Garlic and Digestive Health
Sue McGarrigle ND DipION
What is tucked away in the seeds, rinds, leaves, oils and roots of plants is awesome and I never underestimate the power or synergy our food has to not only alleviate symptoms but keep us free from disease. Isn’t that obvious? It is the core of nutrition. Antibiotic resistance and the mutation of microbes is just one element where certain foods may be needed to come back ‘into their own’ and medical science is constantly reviewing plant compounds in an effort to find solutions. At the time when antibiotics and other pharmacy products did not exist, a bulb of garlic itself represented a whole pharmacy industry due to the broad spectrum of effects.
From 5000 years ago it has been a staple used by the Chinese, the Egyptians, the Romans, the Greeks right through to the Second World War. Louis Pasteur demonstrated, in 1858, that garlic could kill infectious germs. Albert Schweizer, in the early and mid-20th century, used garlic in Africa to cure typhoid fever and cholera. Garlic was used throughout World War I to treat battle wounds and to cure dysentery. During World War II, garlic was known as "Russian penicillin" because it was so effective in treating wound infections when adequate antibiotics were not available. This is due to its own smelly weapons which are activated as a result of insects invading its outer coat or when cloves are crushed, its volatile oil with its organosulfur components (OSCs) the active principles responsible for its biological activity having been part of our own arsenal to maintain microbial balance in the gastro-intestinal tract for thousands of years. Garlic can effectively kill or inhibit bacteria, viruses, parasites, fungi, yeasts, and moulds.
There are other natural antimicrobial agents which may be used and are recommended but for me they fall short due to their more aggressive action, I think it is important that we use foods which contribute to the correction of dysbiosis without affecting our beneficial microflora. Garlic can help to achieve this. In this day and age it is vital to maintain gut homeostasis and good immunity which are pretty much at the base of most diseases and inflammation. Our complicated microbial world (of which we know little) has yielded recent evidence of the far reaching effects our microflora have in distal organs and certain diseases. Protection of the commensal population against opportunistic pathogens including antibiotic resistant strains that are confirmed to have a susceptibility to Garlic’s raw compounds is pretty extensive, and to my mind extremely protective and therapeutic where needed. Numerous diseases may be triggered by infectious processes caused by opportunistic pathogens which garlic may help or prevent.
Garlic is bacteriostatic and bactericidal; its antibacterial activity widely attributed to allicin and has been proven to be effective against gram-positive, gram-negative, and acid-fast bacteria. These include but not all are listed here- species of Salmonella, Escherichia coli, Pseudomonas, Proteus, Staphylococcus aureus, Klebsiella (which is linked to Ankylosing Spondylitis), Micrococcus, Bacillus, Clostridium, Mycobacterium, Shigella and Helicobacter. Bacteria such as E.coli contribute to gastrointestinal inflammation and intestinal permeability. It has been documented that garlic exerts a differential inhibition between beneficial intestinal microflora and potentially harmful Enterobacteria that cause primary infections of the human gastrointestinal tract. Even bacteria resistant to antibiotic agents are sensitive to extracts of garlic. Garlic is effective against specific bacteria that are notorious for developing resistant strains, such as Staphylococcus, Mycobacterium, Salmonella, and species of Proteus.
Antifungal activity was first established in 1936. Many fungi are sensitive to garlic, including species of Aspergillus, Candida, Torulopsis, Trichophyton, Cryptococcus, Trichosporon and Rhodotorula. Allicin interferes with RNA production and lipid synthesis. If RNA cannot be produced, or produced in less amount then protein synthesis will be severely affected. If amino acids and proteins cannot be produced then growth and development of the organism will not occur as they are essential for all parts of cell structure. Also, as lipid synthesis is affected, other parts of the cell are interfered with; the main effect being that the phospholipid biolayer of the cell wall cannot form correctly.
Garlic is recommended in SIBO (small intestinal bacterial overgrowth) - the bacteria that are most commonly overgrown are anaerobes such as Bacteroides and Clostridium and aerobes Streptococcus, Escherichia coli, Staphylococcus and Klebsiella in 11%. In one study, the findings showed E coliin 37%, Enterococcus species in 32%, Klebsiella pneumoniae in 24%, and Proteus mirabilis in 6.5%.
Several studies have shown that Garlic is effective as an antiparasitic including protozoa such as Blastocystis hominis and Entamoeba histolytica. There have been several studies examining the use of alternative agents in the treatment of Blastocystis infection which is becoming more prevalent in Europe.
For example, Yakoob et al studied the in vitro efficacy of garlic and other dietary herbs, compared with that of metronidazole, in the treatment of Blastocystis infection in both control subjects and patients with IBS. The authors evaluated the efficacy of garlic and metronidazole at concentrations of 0.01 and 0.1 mg/ml in suppressing the growth of Blastocystis. They found that garlic and metronidazole were equally effective at both concentrations. The isolates of Blastocystis were not as sensitive to the other herbs tested, which included ginger, black pepper and white cumin. Garlic is also established as a well known antigiardial.A weakness of conventional antibiotics apart from side effects is that they are not effective against viral infections. Garlic has shown activity against influenza A and B, cytomegalovirus, rhinovirus, human immunodeficiency virus, herpes simplex virus 1, herpes simplex virus 2, viral pneumonia, and rotavirus. Garlic’s components allicin, diallyl trisulfide and ajoene have all been shown to be active.
Garlic’s antimicrobial benefits are enhanced as it also stimulates the body’s natural defences against pathogens thereby combining its effects against infectious disease. Garlic can also be considered an excellent preventive and protective agent to reduce gastric pathologies. Garlic has radical scavenging and anti-oxidant activity as well as anti-inflammatory activity. Garlic appears to enhance the functioning of the immune system by stimulating certain cell types, such as macrophages, lymphocytes, natural killer (NK) cells, dendritic cells, and eosinophils, by mechanisms including modulation of cytokine secretion, immunoglobulin production, phagocytosis, and macrophage activation.
Apart from which let’s not forget Garlic’s other multiple benefits in Cardiovascular disease, blood sugar balance, insulin resistance, chemically induced hepatotoxicity, in maintaining urinary and prostate health, respiratory health (allicin is excreted partly by the respiratory organs), liver and kidney health, aiding against the common cold, flu, fatigue and in certain cancers.
Some people are sensitive to garlic and its sulphurous compounds. The use of slow release freeze dried garlic can not only reduce these responses but also the odiferous effects that are normally seen.
