Herbs in History: Garlic
Allium sativum L.
To Know or Not to Know?
In the comedy The Bourgeois Gentleman (Le Bourgeois Gentilhomme in the French original title), the classical French playwright Jean-Baptiste Poquelin (1622-1673), best known as Molière, stages a wealthy tradesman, Monsieur Jourdain, aiming to climb in society and to delete the traces of his earlier lower economic and, hence, social origins. He hires tutors in music, dancing, fencing and philosophy believing that he will acquire the manners of a polished gentleman. In a remarkable scene, the philosophy master, all too aware of the absurd situation and not knowing where to start with, begins with the basics, that is, the difference between poetry and prose. After having invited him to compose verses—resulting in non-sensical verses by Mr Jourdain—the master shifts to prose. Mr Jourdain then marvels at his discovery that he had been living an entire life speaking in prose, without knowing, however, that he was doing so.
Illustration 1: Garlic (Allium sativum L.) in nature (Getty Images
This amusing satire of the pretensions of a naïve Prodigious Snob (as the title piece is sometimes translated) translates in figurative terms a question to be asked in the research on the therapeutic uses of materia medica of the past, which, put in more technical terms, consists in investigating whether ancient therapists were aware of the action, let alone of the physiological mechanisms, of the natural substances they were using to treat patients. The question is more than theoretical speculation. It is about the very possibility understanding therapeutic uses of plants and natural substances attested in ancient treatises that might be key for present-day medical research. Garlic is a case in point (Illustration 1).
Problem with the Traditional Historical Narrative
Garlic (Allium sativum L.) is currently credited with a cardiovascular action, being hypotensive and effective against high cholesterol levels. According to current literature, research establishing this action did not start before the 1950s and the publication of the following two articles:
H. H. Wittig, “The systematic therapy of hypertension with a combination of garlic, mistletoe and chlorophyll” (original title: Die symptomatische Therapie der Hochdruckkrankheit mit einer Knoblauch-Mistel-Chlorophyll-Kombination) in the journal Hippokrates: Informationen aus der medizinischen Wissenschaft und Praxis (Hippokrates. Information from Medical Science and Practice), 16 (1955): 688-690;
V. A. Svechnikov, “Mechanism of action of garlic on the heart and on the blood vessels” (original title: O mekhanizme deistviia chesnoka na serdtse i krovenosnye sosudy) published in the Proceedings of the Leningrad Sanitary and Hygienic Medical Institute (Trudy Leningradskogo Sanitarno-Gigienicheskogo Meditsinskogo Instituta) 34 (1957): 189–192.
Illustration 2: The Madaus brothers, Gerhard, Friedemund, and Hans.
Illustration 3: Madaus G., Lehrbuch der biologischen Heilmittel. Leipzig: Georg Thieme, 1938.
A proof to the contrary of this starting point of the garlic carrier as a hypotensive comes from the all-embracing inventory of natural substances used for therapeutic purposes published by the German physician Gerhard Madaus (1890-1942): Textbook of the Biological Healing Methods (Lehrbuch der biologischen Heilmittel). The history of this work is significant for our purpose here.
Gerhard’s mother, Magdalene Madaus (1857-1925), was a traditional healer who produced the components of a system of ‘complex homoeopathy’ she developed. With his two brothers—Friedemund (1864-1969), a bank clerk, and Hans (1896-1959), a pharmacist—, Gerhard created in 1919 the company Dr Madaus & Co, which was selling herbal medicines and homoeopathic remedies, in addition to related literature, with books and journals (Illustration 2). In 1927, the company sat up a laboratory, followed, in 1932, by a ‘biological research station’ for research on medicinal plants. Four years later, it opened a ‘biological institute’ to pursue research to generate a systematic corpus of data on plants and their applications in medicine. Interestingly—and contrary to what had been mainstream in pharmaceutical research for over a century at that time—Gerhard Madaus was claiming that the several therapeutic effects of plants in traditional knowledge would be lost if research were focusing only on the active principles as extractive chemistry was doing then. For him, instead, an herbal medicine should closely reproduce the complex mixture of elements in whole living plants.
With this in mind, he compiled an encyclopedia of the traditional uses of medicinal plants from the Father of Medicine Hippocrates (5th–4th cent. BCE) to the Father of Homoeopathy, Samuel Hahnemann (1755-1843). This encyclopedia is the Textbook of the Biological Healing Methods (Lehrbuch der biologischen Heilmittel) above (Illustration 3). A part of a great ‘Neo-Hippocratic’ program aimed to reconcile traditional practice and contemporary scientific medicine, the encyclopedia was a monumental work in three volumes totaling over 2,000 pages. It opens with a broad, yet precise and exhaustive survey of the historical and contemporary literature on the therapeutic uses of plants and comprise monographs on each of the plants used in traditional medicine in that time. Each such monography concludes with practical information on the parts of the plants to be used, together with proper dosages, allopathic and homoeopathic, for the different indications.
