, and lung cancer. It is also used to treat prostate cancer and bladder cancer.

Garlic has been tried for treating an enlarged prostate (benign prostatic hyperplasia; BPH), cystic fibrosis, diabetes, osteoarthritis, hayfever (allergic rhinitis), traveler's diarrhea, high blood pressure late in pregnancy (pre-eclampsia), yeast infection, flu, and swine flu. It is also used to prevent tick bites, as a mosquito repellant, and for preventing the common cold, and treating and preventing bacterial and fungal infections.

Garlic is also used for earaches, chronic fatigue syndrome, menstrual disorders, abnormal cholesterol levels caused by HIV drugs, hepatitis, shortness of breath related to liver disease, stomach ulcers caused by H. pylori infection, exercise performance, exercise-induced muscle soreness, a condition that causes lumps in the breast tissue called fibrocystic breast disease, a skin condition called scleroderma, and lead toxicity.

Other uses include treatment of fever, coughs, headache, stomach ache, sinus congestion, gout, joint pain, hemorrhoids, asthma, bronchitis, shortness of breath, low blood sugar, snakebites, diarrhea and bloody diarrhea, tuberculosis, bloody urine, a serious nose and throat infection called diphtheria, whooping cough, tooth sensitivity, stomach inflammation (gastritis), scalp ringworm, and a sexually transmitted disease called vaginal trichomoniasis. It is also used for fighting stress and fatigue.

Some people apply garlic oil to their skin or nails to treat fungal infections, warts, and corns. It is also applied to the skin for hair loss and thrush.

Garlic is used in the vagina for yeast infections.

Garlic is injected into the body for chest pain.

In foods and beverages, fresh garlic, garlic powder, and garlic oil are used to add flavor.

How does it work?

Garlic produces a chemical called allicin. This is what seems to make garlic work for certain conditions. Allicin also makes garlic smell. Some products are made "odorless" by aging the garlic, but this process can also make the garlic less effective. It's a good idea to look for supplements that are coated (enteric coating) so they will dissolve in the intestine and not in the stomach.

Hardening of the arteries (atherosclerosis).
High cholesterol.
High blood pressure.
Tick bites.
Ringworm.
Jock itch.
Athlete's foot.
Hair loss (alopecia areata).
Chest pain (angina).
Benign prostatic hyperplasia (BPH).
Common cold.
Clogged arteries (coronary heart disease).
Corns.
Muscle soreness after exercise.
Exercise performance.
Lumpy breast tissue (fibrocystic breast disease).
Stomach inflammation (gastritis).
Hepatitis.
Shortness of breath and low oxygen levels associated with liver disease (hepatopulmonary syndrome).
Lead poisoning.
Thrush (oral candidiasis).
Mouth ulcers (oral mucositis).
Hardening and tightening of the skin and connective tissue (scleroderma).
Vaginal yeast infections.
Warts.
Weight loss.

By mouth

For hardening of the arteries: A 300 mg garlic powder tablet (Kwai, Lichtwer Pharma), taken as a single dose or three times daily for up to 4 years, has been used. Also, 150 mg of a specific garlic supplement (Allicor, INAT-Farma, Moscow, Russia) twice daily for 24 months has been used. Combination products containing garlic have also been used. A specific aged garlic extract supplement (Kyolic, Total Heart Health, Formula 108, Wakunga) containing 250 mg of aged garlic extract taken daily for 12 months, has been used. Also, a combination product containing 300 mg aged garlic extract, taken at a dose of four tablets daily for one year, has been used.

For colon cancer and rectal cancer: Capsules containing 2.4 mL of aged garlic extract taken daily for 12 months have been used.

For high cholesterol: A dose of 1000 mg to 7200 mg of a specific aged garlic extract (Kyolic, Wakanuga) has been used daily in divided doses for 4-6 months. A dose of 600 mg to 900 mg of a specific garlic powder tablet (Kwai, Lichtwer Pharma) has been taken daily in two or more divided doses for 6-16 weeks. Also, 300 mg of another specific garlic powder product (Garlex, Bosch Pharmaceuticals) taken twice daily for 12 weeks has been used. Also, 1200 mg of garlic powder plus 3 grams of fish oil daily for 4 weeks, or 500 mg of garlic oil plus 600 mg of fish oil daily for 60 days, has been used.

For high blood pressure: 300-1500 mg of garlic tablets taken in divided doses daily for 24 weeks has been used. 2400 mg of a specific garlic powder tablet (Kwai, Lichtwer Pharma) taken as a single dose or 600 mg daily for 12 weeks has been used. Capsules containing 960 mg to 7.2 grams of aged garlic extract, taken daily in up to three divided doses for up to 6 months, have been used. Specific products containing aged garlic extract include Kyolic (Garlic High Potency Everyday Formula 112, Wakunga/Wagner). 500 mg of garlic oil 500 mg plus 600 mg of fish oil daily for 60 days has been used.

For prostate cancer: 1 mg/kg of a water-soluble garlic extract, taken daily for one month, has been used.
For tick bites: Capsules containing 1200 mg of garlic taken daily for 8 weeks have been used.

By skin

For fungal skin infections (ringworm, jock itch, athlete's foot): garlic ingredient ajoene as a 0.4% cream, 0.6% gel, and 1% gel applied twice daily for one week has been used.

Garlic is SAFE for most people when taken by mouth appropriately. Garlic has been used safely in research for up to 7 years. When taken by mouth, garlic can cause bad breath, a burning sensation in the mouth or stomach, heartburn, gas, nausea, vomiting, body odor, and diarrhea. These side effects are often worse with raw garlic. Garlic may also increase the risk of bleeding. There have been reports of bleeding after surgery in people who have taken garlic. Asthma has been reported in people working with garlic, and other allergic reactions are possible.

Garlic products are SAFE when applied to the skin. Gels, pastes, and mouthwashes containing garlic have been used for up to 3 months. However, when applied to the skin, garlic might cause skin damage that is similar to a burn.

RAW garlic is POSSIBLY UNSAFE when applied to the skin. Raw garlic might cause severe skin irritation when it is applied to the skin.

Pregnancy and breast-feeding: Garlic is SAFE to use during pregnancy when taken in the amounts normally found in food. Garlic is POSSIBLY UNSAFE when used in medicinal amounts during pregnancy and when breast-feeding. There is not enough reliable information about the safety of applying garlic to the skin if you are pregnant or breast feeding. Stay on the safe side and avoid use.

Children: Garlic is POSSIBLY SAFE when taken by mouth and appropriately for a short-term in children. However, garlic is POSSIBLY UNSAFE when taken by mouth in large doses. Some sources suggest that high doses of garlic could be dangerous or even fatal to children. The reason for this warning is not known. There are no case reports available of significant adverse events or mortality in children associated with taking garlic by mouth. When applied to the skin, garlic might cause damage to the skin that is similar to a burn.

Bleeding disorder: Garlic, especially fresh garlic, might increase the risk of bleeding.

Stomach or digestion problems: Garlic can irritate the gastrointestinal (GI) tract. Use with caution if you have stomach or digestion problems.

Low blood pressure: Garlic can lower blood pressure. In theory, taking garlic might make blood pressure become too low in people with low blood pressure.

Surgery: Garlic might prolong bleeding and interfere with blood pressure. Stop taking garlic at least two weeks before a scheduled surgery.