Garlic

There are three varieties of the species Allium sativum L.: snake garlic (var. ophioscorodon), Peking garlic (var. pekinense) and the common garlic (var. sativum) known in this country. Common garlic is a perennial, herbaceous plant and grows to a height of 25 to 90 cm. The brownish-grey to gray-green, pointed leaves are flat, elongated, broad, grooved and rough at the edges. The round flower stalk bears a few-flowered pseudo-umbrellas and several brood bulbs. The flowers often remain in bud and do not produce seeds.

Originally native to Central Asia, the plant is now grown everywhere and used to flavor food. The mature, not yet dried sprouting onion is harvested, which is made up of an egg-shaped main bulb and 6 to 15 secondary bulbs (= cloves). Both are surrounded by a white, dry leaf sheath. Like all strong-smelling plants, garlic was once used to drive away demons (e.g. vampires).

History of garlic

Egypt was the land of garlic in ancient times, where it was considered a sacred plant. Herodotus famously reported that garlic was eaten by the workers building the pyramids. To supply them with garlic, radishes and onions, 1600 silver talents had to be spent on the construction of the pyramid of Cheops alone, a sum that only wealthy multi-millionaires could afford today. In Greece, garlic was said to give strength. But the gods didn't like it because it stank. As a result, garlic eaters were forbidden from visiting temples and the nobility no longer ate it. Since then, it has had the stigma of being unclean and was considered the food of poor people. Knowing its health-promoting effects, it was also considered an aphrodisiac. For the festival of Ceres, the goddess of fertility, the Romans made a love potion from garlic and coriander.

The FLORIDUS MACER states: "Consumed or applied as an ointment, allium cures stings and bites inflicted by snakes or scorpions, and when applied with honey, it also cures dog bites." And a little further on, there are instructions to "serve it with centaury to water addicts, because it dries the watery bodily fluids" and "that kidney patients should eat it boiled." Dioscorides confirms this and prescribes it mixed with honey against "the trembling / lichen / spotting / masen / the flowing head weight / the joyful and small scales of the head." In the Middle Ages, it was even used as a remedy for the plague, as it was a component of the four-predator or plague vinegar, acetum aromaticum, which also included rue and sage. Garlic was Theriaca rusticorum, the theriac of the common people. Theriac is a collective term for magically produced mixtures that were regarded as universal antidotes and life-rejuvenating elixirs. Von Perger explains why garlic was used for this purpose: "Because garlic turns black when it hangs in the air for a long time, it was believed to attract evil, and for this reason it was used to excrete the poison or as a preservative against it." The ancient Hebrews wore it around their necks as a talisman.

Hecate, the goddess of magic, was given a few cloves of garlic at a crossroads as a night-time meal. Garlic played and still plays an important role in folk medicine and superstition throughout Europe. In people's imagination, its antibacterial effect makes it magical. Legends attribute to it an incantatory effect against witches and devils. Its deterrent, almost paralyzing effect on vampires is legendary. Sailors took plenty of garlic with them on their voyages. It helped against bacteria when the water in the boilers rotted and became undrinkable. It was also used in the warm countries of the Orient, where the wells and cisterns did not always provide the best quality drinking water.

Today's importance and use

The smell, taste and medicinal effect of garlic are very characteristic. As the smell is released through the sweat glands, everyone recognizes the garlic eater immediately, unless you have eaten it yourself. Because garlic tastes good and is healthy, it has many friends, but because it stinks, it also has just as many enemies. Drinking plenty of milk or red wine or chewing the spicy leaves of other herbs such as rue is said to help combat the smell. The essential oil of garlic contains allicin, from which its steam-volatile conversion products allicin and ajoene are formed when the cells are destroyed. Research has shown that allicin and other components of the essential oil have a strong antibacterial effect, meaning that garlic also helps with serious infections such as dysentery. Before the discovery of antibiotics, garlic was used to treat wounds during the First World War.

Its expectorant properties make it a remedy for respiratory infections, colds, flu, ear infections and catarrh. It soothes the stomach and intestines and eliminates intestinal parasites. Garlic has a blood-thinning effect, lowers blood pressure and cholesterol levels, which counteracts the risk of a stroke. As it lowers blood sugar levels, it can also be added to the diet of people with adult-onset diabetes. The therapeutic dosage for this dietary measure is 4 g of fresh garlic a day. Various preparations are used, which differ in their production and are therefore not necessarily comparable in their effect. Preparations with a standardized content of alliin and allicin have been best studied.

Potential health benefits of garlic and their scientific basis

It is not without reason that garlic was used in ancient times primarily for its medicinal and health-promoting properties (1). Its medicinal use has been documented by many ancient civilizations including the Egyptians, Babylonians, ancient Greeks, Romans and Chinese (2). Today, scientists know that most of the health benefits of garlic can be attributed to sulfur compounds that are produced when garlic is chopped, crushed or chewed. Probably the best known of these compounds is the aforementioned allicin - an unstable compound that is only briefly present in fresh garlic when it has been cut or crushed (3).

