Herb Profile

Hops

Humulus lupulus L.

Family: Cannabaceae

Introduction

Hops is a perennial vine growing vertically to 33 feet with dark green, heart-shaped leaves.^1,2,3 The male and female flowers grow on separate vines.^1,3 Hops are the dried yellowish-green, cone-like female flowers or fruits (technically referred to as strobiles).^1,4 Originally native to Europe, Asia, and North America,⁵ several varieties of hops are now cultivated in Germany, the United States, the British Isles, the Czech Republic, South America, and Australia.^4,6 Although still wild in Europe and North America, commercial hops come exclusively from cultivated plants.^1,7 The leaves, shoots, female flowers (hops), and oil are the parts of the plant used commercially.⁸

History and Cultural Significance

The name hops is derived from the Anglo-Saxon word hoppan meaning to climb.^5,9 The species name lupulus is Latin for small wolf, referring to the plant's habit of "wolfing" or climbing on other plants, as a wolf would climb on a sheep.^2,9 The beer brewing industry accounts for 98% of the world use of hops.^1,3 Originally used as a preservative, hops were later additionally used to add a bitter flavor to beer.¹⁰ The earliest record of hopped beer is in 822 CE.³ The cultivation of hops spread in Europe during the Middle Ages because beer was served with every meal.³

Hops have been used as a food and for flavoring food and as a perfume scent for over 2500 years.¹¹ Pliny the Elder (circa 23-79 CE) mentions Romans eating young hop shoots.⁹ The young spring shoots are still eaten in Belgium, France, and England in the same ways that asparagus is eaten.^2,12 The flowers are a natural source of food flavoring.^2,13 They have flavored cereal, beverages, mineral waters, spices, sauces, tobacco, and alcoholic beverages other than beer.^10,11,14 Hops have been used in perfume, especially the spicy or oriental types,^10,14 to give body to dry hair, and in skin creams and lotions.^10,15

Medicinally, hops are mainly used as a sedative.¹ With other herbal sedatives, hops can be beneficial for sleeplessness and nervousness.^6,16 Efficacy has long been established, but the exact mechanism for sedation is still unknown.⁷ Hops also contain antispasmodic, diuretic, calming, sleep promoting, hypnotic, and antimicrobial properties.^4,8,10,16,17

The sedative constituents are believed to be in the aromatic oils, hence the rationale behind the traditional use of ÒsleepÓ pillows made of hops.¹⁴ The aromatic oils may also have estrogenic effects as noted from observations of young women who reportedly often experienced early menstrual periods after harvesting the strobiles in hops fields.¹⁸

Traditionally hops were used for nervousness, insomnia, excitability, ulcers, indigestion, and restlessness associated with tension headache.¹³ Additional folk medicine uses include pain relief, improved appetite, and as a tonic.⁹ A tea made of hops was ingested for inflammation of the bladder.⁷ Native American tribes used hops for insomnia and pain.^5,8 Hops are employed in Ayurvedic (Indian) medicine for restlessness and in traditional Chinese medicine for insomnia, stomach upset and cramping, and lack of appetite.⁵ Clinical studies in China report promise for the treatment of tuberculosis, leprosy, acute bacterial dysentery, silicosis (respiratory condition caused by the inhalation of silica dust), and asbestosis (respiratory condition caused by the prolonged inhalation of asbestos particles).^5,10 Externally, it has been applied to treat dandruff, ringworm, sores, ulcers, skin injuries, acne, and to alleviate pain and itching.^6,7 In aromatherapy, hops have been used for skin care, breathing conditions, nervousness, nerve pain, and stress-related conditions.¹⁴

Hops are approved in various monographs and pharmacopeias as a treatment for excitability, lack of appetite, mood disturbances (restlessness, anxiety), sleep disturbances, sleeplessness, and tenseness.^2,16,17,19

Modern Research

One laboratory study has demonstrated antimicrobial activity in hops and has suggested that hops constituents may be useful in mouthwash.²⁰ Several clinical trials have supported the efficacy of a combination of hops with valerian root (Valeriana officinalis L., Valerianaceae) for improving sleep.^{21,22,23,24,25} No published clinical studies to date have examined the effectiveness of hops alone for any traditional use.

Future Outlook

There is a fixed worldwide demand for hops, dependent on beer consumption, with variable supply, which results in shortages and surpluses in any given year.²⁶ World production of hops is cyclical and typically peaks every 7-10 years followed by several years of surpluses and depressed market prices. A relatively consistent supply of hops is assured by the fact that they are grown in numerous places for specific markets.²⁶

—Gayle Engels and Joyce Juan

References

1. Bruneton J, ed. Pharmacognosy, Phytochemistry, Medicinal Plants. 2nd ed. Paris: Lavoisier; 1999.

2. Onstad D. Whole Foods Companion: A Guide for Adventurous Cooks, Curious Shoppers & Lovers of Natural Foods. White River Junction, VT: Chelsea Green Publishing Company; 1996.

