Garlic as medicine?

Thanks for your patience. I didn’t get to post as often as I would’ve liked. While cooking over the past few weeks and blogging, I couldn’t help , but notice how garlic is essential to cooking. It is found in a variety of cultures, prepared in a multitude of ways. It can be the main flavor or a subtle nuance. It’s culinary crazy glue!. Anything can taste better with a little garlic. My family, on occasion, has been known to consider it the 4th unmentioned member of the Holy Trinity. The Catholic Trinity is The Father, The Son and the Holy Spirit. Add garlic to that and you’ll begin to understand how valued it is in our home. When I was growing up, garlic cured what ailed you. When I got a cold, my Mother inundated me with dishes amassed with hot stock and garlic. NO DAIRY. A lot of cultures give credit to garlic for its healing properties. Just look at good, old-fashioned Matzo Ball soup. It’s so delicious, I almost considered converting to Judaism just to get the recipe. Turns out I didn’t have to go to that extreme. The healing properties afforded garlic got me curious as to how much research out there actually supported the hundreds of years use of garlic medicinally. Although garlic has been used for its medicinal properties for thousands of years, research into what causes its antimicrobial properties is limited and not as recent as I expected. A reappearance in the use of natural herbal alternatives and complementary medicine has brought the use of medicinal plants to the forefront of pharmacological investigations, and many new drugs could possibly be discovered. (www.botanicalmedicine.org/References/09swrefs/WinstonMDRRefs.pdf)

Garlic has a complex protection structure as complicated as the human immune system. Garlic can defend itself from insects and fungi by producing allicin through an enzymatic process when cellular damage occurs. Suffice it to say, allicin is nature's original insecticide. Allicin was discovered in 1944 by C. J. Cavallito in the Journal of the American Chemistry Society, who documented its powerful antimicrobial activity.(5) Allicin has been patented for its antifungal activity in test tubes, but no clinical trials have been conducted as of late with allicin. It could not be packaged into a drug or commercial product because it is unstable, it is not bioavailable to the body, and it contains a strong, often offensive odor. Unfortunately, Allicin is thought to be scientifically worthless inside the body. It is currently considered by the scientific community as just a transitory compound which quickly breaks down into other compounds.(2)

Chemically, allicin is known as 2-propene-1-sulfinothioc acid S-2-propenyl ester; thio-2-propene-1-sulfinic acid S-allyl ester, for those who care.(2) Allicin is produced by an enzymatic reaction when raw garlic is either crushed, pressed, minced or some other cellular damage occurs. The enzyme, alliinase, stored in a separate compartment in garlic, combines with a compound called allicin in raw garlic and produces allicin.(1)

Cooking, aging, crushing and otherwise processing garlic causes allicin to be decomposed into other compounds. According to two studies of garlic preparations, allicin decreased to non-detectable amounts within one(4) to six(10) days. To stop the decomposition caused by the cellular damage of allicin, some tried to make allicin and alliinase more stable so that these compounds would not come together until after they are ingested with the hopes of producing allicin inside of the body. Once again attempt are thwarted because the production of allicin within the body is different from that created in a test tube because stomach acid destroys alliinase and other intestinal fluids significantly reduce the quantity of allicin that can be made. Simulated stomach fluids and simulated intestinal fluids have often been used to recreate the environment of typical digestion. Much to my disappointment, alliinase, the catalyst for converting allicin to allicin, has been shown to have virtually no bioavailability at pH 3 or below, an acidic environment commonly found in the stomach.7 In addition , there was a 99% loss in allicin creation observed immediately after contact with simulated stomach fluids and simulated intestinal fluids. This process would happen if garlic powder was ingested orally.(10) So while this study shows that unless a garlic powder bypasses the stomach, the amount of allicin still created is insignificant.

