Garlic (Allium sativum) isn't only a culinary herb and a vampire deterrent, but has for centuries been used as a herbal remedy.
Although preliminary research indicates that the herb has many possible benefits, the research remains inconclusive. So, no firm recommendations can be made as yet.
However, it's worth noting that numerous studies in humans have reported small reductions in total blood cholesterol and LDL ("bad") cholesterol over short periods of time (4 to 12 weeks). So, it's safe to say that garlic has a positive effect on cholesterol.
Stimulates immune system
Reduces skin and chest infections
Reduces blood clotting
Antibiotic and antidiabetic
Lowers blood pressure
Expectorant (dissolves mucus)
How does it work?
The active ingredients in garlic include allin and allicin. Allin gives garlic its characteristic taste and the sulphate, allicin, gives garlic its infamous odour. Allicin is responsible for the cholesterol-lowering effects of garlic.
Preliminary studies have found that garlic may help prevent cancer as it stimulates the immune system and disturbs the growth of malignant cells.
It has been proposed that garlic can be used as an adjunctive treatment to boost the immune system of cancer patients and that it can also prevent side effects from chemo- and radiotherapy.
Preliminary research shows that garlic may help treat chest infections. Taken with conventional antibiotics, it's believed that garlic supports their healing action and prevents unwanted side-effects.
By thinning the blood, garlic may help reduce the risk of circulatory problems, strokes, thromboses and heart disease, although this has not been conclusively proven. It also seems that garlic may help to dilate peripheral blood vessels, which, in turn, lowers blood pressure.
Animal studies have shown that garlic may help regulate blood sugar levels and may therefore help with late-onset diabetes. However, sudies in humans are needed to confirm these possible benefits.
Garlic may also be used to treat digestive infections, such as gastroenteritis and dysentery. The herb may also help to eliminate intestinal parasites, although this hasn't been conclusively proven.
Some studies have shown that rubbing fresh cloves directly onto the skin may help to treat acne and minor bacterial and fungal infections. But take care: garlic may cause a rash in some people.
Have 3-4g of freshly crushed garlic a day (this amounts to roughly one large clove) to lower cholesterol.
Pearls are supplements that contain garlic oil and can be taken to increase resistance to infection. Take 8mg daily.
Take four garlic tablets a day for high blood pressure and bronchitis. Make sure that tablets are standardised to contain at least 1.3% allicin.
Possible side effects
Possible side effects include stomach upset, intestinal problems, heartburn, bad breath and body odour. The last two side effects can be disguised by taking parsley with the garlic.
Are there any potentially dangerous herb-drug interactions?
Do not take garlic if you are on anticoagulant (blood-thinning) medications, such as warfarin and heparin, because it may cause excessive bleeding. Also avoid garlic if you take aspirin regularly.
Garlic may also decrease the effectiveness of immunosuppressants and HIV protease inhibitors.
Garlic may lower your blood sugar levels, decreasing your need for insulin. Before taking garlic and insulin together, consult your doctor and then monitor your blood sugar carefully and report any changes to your doctor.
Stop using garlic at least seven days before any surgery.
Do not use while breastfeeding.
Seek the advice of a medical professional before giving it as a medicine to children under 12.
(Image: Donovan Govan)
- (updated by Birgit Ottermann, Health24, April 2010)