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Quest Vitamins LTD,
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Aston Science Park,
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Registered in England No. 2530437

Garlic (Allium sativum)


Garlic has been used since ancient times for the treatment of many ailments, including parasites, respiratory problems, poor digestion, and low energy. The use of garlic has been mentioned in the Bible and the Talmud, by Hippocrates, Galen, Pliny the Elder, and Dioscorides. It has been used in China since A.D. 510.

Intact raw garlic cells contain alliin (an amino acid) and alliinase (an enzyme). When garlic is cut or crushed, alliin and alliinase immediately react together to produce the pungent substance allicin. Allicin has strong cytocidal (cell-killing) effects and kills all sorts of cells including pathogenic bacteria.

If crushed garlic is left to stand even for a short time, the allicin quickly disappears, because it is a highly unstable compound.


Aged Garlic Extract takes up to 20 months to produce through a cold aging process that creates a cascade of compounds which are stable and efficacious.

In addition to oil soluble compounds, Aged Garlic Extract also contains water-soluble compounds which will not be found in garlic oils or products produced using heat distillation.

Cold-ageing involves taking the highest quality organically-grown garlic, slicing it without acid or heat, and placing it in large stainless steel tanks to be left for twenty months.

During this cold-ageing period, allicin is converted to extremely valuable compounds that do not naturally occur with traditional/commercial processing methods.

Finally the garlic is extracted to harvest mainly water - and some oil-soluble compounds. An extra bonus is that the end product is completely odourless.

Differences in garlic -
Fresh raw garlic in excessive amounts can be irritating to the mouth and digestive tract. Fresh cooked garlic contains some beneficial compounds but also products from the chemical breakdown that can cause an odour. Cooked garlic can be less irritating to the mouth and digestive tract than raw garlic.

Differences in garlic product -
Garlic oil
- Made from garlic which has been distilled at high temperatures to extract the oil, which is mixed with vegetable or soya oil and made into capsules; or mixed with tabletting agents and made into tablets. The volatile compounds can be odorous. Rich in oil-soluble compounds.
Macerated garlic
- Mashed garlic infused with vegetable oil, which then takes up the oil-soluble compounds from the garlic. Can be odorous.
Dried garlic powder
- Sliced or crushed garlic is dried and may be made into tablets; or combined with vegetable oil and made into capsules. It contains oil and water-soluble
compounds. Can be odorous.
Aged garlic extract
- Organically grown garlic is harvested, minced and left in stainless steel tanks to age for 20 months. This process is known as cold Aging bio-conversion. Yields valuable water and oil-soluble compounds, especially S-allyl cysteine and S-allyl mercaptocysteine. This results in a naturally odourless garlic product with no toxic side effects.


Very many research papers have demonstrated the therapeutic benefits of cold-aged garlic - normally at levels of around 1000 mg per day. Lower intakes (such as 100mg, 300mg, 600mg) are to be used for maintenance of general good health, rather than tackling existing ailments.


When taking supplements it is important to know that they are going to have an effect beneficial to health. It is also reassuring to know a timescale in which they are going to work.

Microcirculation Impaired microcirculation can lead to
conditions such as Raynauds disease which cause cold hands and feet. This sensation can be quite uncomfortable and a quick treatment is always beneficial. AGE has been shown to improve microcirculation in as little as 90 minutes.

Glutathione levels Glutathione is an antioxidant enzyme
naturally found in the liver. Without this enzyme our detox systems would not function efficiently and toxins will be allowed to accumulate in body tissues and cause damage. AGE has been shown to boost glutathione levels in as little as 3 hours.

Blood Pressure Increased blood pressure (hypertension),
either caused by stress or poor blood biochemistry, can often result in a heart attack. If hypertension is diagnosed, it is prudent for it to be reduced as quickly as possible. AGE garlic has been shown to reduce blood pressure within 3 days.

Carcinogen binding Carcinogens, or cancer causing molecules, are highly undesirable and an increased circulating level will cause cellular damage and may lead to cancer. For those working/living in highly polluted areas, reducing this risk is vital. AGE can bind, and therefore eliminate, carcinogens within 3 days.