In the monograph on garlic, Madaus listed a great many historical and traditional uses, covering the period from Pharaonic Egypt to the 1930s. While he did not report any use for the treatment of hypertension in his survey of historical sources, he did mention such indication, though briefly, in his review of modern and contemporary literature. According to him the French physician Henri Leclerc (1870-1955), known as the founder of phytotherapy and author of a Handbook of Phytotherapy. Essays on Therapy with French Plants (Précis de phytothérapie. Essais de thérapeutique par les plantes françaises) first published in Paris in 1927 and several times reedited since (Illustration 4a and 4b), recommended the use of a tincture of garlic “to obtain a hypotensive action”, with 20-30 drops before two meals for two days, with an interruption of two days.
Illustration 4a: Henri Leclerc
Illustration 4b: Henri Leclerc, Précis de phytothérapie. Essais de thérapeutique par les plantes françaises. Paris: Masson, 1927.
Similarly, the German physician Ernst Meyer in Therapie through Plants. An Introduction to Formulae for Plant Therapy with Examples (Pflanzliche Therapie Eine Anleitung mit Beispielen zur RezepturPflanzliche Therapie) first published in Leipzig in 1935, recommended garlic to regulate blood pressure as it reduces pressure and increases, instead, the amplitude of the pulse.
The fact is not so much that the publications referred to by Madaus preceded the articles published in the 1950s that are supposed to have opened the study of the hypotensive effect of garlic, but rather that, in these publications and in Madau’s own encyclopedia, reference is made to traditions for which there are no written traces.
A similar paradox can be found in modern ethnobotanical/ethnopharmacological literature as in an article published in 2008 about traditional uses of plants in the Sannio region in Italy, for example:
The hypotensive effect of garlic is exploited by swallowing crushed cloves wrapped in bread crumbs or in water, or by introducing large quantities of this plant product into the diet. The essence contained in the bulb strengthens the cardiac rhythm, causes vasodilation of the arteries and regulates the pulse; it is, therefore, a precious remedy for the treatment of hyper-tension and arteriosclerosis.
Carmine et al., 2008. Ethnobotanical study of the Sannio area, Campania Southern Italy. Ethnobotany Research and Applications 6 (2008): 255–317. See p. 281.
Returning to the Written Tradition
It might be argued that the absence of written trace on the traditional uses of garlic as a hypotensive agent referred to from Madaus to the article above results from an oral transmission that was not written down or has been lost at some point in time. Nevertheless, it is striking that many of the other uses of garlic found in the literature do appear in the ancient written documentation going as far back as Hippocrates (5th-4th cent. BCE) and the Hippocratics.
In the series of treatises by the Hippocratic physicians dating as far back as the late 5th century BCE, garlic is mostly prescribed in the treatment of a great many gynecological conditions and in some others as ascarids, skin spots, weight excess and related dyscrasia, pain and intestinal inflammation, in addition to a use in ophthalmology not agreed upon by all Hippocratic physicians with some claiming that it made vision dull and others using it to sharpen vision, instead.
Later, in the 1st century CE, Dioscorides in De materia medica does not develop that much the gynecological uses (except an indication as emmenagogue and pain in the womb) but focuses on dermatological uses (superficial wounds, skin spots [dark and white], lichen) and applications in cases of toothache, worms (under the skin and in the intestinal system), chronic cough, and alopecia (Illustration 5).
Illustration 5: Garlic in manuscript New York, Pierpont Morgan Library, M652, 10th cent. Constantinople, f. 16 verso.
Illustration 6: Garlic in manuscript London, British Library, Sloane 4016, ca. 1440, Northern Italy, f. 15 verso.
Since these uses were preserved through the centuries reaching the 20th century as Madaus indicates and since, conversely, tradition as recorded in the 20th century includes hypotensive action, we may hypothesize that the hypotensive action of garlic was already present in ancient medicine. The problem is to properly trace it, as either hyper- or hypotension were not medical concepts of that time even though an abundant corpus of sphygmological knowledge and literature developed in antiquity, particularly with Galen (129-after [?] 216 CE), author of several treatises on the topic: On the causes of pulse, On the differences in the pulse, On the use of pulse in medicine, On the diagnosis through the pulse, and On prognosis through the pulse, in addition to more synthetic treatises as On pulse for beginners and Synopsis on pulse. We thus might suspect that ancient healers used garlic as a hypotensive agent without being aware of this action.
The question might be more complex as the ancient medical literature contains a certain number of bitter substances the relaxing action of which on the wall of the arteries and veins is now well known. Without further considering the bitter and returning to Molière, knowledge of the hypotensive action of garlic in history is in effect the paradoxical situation of Mr Jourdain speaking in prose without having ever known that he was doing so. In this view, the problem we are facing changes and consists in tracing the hypotensive activity of garlic through its applications as described in ancient texts. This would allow us to assume that garlic effects were known.