Other compounds that may play a role from a health perspective include diallyl disulfide and S-allyl cysteine (4).The sulfur compounds contained in garlic enter the body via the digestive tract and are then transported throughout the body, where they exert their biological effects. In the following sections, we will take a closer look at some of the potential health benefits and the scientific data supporting these benefits.

Garlic can fight diseases including the common cold

Garlic supplements are known to boost the function of the immune system. A large-scale 12-week study found that daily supplementation with garlic reduced the risk of catching a cold by 63% compared to a placebo (6). The average duration of cold symptoms was 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 of illness with a cold or flu by 61% (7). However, another controlled study concluded that the scientific evidence is insufficient and further research is needed (8). Despite the lack of hard evidence, including garlic in your diet may be worth a try if you frequently suffer from colds.

Summary: Garlic supplements may help protect against or reduce the severity of infectious diseases such as the common cold and flu.

The active ingredients contained in garlic can lower blood pressure

Cardiovascular diseases such as heart attacks and strokes are among the most common causes of death worldwide. High blood pressure is one of the most important factors contributing to these diseases. Human studies have found that garlic supplements have a significant effect on reducing blood pressure in people suffering from high blood pressure (9, 10, 11). In one study, 500 to 1,500 mg of an aged garlic extract was as effective as the drug atenolol in reducing blood pressure over a 24-week period (12). Supplement dosages need to be quite high to achieve the desired effect. The required amount corresponds to about four cloves of garlic per day.

Summary: High doses of garlic appear to improve blood pressure in people with high blood pressure. In some cases, supplements may be as effective as regular medication.

Garlic improves cholesterol levels, which could reduce the risk of heart disease

Garlic can lower total cholesterol levels and LDL cholesterol levels. In people who suffer from high cholesterol levels, garlic supplements appear to lower total and/or LDL cholesterol levels by 10 to 15% (13, 14, 15). When LDL ("bad" cholesterol) and HDL ("good" cholesterol) levels are considered separately, garlic appears to specifically lower LDL cholesterol levels and have no effect on HDL cholesterol levels (9, 10, 16, 17, 18). High triglyceride levels are another known risk factor for heart disease, but garlic does not appear to have a significant effect on triglyceride levels (13, 15).

Summary: Garlic supplements appear to lower total cholesterol levels and LDL cholesterol levels, which seems to be particularly the case in people who have high cholesterol levels. HDL cholesterol levels and triglyceride levels do not appear to be affected by garlic.

Garlic contains antioxidants that may help prevent Alzheimer's and dementia

Oxidative damage caused by free radicals contributes to the ageing process. Garlic contains antioxidants that support the body's own mechanisms that protect against oxidative damage (19). High doses of garlic supplements have been shown to increase levels of antioxidant enzymes in humans and can significantly reduce oxidative stress in people suffering from high blood pressure (7, 9, 20). The combined effect of lowering cholesterol levels and blood pressure, as well as its antioxidant properties, could reduce the risk of common brain diseases such as Alzheimer's and dementia (21, 22).

Summary: Garlic contains antioxidants that may protect cells from damage and aging. Garlic may also reduce the risk of Alzheimer's disease and dementia.

Garlic could help you live longer

It is essentially impossible to prove the potential effects of garlic on longevity in humans. However, considering the effects of garlic on important risk factors such as blood pressure, it makes sense that garlic could prolong life. The fact that garlic is able to fight infectious diseases is another important factor, as such diseases are a common cause of death, especially in the elderly and those with compromised immune system function.

Summary: Garlic has well-established beneficial effects on chronic diseases, so it makes sense that it could also help prolong life.

Garlic could boost athletic performance

Garlic was one of the first performance-enhancing substances. It was traditionally used in ancient cultures to reduce fatigue and increase the working capacity of physically active people. Most notably, it was administered to Olympic athletes in ancient Greece (1). Research carried out on rodents shows that garlic can increase exercise performance, but unfortunately there are very few human studies on the subject to date.

In humans suffering from heart disease who took garlic oil over a 6-week period, a reduction in maximum heart rate and improved exercise capacity was observed (23). However, a study conducted with nine competitive cyclists did not show any benefits in terms of performance (24). Other studies suggest that exercise-induced fatigue could be reduced by garlic (2).

Summary: Garlic could improve physical performance in both animals and humans with heart disease. Benefits for healthy humans have not yet been conclusively demonstrated.

Garlic could help detoxify the body

It has been shown that high doses of the sulphur compounds contained in garlic can protect against organ damage caused by heavy metal poisoning. A four-week study of workers at a battery company (who were exposed to excessive amounts of lead) found that garlic reduced blood lead levels by 19%. It also reduced many clinical signs of toxicity including headaches and blood pressure (25). Three doses of garlic per day even outperformed the drug D-penicillamine in reducing symptoms.

Summary: Garlic has been shown to significantly reduce lead toxicity and related symptoms.

Garlic could improve bone health

There are no human studies to date that have directly examined the effects of garlic on bone loss. However, studies conducted with rodents show that garlic can minimize bone loss in women by increasing estrogen levels (26, 27, 28, 29). A study conducted in menopausal women found that a daily dose of a dry garlic extract (equivalent to about 2 grams of raw garlic) significantly reduced markers of estrogen deficiency (30). This suggests that garlic may have beneficial effects on bone health in women. Foods such as garlic and onions may also have beneficial effects on osteoarthritis (31).