NK Cells NK (Natural Killer) cells are vital for our immune
response to pathogenic bacteria and it is important that these are working efficiently. During the winter months, having a healthy immune system may help prevent bacterial infections. AGE can increase NK cell efficiency within 3 weeks.

Platelet Aggregation Unwanted platelet aggregation can
lead to serious consequences such as deep vein thrombosis. Blood thinning therapies help to prevent platelet aggregation and keep the circulatory system in a healthy state. AGE can help thin the blood within 8 weeks.

Cholesterol High blood cholesterol levels are associated
with an increased risk of heart disease. LDL cholesterol in particular is responsible for these conditions. Lowering LDL and raising HDL is a desirable outcome of any medication. AGE can achieve this within 6 months.


Heart Health:
Cold-aged garlic can help to decrease total and LDL cholesterol, whilst HDL cholesterol remains unaffected (1). At first total cholesterol rises as it is mobilised from deposits in the blood vessels, but later it falls to below the original level. Garlic is believed to lower cholesterol levels by slowing its synthesis by the liver. Garlic may also lower triglyceride levels, slow blood coagulation (2), as well as prevent platelets from aggregating. It has mild antihypertensive properties (3).

Protection Against Free Radicals and Oxidation:
Raw garlic is actually an oxidant rather than an antioxidant. However the cold-ageing process reverses this and turns garlic into a strong antioxidant (4). Studies have shown that regular garlic consumption reduces the risk of oesophageal, stomach, and colon cancer (5). Garlic may reduce the formation of carcinogenic compounds. Studies also show that garlic may inhibit cancer growth, especially the growth of breast and Skin tumours.

Immune System:
Aged garlic has been shown to boost the activity of the bodys natural killer cells and many other aspects of the Immune System (6).

Aged garlic can increase the speed of clearance of Candida albicans cells from the body (7). Candida albicans is a yeast organism that can over-grow in the digestive tract causing digestive upset, Bloating, Thrush etc). Garlic may be beneficial to those who experience recurrent yeast infections.

Digestive Health:

Matsuura et al. (1997) found that Aged Garlic Extract enhances the growth of Lactobacillus acidophilus and Bifidobacterium bifidum, friendly intestinal bacteria, whereas other forms of garlic inhibited the growth of Bifidobacterium bifidum. B. bifidum and L. acidophilus produce both acid and anti-bacterial factors and have demonstrated an ability to decrease the growth of pathogens and their production of
toxic and cancer-causing compounds in the intestinal tract(8).

Respiratory Problems:
Aged garlic is suitable for use in catarrhal, respiratory or bronchial conditions.

Heavy Metals:
Aged Garlic Extract has been shown to protect red blood cells damage caused by heavy metals. Lau (1989) added various heavy metals (copper, mercury, aluminum and lead) to two sets of blood samples and to one set he also added Aged Garlic Extract. The heavy metals ruptured the red blood cells in each of the samples except for the cells to which Aged Garlic Extract had been added. This experiment clearly demonstrated a protective effect from the Aged Garlic Extract. (9).

Anti-Alzheimers Effect

SAC, one of the organosulphur compounds in aged garlic extract, has been shown to possess various biological effects, including neurotrophic activity. This study characterises the neuronal death induced by AÃÆ'ƒÆâ€â•ÃƒÆ'â€Â¦ÃƒÆ’‚¸, 4-hydroxynonenal (product of lipid peroxidation), tunicamycin antibiotic, and trophic factor deprivation, and investigates how SAC could prevent this effect. Results of this study indicate that SAC could protect against the neuronal cell death that is triggered by endoplasmic reticulum dysfunction in the hippocampus. (10)

Review article of the neurotrophic effect of AGE based upon preclinical studies. AGE has been shown to possess neurotrophic effects and protect brain or reduce dementia in the Alzheimer model. SAC and other constituents may be active compounds in AGE. (11)

Evidence suggests that risk factors for cardiovascular disease,
such as high cholesterol, hypertension, high homocysteine, and inflammation, increases the risk of dementia, including its most common form, Alzheimers disease (AD). Clinical studies have shown that Aged Garlic Extract (AGE) may help to prevent cardiovascular and cerebrovascular diseases and lower the risk of dementia and AD by inhibiting cholesterol, LDL oxidation, platelet aggregation, arterial plaque formation, decreasing homocysteine, lowering blood pressure, increasing microcirculation, protecting nerve cells. (12)