The main property of garlic according to the Hippocratics leads us in that direction. For them, indeed, garlic was “warm, excretive, and diuretic. It is excretive and diuretic because of its purgative quality”. This action appears in Dioscorides, too, where we read that garlic provokes urination, eliminates water out of the body (an action that is even repeated in the text) and is good for the treatment of dropsy. A similar action can be found in the Qanun by ibn Sina (890-1037), best known in the Middle Ages as Avicenna, where, however, it was expanded to become a general property, acting on “urination and menstruation; [it] expels the placenta ...phlegm, and worms as a laxative ...”. Later, in the Western Middle Ages, the 14th -century Treatise on Herbs (Tractatus de herbis) is more restrictive, instead, and recommends use of garlic to eliminate worms, open the urinary tract (and thus counteracting dysuria and stranguria), and to provoke menstruation, in addition to returning to the Hippocratic negative effect on vision (Illustration 6).
This clearly stated excretive action, specifically the diuretic action, hints at an awareness of the effect of garlic on the circulatory system. This is particularly the case of the application in the treatment of dropsy and the drainage of excessive liquid through accrued cardiovascular activity.
This conclusion is of paramount importance as it suggests that, even though the ancient nosological system does not correspond to the present one and apparently makes it impossible to trace medical conditions whose ancient treatments might be of interest nowadays, another approach, consisting in tracing the actions of the plants and not the pathological processes for which they were prescribed, leads to identify therapeutic uses that are not identified as such in the ancient literature. In other words, it might be that ancient physicians were aptly using therapeutic methods of which they did not know and understand why and how they worked but knew that they worked.
Assuming that this is correct, the traditional abundant use of garlic in Mediterranean cuisine takes a new dimension that goes way beyond the culinary art: it is a preventive medicine administered on a daily basis. This, the ancient did know it.
European Union Committee on Herbal Medicinal Products (HMPC)
Herbal Medicine: Expanded Commission E: Garlic
Articles (selection, chronological order)
Li M. et al. 2022. Roles and mechanisms of garlic and its extracts in atheroscleorisi: A review. Frontiers in Pharmacology 13:954938 (03 October 2022).
De Greef D. et al. 2021. Anticancer potential of garlic and its bioactive constituents: A systematic and comprehensive review. Seminars in Cancer Biology 73 (Aug. 2021): 219-264.
Mondal A. et al. 2021. Garlic constituents for cancer prevention and therapy: From phytochemistry to novel formulations. Pharmacological Research Aug. 24, 2021: 105837.
Batiha G.E. et al. 2020. Chemical Constituents and Pharmacological Activities of Garlic (Allium sativum L.): A Review. Nutrients 12(3) (Mar. 2020): 872.
Ansary J. 2020. Potential Health Benefit of Garlic Based on Human Intervention Studies: A Brief Overview. Antioxidants (Basel) 9(7) (Jul. 2020): 619.
Martins N., Petropoulos S., Ferreira I.C. 2016Chemical composition and bioactive compounds of garlic (Allium sativum L.) as affected by pre- and post-harvest conditions: A review. Food Chemistry 211 (Nov 15 2016): 41-50.
Hosseini A., Hosseinzadeh H. 2015. A review on the effects of Allium sativum (Garlic) in metabolic syndrome. Journal of Endocrinological Investigation 38(11) (Nov. 2015): 1147-1157.
Majewski M et al. 2014 Allium sativum: facts and myths regarding human health. Rocz Panstw Zakl Hig 65(10 (2014): 1-8.
Shouk R. et al. 2014. Mechanisms underlying the antihypertensive effects of garlic bioactives. Nutrition Research 34(2) (Feb. 2014): 106-115.
Bayan L. et al. 2014. Garlic : a review of potential therapeutic effects. Avicenna Journal of Phytomedicine 4(1) (2014): 1-14.
Varshney R., and Budoff M.J. 2016. Garlic and Heart Disease. The Journal of Nutrition 146(2) (Feb. 2016). Supplement—2014. International Garlic Symposium: Role of Garlic in Cardiovascular
Disease Prevention, Metabolic Syndrome, and Immunology 2014: 416S-421S.
Mikaili P. et al. 2013. Therapeutic uses and pharmacological properties of garlic, shallot, and their biologically active compounds. Iranian Journal of Basic Medical Science 16(10) (Oct. 2013): 1031-1048.
Bauer Petrovska B. and Cekovska S. 2010. Extracts from the history and medical properties of garlic. Pharmacognosy Review 4(7) (Jan.-Jun. 2010): 106–110.
Winnerling T. 2010. Der Fürsten-Theriak. Die wundersamen Knoblauchkräfte der Frühen Neuzeit [The Prince's theriac. The marvellous early modern powers of garlic]. Würzburger medizinhistorische Mitteilungen 29 (2010): 325-362.
Ried K. et al. 2008. Effect of garlic on blood pressure: A systematic review and meta-analysis. BMC Cardiovascular Disorders 8(13) (2008).