So based on this science or the lack of it, could garlic still be considered a functional food? Forms of garlic, which contain no allicin (e.g., cooked, steamed, microwaved and aged garlic extract), have shown a range of benefits in studies. So one would think it is logical that compounds other than allicin might be responsible for such benefits. Currently, over 100 compounds have been identified in garlic preparations.(4) Right now, S-allyl cysteine appears to be a very promising compound with good absorption.(8) The pharmacokinetic studies of S-allyl cysteine show quick absorption and almost 100% bioavailability after administering orally. Concurrently, since both the safety and effectiveness of S-allyl cysteine have been reported, this compound may play an important role in garlic's medicinal effects.(6,9)

Though individual compounds, such as S-allyl cysteine, have demonstrated action in studies and present 100% bioavailability by the body, it is likely that a “working together” of many compounds could provide the benefits of garlic. It would stand to reason that much more research needs to be conducted. So continue to enjoy your garlic for its taste alone. Any other benefits are icing on the cake. Mangia!

Sopa De Ajo Mexicano (Mexican Garlic Soup)
2 Tablspoons Flour
2 Tblspn Butter
2 heads of garlic (yes, you read that correctly. 2 whole heads, cloves separated and peeled
2 tomatoes, seeded and finely chopped
1 fresh poblano chile pepper, seeded and minced
1 qt of chicken stock
Salt & pepper to taste
4 whole eggs

In a food processor, puree garlic as fine as possible. In a medium saucepan over medium high heat, melt butter. Add flour, making a roux. Cook for about 1 minute. Add garlic to roux and sauté for 2 minutes. Then add the poblano pepper. Saute for additional 4-5 minutes. Then add the tomatoes, cooking to bring out the sweetness of the tomato (about 3-4 minutes). Season with salt and pepper. Add chicken stock and bring to a boil. Simmer for 15 minutes. Bring back to a boil. With soup at boil, slip eggs in gently so the yolk doesn't break. When eggs are poached, serve in bowls with one egg per bowl. You can top with fresh, chopped parsley and grated parmesan cheese. Serve with crusty bread for dipping. Makes 4 servings.

References:
1. Allicin. The Merck Index. 1989. (Budavari, S. ed.), 11th ed. p. 244. Merck and Co. Rahway, New Jersey.
2. Amagase, H., Petesch, B., Matsuura, H., Kasuga, S. and Itakura, Y. Intake of garlic and its bioactive components. J. Nutr. 131(3S): 955S-962S, 2001.
3. Block, E. The organosulfur chemistry of the genus Allium – implications for the organic chemistry of sulfur. Angew. Chem. Int. Ed. Engl. 31: 1135-1178, 1992.
4. Brodnitz, M.H. Pascale, J.V., and Derslice, L.V. Flavor components of garlic extract. J. Agr. Food. Chem. 19(2):273-275, 1971
5. Cavalitto, C.J. et al. 1944. J. Am. Chem. Soc. 66: 1950.
6. Kodera, Y. 1997. Dietary Tolerance/Absorption/Metabolism of Garlic. Ch. 11. In: Nutraceuticals: Designer Foods III Garlic, Soy and Licorice (Trumbell, Ct: Food & Nutrition Press), Paul Lanchance, ed., pp. 95-105.
7. Lawson, L. D., Ransom, D. K. and Hughes, B. G. Inhibition of whole blood platelet-aggregation by compounds in garlic clove extracts and commercial garlic products. Throm. Res. 65: 141-156, 1992.
8. Nagae, S., Ushijima, M., Hatono, S., Imai, J., Kasuga, S., Matsuura, H., Itakura, Y. and Higashi, Y. 1994. Pharmacokinetics of the garlic compound S-allyl cysteine. Planta Med. 60: 214-217.
9. Rosen, R. Determination of allicin and S-allyl cysteine in human plasma and urine after consumption of garlic and garlic products. Phytomed. 7(2): 51, 2000.
10. Yu. T-H, and Wu, C-M. Stability of allicin in garlic juice. J. Food Sci. 54(4): 977-981, 1989.