Anti-Depression Effect - Improved Serotonin Level

Fillion (1994), from the Institut Pasteur in France, found that Aged Garlic Extract may affect serotonin release in the brain. Serotonin has a series of effects on the body. It is involved in the regulation of sleep, body temperature, learning and memory, the release of stomach fluids and the immune system. It is also involved in cell growth, pain, feeding and sexual behaviour and adaptation to stress. Serotonin maintains homeostasis or balance in the brain.

When the serotonin system is faulty it results in anxiety, depression, aggressivity, panic obsessive compulsive disorder, schizophrenia, suicidal behaviour, autism, and possibly neurodegenerative disorders, migraines, Multiple Sclerosis and alcoholism. In cases of impulsivity, depression and such pathologies, the serotonergic(5HT) system is in deficit.

Antidepressants are often given in an attempt to boost the serotonin system. MAO (monoamine oxidase) inhibitors, for example, block the enzyme that degrades serotonin. Other antidepressants attempt to make
more serotonin available.

The serotonergic system exerts its effects on assorted neurotransmitters in the central nervous system via a number of different receptors (sort of bridges). (13)

Interaction with various receptors controls the release of serotonin. Fillion reported that Aged Garlic Extract may modulate receptors which bind to serotonin (inhibiting its release), thus making more serotonin available. By making more serotonin available, Aged Garlic Extract may potentially help to alleviate various pathologies resulting from its deficiency (e.g. depression, panic obsessive compulsive disorder, schizophrenia) as well as enhance systems, such as the immune system. (14)


Aged garlic has been extensively toxicity tested, and no amount of it seems to cause side effects. However, normal garlic may cause Heartburn and flatulence in some sensitive individuals.

The safety of any nutritional supplement is vital as they are designed to be used everyday. Aged garlic has an exemplary safety record and may be used by children and during pregnancy without any complications.

Aged garlic has been extensively toxicity tested, and no amount of it seems to cause side effects.

AGE is safe to take during pregnancy and breast feeding.

AGE may block the breakdown of chlorzoxazone (for the treatment of painful muscle conditions).

Dipyridamole is a drug preventing platelet clumping and AGE should be avoided with this medication.

AGE may dangerously enhance the effects of ticlopidine (a platelet inhibiting drug).


Aged garlic extract has no known drug interactions or contra-indications. However, this does not apply to all garlic preparations.

Garlic may interact with alkaloids, colchicine, dopamine receptor agonists, coumarin anticoagulants, and anorectic drugs (fenfluramine).

Avoid use with methotrimeprzine, a CNS depressant analgesic, and antituberculous drugs.

Sedatives, hypnotics, and beta-adrenergic blocking agents may inhibit garlics anti-inflammatory activity.

Coumadin (Warfarin)

Safety of intake of Aged Garlic Extract with coumadin has become a question since both show bloodthinning properties. A double-blind, placebo-controlled clinical trial by Rozenfeld et al. (1999) suggests that there is no toxic synergism between these substances and that Aged Garlic Extract is safe in conjunction with Coumadin®. (15)

No evidence of increased hemorrhage was observed in a clinical study with deep vein thrombosis patients on oral anticoagulation (Coumadin) therapy who were administered 5 ml of Aged Garlic Extract twice a day for 12 weeks. Aged Garlic Extract is relatively safe and poses no serious hemorrhagic risk for patients on oral anticoagulation
(Coumadin) therapy with close monitoring. (16, 17)

Aged garlic extract (AGE) was administered at a dose of 5 ml twice a day for 12 weeks in a double-blind, randomised, placebo-controlled pilot study. There was no evidence of increased hemorrhage in either the placebo or the AGE group. (18)


Except for a slight increase in sulphate conjugation, Gwilt et al.
(1994) found that Aged Garlic Extract did not affect the metabolism or efficacy of acetaminophen. (19)


Aged Garlic Extract - The Synergistic Nature of Garlic

Compounds in garlic work synergistically to produce various effects, but, because of garlics chemical complexity, processing methods yield preparations with differing efficacy and safety.