3. Tucker AO, Debaggio T. The Big Book of Herbs. Loveland, CO: Interweave Press; 2000.

4. British Herbal Pharmacopoeia. Dorset, UK: British Herbal Medicine Association; 1996.

5. Blumenthal M, Goldberg A, Brinckmann J, eds. Herbal Medicine: Expanded Commission E Monographs. Austin, TX: American Botanical Council; Newton, MA: Integrative Medicine Communications; 2000.

6. Tyler VE, Foster S. Tyler's Honest Herbal. 4th ed. Binghamton, NY: Haworth Herbal Press; 1999.

7. Wichtl M, Brinckmann J. Herbal Drugs and Phytopharmaceuticals. Stuttgart: Medpharm GmbH Scientific Publishers; 2004.

8. Bown D. The Herb Society of America New Encyclopedia of Herbs and Their Uses. London: Dorling Kindersley Ltd.; 2001.

9. Grieve M. A Modern Herbal. Vol. 1. New York: Dover Books; 1971.

10. Duke J, ed. Handbook of Medicinal Herbs. Boca Raton, FL: CRC Press; 1985.

11. Arctander S. Perfume and Flavor Materials of Natural Origin. Carol Stream, IL: Allured Publishing Corporation; 1994.

12. Davidson A. The Oxford Companion to Food. London: Oxford University Press; 1999.

13. Barnes J, Anderson L, Phillipson J, eds. Herbal Medicines: A Guide for Health Care Professionals. London: Pharmaceutical Press; 2002.

14. Lawless J. The Illustrated Encyclopedia of Essential Oils: The Complete Guide to the Use of Oils in Aromatherapy and Herbalism. Dorset, UK: Element Books, Ltd; 1995.

15. D'Amelio FS. Botanicals: A Phytocosmetic Desk Reference. Boca Raton, FL: CRC Press LLC; 1999.

16. Blumenthal M, Busse WR, Goldberg A, Gruenwald J, Hall T, Riggins CW, Rister RS, eds. Klein S, Rister RS, trans. The Complete German Commission E MonographsÑTherapeutic Guide to Herbal Medicines. Austin, TX: American Botanical Council; Boston: Integrative Medicine Communication; 1998.

17. Bradley P. British Herbal Compendium. Vol. 1. Dorset, UK: British Herbal Medicine Association; 1992.

18. Milligan SR, Kalita JC, Heyerick A, et al. Identification of a potent phytoestrogen in hops (Humulus lupulus L.) and beer. J Clin Endocrin Metab. 1999;83(6):2249-2252.

19. European Scientific Cooperative on Phytotherapy. ESCOP Monographs. 2nd ed. New York: Thieme; 2003.

20. Bhattacharya S, Virani S, Zavro M, Haas GJ. Inhibition of Streptococcus mutans and other oral Streptococci by hop (Humulus lupulus L.) constituents. Economic Botany 2003;57(1):118-125.

21. Schellenberg R, Sauer S, Abourashed EA, Koetter U, Brattstrom A. The fixed combination of valerian and hops (Ze91019) acts via a central adenosine mechanism. Planta Med. July 2004;70(7):594-597.

22. Fussel A, Wolf A, Brattstr?m. Effect of a fixed valerian-hop extract combination (Ze 91019) on sleep polygraphy in patients with non-organic insomnia: a pilot study. Eur J Med Res. 2000;5:385-390.

23. Vonderheid-Guth B, Todorova A, Brattstrom A, Dimpfel W. Pharmacodynamic effects of valerian and hops extract combination (Ze 91019) on the quantitative-topographical EEG in healthy volunteers. Eur J Med Res. 2000;5:139-144.

24. Rodenbeck A, Simen S, Cohrs S, et al. Alterations of the sleep stage structure as a feature of GABAergic effects of a valerian-hop preparation in patients with psychophysiological insomnia. Somnologie. 1998;2:26-31.

25. Schmitz M. Jackel M. Comparative study for assessing quality of life of patients with exogenous sleep disorders (temporary sleep onset and sleep interruption disorders) treated with a hops-valerian preparation and a benzodiazepine drug [in German]. Wien Med Wochenschr. 1998;148:291-298.

26. Ministry of Agriculture and Forestry to Manatu Ahuwhenua, Ngaherehere New Zealand. International Market for Hops. Available at: http://www.maf.govt.nz/mafnet/rural-nz/profitability-and-economics/producer-boards/structure-of-hop-industry/hopmb002.htm. Accessed August 31, 2005.