Summary: Garlic appears to have some benefits for bone health by increasing estrogen levels in women, but more studies are needed to make a definitive statement.

Garlic is highly nutritious and low in calories

Calorie for calorie, garlic is highly nutritious. A 30 gram serving of garlic provides (5):

Manganese: 23% of the daily requirement
Vitamin B6: 17% of the daily requirement
Vitamin C: 15% of the daily requirement
Selenium: 6% of the daily requirement
Dietary fiber: 0.6 grams
Useful amounts of calcium, copper, potassium, phosphorus, iron and vitamin B1
42 kcal, 1.8 grams of protein and 9 grams of carbohydrates

It's easy to incorporate garlic into your diet and it tastes absolutely delicious Even though this doesn't fall under the category of health benefits, it's important because it makes it easy (and delicious) to incorporate garlic into your daily diet. Garlic is a great addition to most savory dishes, especially soups and sauces. The intense flavor of garlic can add that certain something to otherwise bland recipes. Garlic is available in various forms, ranging from whole garlic cloves to garlic cream, powder and supplements such as garlic extracts and garlic oil.

However, it should be kept in mind that garlic also has certain disadvantages, including the smell of the breath. There are also some people who are allergic to garlic. If you suffer from a blood clotting disorder or are taking blood-thinning medication, you should discuss any increase in your garlic consumption with your doctor in advance. A common way to enjoy garlic is to squeeze a few cloves of fresh garlic with a garlic press and mix the liquid with extra virgin olive oil and a little salt, which makes an extremely healthy and very tasty dressing.

Safety and side effects

Garlic is probably safe and harmless for most people when taken orally. Garlic can cause bad breath, heartburn, bloating, nausea, vomiting, bad 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 ingested garlic. There have been reported cases of asthma in people working with garlic and other allergic reactions are also possible. When used on the skin, garlic may not be safe and harmless. Use as a thick paste or poultice may cause skin damage similar to burns.

Precautions and warnings

Pregnancy and lactation: Garlic is probably safe when taken in normal amounts during pregnancy and lactation. However, when used in higher medicinal amounts, garlic may not be safe and safe for pregnant and breastfeeding women. There is insufficient reliable information on the safety and safety of using garlic on the skin during pregnancy and breastfeeding.

Children: Garlic may be safe for children when taken orally in reasonable amounts over a short period of time. However, oral ingestion in large amounts may not be safe and harmless. Some sources suggest that high doses of garlic may be dangerous and even fatal for children, although the reason for this warning is not known. There are no case reports of significant side effects or deaths in children associated with oral ingestion of garlic.

Blood clotting disorders: Garlic and especially fresh garlic could increase bleeding.

Stomach or digestive problems: Garlic can irritate the digestive tract. You should therefore use garlic with caution if you suffer from stomach or digestive problems.

Operations: Garlic could prolong bleeding. For this reason, you should stop taking garlic 2 weeks before an operation.

Interactions

Garlic should not be used in conjunction with the following medications:

Medications used for AIDS/HIV. (Non-nucleoside reverse transcriptase inhibitors (NNRTIs))

The body breaks down drugs used to treat AIDS/HIV in order to excrete them. Garlic may speed up the rate at which the body breaks down these drugs. Taking garlic in combination with some drugs used to treat AIDS/HIV could reduce the effectiveness of these drugs.

Care should be taken when combining garlic with the following medications:

Hormonal contraceptives (birth control pills):

Some birth control pills contain estrogen. The body breaks down the oestrogen contained in these contraceptive pills in order to be able to excrete it. Garlic may speed up the rate at which the body breaks down oestrogen. Taking garlic in combination with birth control pills could reduce the effectiveness of these medications. For this reason, additional contraceptive measures such as condoms should be used while taking garlic.

Drugs that are broken down by the liver (cytochrome P450 2E1 (CYP2E1) substrates)

Some drugs are broken down by the liver. Garlic can reduce the rate at which the liver breaks down certain drugs. Taking garlic in combination with medications that are broken down by the liver can increase the effects and side effects of some medications. For this reason, you should consult your doctor before taking garlic if you are taking medication that is broken down by the liver.

Drugs that are broken down by the liver (cytochrome P450 3A4 (CYP3A4) substrates)

Some drugs are broken down by the liver. Garlic may accelerate the rate at which the liver breaks down certain drugs. Taking garlic in conjunction with medications that are broken down by the liver may reduce the effects of some medications. For this reason, you should consult your doctor before taking garlic if you are taking medication that is broken down by the liver.

Medication that slows down blood clotting

Garlic could slow down blood clotting. Taking garlic in conjunction with medications that also slow down blood clotting could increase the risk of bleeding and the tendency to bruise. Some medications that can slow blood clotting include aspirin, diclofenac (Voltaren), ibuprofen, naproxen and others.

Conclusion

Humans have believed in the medicinal properties of garlic for thousands of years and modern science has now proven them.