Although thiosulfinates such as allicin have been long misunderstood to be active compounds due to their characteristic odor, it is not necessary for garlic preparations to contain such odorous compounds to be effective, and they decompose and disappear during any processing. Garlic exhibits hypolipidemic, antiplatelet, and procirculatory effects. It prevents cold and flu symptoms through immune enhancement and demonstrates anticancer and chemopreventive activities. In addition, aged garlic extract possesses hepatoprotective, neuroprotective, antioxidative activities, whereas other preparations may stimulate oxidation.

Additional effects may be caused by S-allylcysteine, S-allyl mercaptocysteine), saponins, Nalpha-fructosyl arginine, and other substances formed during a long-term extraction process. Although not all of active ingredients of garlic are known, and allicin-like transient components are not directly active, ample research suggests that an allicin-free garlic preparation that is standardized with a bioavailable component such as S-allylcysteine, is active and various effects of garlic may be attributed to it. Furthermore, various chemical constituents in garlic products, including nonsulfur compounds such as saponins, may contribute to the essential biological activities of garlic.

J Nutr. 2006 Mar;136(3 Suppl):716S-725S.

Garlics Active Principles
One recent study indicated that S-allyl-cysteine (SAC) is one of the water soluble compounds in garlic derived from glutamyl peptides that increases during extraction. SAC is utilized to standardize AGE. SAC is contended to be the only compliance marker compound for clinical studies involving garlic consumption. Since SAC is present in garlic preparations has many biological effects and is confirmed to be available, it can be considered one of the active principles in garlic preparations.

Phytomed. 7(2):51 2000

Aged garlic extract ameliorates physical fatigue

Aged garlic extract (AGE) has recently received attention as a potent anti-fatigue agent. The principal aim of this study was to elucidate the mechanism responsible for the ameliorating effect of AGE on physical fatigue caused by repeated endurance exercise. The results indicate that AGE may facilitate the turnover of aerobic glucose metabolism, attenuate oxidative stress, and promote oxygen supply based on vasodilation, suggesting that AGE ameliorates the various impairments associated with physical fatigue.

Biol Pharm Bull. 2006 May;29(5):962-6.

Aged garlic extract inhibits angiogenesis and proliferation of colorectal carcinoma cells

Because colorectal cancer is likely to develop in many people at some point during their lives, prevention has become a high priority. Diet and nutrition play an important role during the multistep colon carcinogenic process. Garlic has been traditionally used as a spice and is well known for its medicinal properties; several studies have indicated its pharmacologic functions, including its anticarcinogenic properties.

This study investigated the effect of aged garlic extract (AGE) on the growth of colorectal cancer cells and their angiogenesis, which are important microenvironmental factors in carcinogenesis. AGE suppressed the proliferation of 3 different colorectal cancer cell lines. The action of AGE appears to be dependent on the type of cancer cell. On the other hand, AGE enhanced the adhesion of endothelial cells to collagen and fibronectin and suppressed cell motility and invasion. AGE also inhibited the proliferation and tube formation of endothelial cells potently. These results suggest that AGE could prevent tumor formation by inhibiting angiogenesis through the suppression of endothelial cell motility, proliferation, and tube formation.

AGE would be a good chemopreventive agent for colorectal cancer because of its antiproliferative action on colorectal carcinoma cells and inhibitory activity on angiogenesis.

J Nutr. 2006 Mar;136(3 Suppl):842S-846S.

Garlic reduces dementia and heart-disease risk

Risk factors for cardiovascular disease, including high cholesterol, high homocysteine, hypertension and inflammation, increase the risk of dementia, including its most common form, Alzheimers disease (AD). High cholesterol is also associated with elevated beta-amyloid (Abeta), the hallmark of AD. Oxidative damage is a major factor in cardiovascular disease and dementia, diseases whose risk increases with age. Garlic, extracted and aged to form antioxidant-rich aged garlic extract (AGE or Kyolic), may help reduce the risk of these diseases.

