I initially thought I knew it all but the more I dig into it, the more I found out...
Some facts on garlic
Dating back over 6,000 years, garlic is native to central Asia. It was already known during the Egyptian empire, and has been, since then, used throughout the centuries for both culinary and medicinal purposes.
Garlic is a species in the onion genus and its close relatives include, among others, onion, shallot, leek, and chive.
Nowadays, garlic health benefits are widely accepted also in the medical community and doctors around the globe recognize that many problems can be prevented and treated with a daily dose of garlic.
Modern science has shown that garlic is a powerful natural antibiotic, albeit a broad-spectrum rather than targeted one.
This is actually good news because it means that the bacteria in the body do not appear to evolve resistance to the garlic as they do to many modern pharmaceutical antibiotics. This means that its positive health benefits can continue over time rather than helping to breed antibiotic resistant.
In the tropics it is quite customary for people to apply a cut glove of garlic on cuts in order to avoid infections. It’s a bit painful but it works!
From a medical history standpoint, the antibacterial and antiviral properties of garlic are perhaps its most legendary feature.
This allium vegetable and its constituents have been studied not only for their benefits in controlling infection by bacteria and viruses, but also infection from other microbes including yeasts/fungi and worms.
Recent research has shown the ability of crushed fresh garlic to help prevent infection by the bacterium Pseudomonas aeruginosa in burn patients. Also of special interest has been the ability of garlic to help in the treatment of bacterial infections that are difficult to treat due to the presence of bacteria that have become resistant to prescription antibiotics. However, most of the research on garlic as an antibiotic has involved fresh garlic extracts or powdered garlic products rather than fresh garlic in whole food form.
Several research have also shown that garlic is a powerful antioxidant and a powerful cancer blocker.
In particular, a number of new studies on garlic that have recently appeared deal with garlic and cancer. One published in Journal of Biochemical and Molecular Toxicology cites diallyl disulfide (DADS) as the most prevalent oil-soluble sulfur compound in garlic, inhibiting cell proliferation in many cell lines. Scientists there examined DADS ability to kill cells in a process involving free radical production.
Diallyl disulfide is not the most potent compound found in garlic, but it has an advantage because it is the less volatile of the compounds. DADS does not degrade as quickly and its health benefits survive cooking. Garlic needs to be chopped or crushed to produce the these sulfides. If it is cooked whole, it loses most of its medicinal value and health benefits.
DADS is a potent booster of the immune system, and improves blood quality and circulation. It has been shown in studies to lower LDL cholesterols levels, and through this action may help keep the heart and cardiovascular system healthy.
Another recent study, reported in the Mutation Research, revealed the action through which garlic decreases genetic mutations and reduces the number of small and large papillary lung tumors.
Allicin is garlic's most potent compound
Allicin is the compound providing the largest range of garlic's health benefits. Allicin also does not occur in garlic cloves, but is produced when garlic is finely chopped or crushed. The finer the chopping and the more intense the crushing, the more allicin is produced and the stronger is the medicinal effect.
Allicin has both antibiotic and anti-fungal properties, and made garlic a favorite in folk medicine for treating skin infections such as athlete's foot. Allicin is potent stuff (so powerful that too much exposure to garlic can result in blistered skin.)
It should be noted that allicin starts to degrade immediately after it is produced, so a person seeking to reap its full medicinal benefits should use it immediately after crushing it. Cooking increases the degradation of allicin, and microwaving completely destroys allicin and eliminates any health benefits.
This means that in order to gain the optimal in medicinal effects, garlic should be crushed and added to food immediately before serving.
Effects on cardiovascular system
Most of the research on garlic and our cardiovascular system has been conducted on garlic powder, garlic oil, or aged garlic extracts rather than garlic in food form. But despite this research limitation, food studies on garlic show that garlic has important cardioprotective properties. Garlic is clearly able to lower our blood triglycerides and total cholesterol, even though this reduction can be moderate (5-15%).
But cholesterol and triglyceride reduction are by no means garlic's most compelling benefits when it comes to cardioprotection. Those top-level benefits clearly come in the form of blood cell and blood vessel protection from inflammatory and oxidative stress. Damage to blood vessel linings by highly reactive oxygen molecules is a key factor for increasing our risk of cardiovascular problems, including heart attack and atherosclerosis. Oxidative damage also leads to unwanted inflammation, and it is this combination of unwanted inflammation and oxidative stress that puts our blood vessels at risk of unwanted plaque formation and clogging. Garlic unique set of sulfur-containing compounds helps protect us against both possibilities—oxidative stress and unwanted inflammation.
The following provides a list of sulfur-containing garlic's constituents that help lower our risk of oxidative stress:
Equally impressive about garlic is its ability to lower blood pressure. Researchers have known for about 10 years that the allicin made from alliin in garlic blocks the activity of angiotensin II. A small piece of protein (peptide), angiotensin II helps our blood vessels contract. (When they contract, our blood is forced to pass through a smaller space, and the pressure is increased.) By blocking the activity of angiotensin II, allicin form garlic is able to help prevent unwanted contraction of our blood vessels and unwanted increases in blood pressure.
Garlic's vitamin B6 helps prevent heart disease via another mechanism: lowering levels of homocysteine. An intermediate product of an important cellular biochemical process called the methylation cycle, homocysteine can directly damage blood vessel walls.
The selenium in garlic can become an important part of our body's antioxidant system. A cofactor of glutathione peroxidase(one of the body's most important internally produced antioxidant enzymes), selenium also works with vitamin E in a number of vital antioxidant systems.
Garlic is rich not only in selenium, but also in another trace mineral, manganese, which also functions as a cofactor in a number of other important antioxidant defense enzymes, for example, superoxide dismutase. Studies have found that in adults deficient in manganese, the level of HDL (the "good form" of cholesterol) is decreased.
There's preliminary evidence (mostly from animal studies, and mostly based on garlic extracts rather than whole food garlic) that our our musculoskeletal system and respiratory system can also benefit from anti-inflammatory compounds in garlic. Both the diallyl sulfide (DAS) and thiacremonone in garlic have been shown to have anti-arthritic properties. And in the case of allergic airway inflammation, aged garlic extract has been show to improve inflammatory conditions (once again in animal studies).
Even garlic isn't a perfect. Apart from garlic breath there are other possible side effects, especially if used to excess. Use common sense and don't overdo it.
Raw garlic is very strong, so eating too much could produce problems, for example irritation of or even damage to the digestive tract.
There are a few people who are allergic to garlic. Symptoms of garlic allergy include skin rash, temperature and headaches. Also, garlic could potentially disrupt anti-coagulants, so it's best avoided before surgery. As with any medicine, always check with your doctor first and tell your doctor if you are using it.
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