AGE scavenges oxidants, increases superoxide dismutase, catalase, glutathione peroxidase, and glutathione levels, and inhibits lipid peroxidation and inflammatory prostaglandins. AGE reduces cholesterol synthesis by inhibiting 3-hydroxy-3-methylglutaryl-CoA reductase and is additive with statins in its action. Inhibition of cholesterol, LDL oxidation, and platelet aggregation by AGE, inhibits arterial plaque formation; AGE decreases homocysteine, lowers blood pressure, and increases microcirculation, which is important in diabetes, where microvascular changes increase heart disease and dementia risks. AGE also may help prevent cognitive decline by protecting neurons from Abeta neurotoxicity and apoptosis, thereby preventing ischemia- or reperfusion-related neuronal death and improving learning and memory retention.

J Nutr. 2006 Mar;136(3 Suppl):810S-812S

Aged garlic extract is a potential therapy for sickle-cell anemia

Sickle-cell anemia is one of the most prevalent hereditary disorders with prominent morbidity and mortality. Oxidative phenomena play a significant role in the disorders pathophysiology. A formulation of garlic (Allium sativum), AGE, has been reported to exert an antioxidant effect in vitro. Researchers evaluated the antioxidant effect of AGE on sickle red blood cells (RBCs).

Five patients (two men and three women, mean age 40+/-15 years, range 24-58 years) with sickle-cell anemia participated in the study. AGE was administered at a dose of 5 mL daily. Whole blood samples were obtained at baseline and at 4 wk, primarily for Heinz body analysis. In all patients, the number of Heinz bodies decreased over the 4-wk period. These data suggest that AGE has a significant antioxidant activity on sickle RBCs. AGE may be further evaluated as a potential therapeutic agent to ameliorate complications of sickle-cell anemia.

J Nutr. 2006 Mar;136(3 Suppl):810S-812S.


1. Steiner M & Lin RI Cardiovascular and Lipid Changes in Response to Aged Garlic Extract Ingestion. J Am Coll Nutr, 13;5:524, 1994.
2. Legnani C, Frascaro M, et al. Effects of a dried garlic preparation on fibrinolysis and platelet aggregation in healthy subjects. Arzneim-Forsch Drug Res 1993;43:119-22.
3. Silagy C, Neil A. A meta-analysis of the effect of garlic on blood pressure. J Hyperten 1994;12(4):463-68.
4. Imai J, et al. Antioxidant and Radical Scavenging Effects of Aged Garlic Extract and Its Constituents. Planta Medica, 60:417-420, 1994,
5. Dorant E, van der Brandt PA, et al. Garlic and its significance for the prevention of cancer in humans: A critical review. Br J Cancer 1993;67:424-29.
6. Kandil OM, Abdullah TH, & Elkadi A. Garlic and the Immune System in humans: its effects on Natural Killer cells. Fed Proc, 46;3:441, 1987.
7. Tadi PP et al. Anticandidal and Anticarcinogenic Potentials of Garlic. Int Clinical Nutr Rev, ,10:423-429, 1990.
8. Growth Stimulatory Effect of Aged Garlic Extract Protein Fraction on Friendly Bacteria. Kokai Tokkyo Koho, Japanese Patent H1-252276.
9. Lau BHS. Detoxifying, Radio-protective and Phagocyte-Enhancing Effects of Garlic. Int Clinical Nutr Rev ,9:27-31, 1989.
10. 2003. Neurosci 122:885-895.
11. 2002. Piante Medicinali. 1(3): 114-128.
12. J. Nutr. 2006;136 Suppl 3:S810-2.
13. Fillion, G. Designer Foods III (Transcript). May 23, 24 and 25, 1994.
14. Fillion, G., Fillion, M., et al. 1997. Ch. 19. In: Nutraceuticals: pp. 189-192.
15. Rozenfeld, V. et al. 1999. April 21-24.
16. ICNPR. July 31-August 4, 2004.
17. FASEB. J. April 2004, 18(6): 600:5.
18. J. Nutr. 2006;136 Suppl 3:S793-5.
19. 1994. Cancer Epidemiol. Biomarkers Prev. 3:155-160.

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