from capillaries. In past times in Europe, the herb was used prior to surgery to lessen bleeding, and even today some European doctors prescribe bil-berry extracts before operations to reduce post-operative bleeding. Claims have been made that bilberry may lower blood pressure.
Vision
Bilberry has been shown to improve vision, es-pecially night vision. During World War II, pilots and navigators of the English Royal Air Force consumed large quantities of bilberry preserves, particularly before night missions, in the belief that this improved vision. The proposed explana-tion is improved blood flow to the capillary-rich retina of the eye. The resulting improved eye func-tion has been said to reduce eye fatigue and lessen the incidence of cataracts and common myopia (near-sightedness).
Diabetes
The berries and especially the leaves of bilberry have been used in folk-medicine treatment of diabe-tes. Bilberry leaf has a reputation as a “blood sugar-reducing” drug, useful in “antidiabetic” (against dia-betes) teas. Although it is not widely used to treat diabetes today (insulin therapy has become stan-dard treatment), it is interesting that very high lev-els of chromium are found in bilberry leaves, and that there has been suspicion that chromium may have a role to play in the treatment of diabetes.
Also, myrtillin (methoxylated glucoside of gallic acid) in bilberry leaf has been shown to reduce hyperglycemia and normalize blood sugar level.
An allied question that has not yet been suffi-ciently clarified is whether or not the improve-ments in blood circulation associated with the use of bilberry (discussed above) are useful for the treatment of circulatory disorders associated with diabetes. As noted below, because of toxicity the consumption of bilberry leaf is generally discour-aged today. Insulin therapy can debilitate some peo-ple, and herbal treatments capable of safely reducing the need for insulin could be advantageous.
Digestive disorders and mucous membrane inflammation
Bilberry (both leaf and berry) tea has been used as a treatment for diarrhea and as a relief for nau-sea and indigestion. Bilberry has considerable tan-nin content, and the astringent action of the tantan-nins is believed to be responsible for its effectiveness in treating digestive disorders, as well as for topical
(surface) treatment of mild inflammation of the mu-cous membranes of the mouth and throat. Numerous herbs with tannins are also known to have the same useful properties, and bilberry is not especially use-ful for these purposes, although some over-the-counter herbal preparations with bilberry are avail-able in Europe specifically for digestive disorders.
As noted below, the leaf is toxic and prolonged consumption is hazardous. Fresh berries seem less effective than dried, older berries for treating di-gestive disorders, perhaps because the tannins are not in a suitable chemical form until after drying has taken place.
Urinary tract health
Bilberry has at least some of the beneficial prop-erties of cranberry for maintaining urinary tract
Vaccinium myrtillus 173
Vaccinium myrtillus (bilberry)
function and curing infections (see chapter on cran-berry for details).
Antioxidant
Flavonoids such as found in bilberry fruits are natural antioxidants, which are medicinally effec-tive because they disarm damaging free radicals.
Free radicals are highly reactive chemical fragments produced during metabolism in the body, that can impair cell function.
Toxicity
Fresh berries may cause diarrhea in some indi-viduals, but are not considered toxic. However, the leaves must not be consumed (for example in tea) over a long period of time, because they are poi-sonous. Although bilberry leaf tea is sometimes en-countered in herbal therapy, its use is hazardous and not recommended.
Chemistry
Anthocyanidin flavonoids responsible for the deep bluish color (often in the form of colorless precursors, proanthocyanidins, in the fresh plant) are believed to be the key medicinal compounds of bilberry. The most significant bioflavonoid in berry appears to be myrtocyan. Dried berries of bil-berry contain about 0.7% anthocyanins. The dried berries of several other wild species of Vaccinium have been shown to have much higher content of anthocyanins, so that it is possible that future re-search may show that these other species are even more desirable as medicinal plants than bilberry.
Other medicinally significant constituents (tannins, myrtillin, chromium) are discussed above.
Non-medicinal Uses
The berries were extensively eaten by Native Americans, including the Kootenay, Carrier, and Shuswap tribes. As with other Vaccinium species, bilberry fruit has long been popular in both Europe and North America for jams, jellies, preserves, pie fillings, liqueurs, and wines. Bilberry is of value as a nurse crop for Douglas fir seedlings. This attrac-tive, hardy, shade-tolerant, low-growing shrub makes an interesting edible landscape, which is very orna-mental in the autumn when the leaves turn red. Root cuttings can be transplanted to disturbed sites to re-duce erosion, at the same time providing a natural food and cover for wildlife. In some parts of the Rocky Mountains problems with black and grizzly bears could be reduced through effective manage-ment of natural stands of bilberry. A larger supply
of the berries would reduce bear foraging in popu-lated areas and campsites.
Agricultural and Commercial Aspects Bilberry is harvested mostly from native stands in North America and Europe and has consequently re-ceived much less attention from plant breeders than the cultivated species of Vaccinium, including the cranberries and blueberries. Most cultivated blueber-ries are stimulated to produce many young flowering and fruiting branches by heavy pruning of the shrubs. However, this practice is unsuitable for bil-berry, which produces most of its fruit at the base of older branches.
Bilberry has a well-deserved reputation as a use-ful herbal medicine and therefore promises a grow-ing market. North American wild bilberry is not readily accessible (the plant grows in mountainous areas) and so cultivation is desirable. Although not extensively cultivated in North America, natural stands are known to produce up to 100 kg (fresh weight) of berries/ha; a much higher production is likely possible under cultivation. There is consider-able information in the European (foreign language) literature on cultivation and management techniques.
While there is a large available supply from Eu-rope, the development of a North American supply is a worthwhile enterprise.
Myths, Legends, Tales, Folklore, and Interesting Facts
•
The name bilberry is derived from the Danish bollebar, meaning dark berry. However, not all berries are dark, and a white-fruited ornamental form is known.•
North American Indians preserved berries of Vac-cinium species in various ways. In the North, ber-ries were placed in seal oil, or stored in leather bags deposited in the permafrost. Indians com-monly dried berries in the sunshine or by a fire.•
During the latter part of the First World War, England experienced a shortage of aniline dye, formerly imported from Germany, and the pig-ments from blue-black berries were substituted.So much of the bilberry crop was purchased by dye manufacturers that there was little available for making jam.
Selected References
Amouretti, M. 1972. Therapeutic value of Vaccinium myrtillus anthocyanosides in an internal medicine de-partment. Therapeutique 48: 579–581. [In French.]
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Azar, M., Verette, E., and Brun, S. 1987. Identification of some phenolic compounds in bilberry (Vaccinium myrtillus) juice. J. Food Sci. 52: 1255–1257.
Badescu, G, and Badescu, L. 1977. Basic elements in the cultivation technology of bilberries (Vaccinium myrtillus). Prod. Veg. Hortic. 26(2): 54–60. [In Ro-manian.]
Bertuglia, S., Malandrino, S., and Colantuoni, A. 1995.
Effect of Vaccinium myrtillus anthocyanosides on ischaemia reperfusion injury in hamster cheek pouch microcirculation. Pharmacol. Res. 31: 183–187.
Bonati, A, and Crippa, F. 1978. Stability of antho-cyanosides from Vaccinium myrtillus L. in pharma-ceutical formulations. Fitoterapia 49: 10–15.
Cignarella, A., Nastasi, M., Cavalli, E., and Puglisi, L.
1996. Novel lipid-lowering properties of Vaccinium myrtillus L. leaves, a traditional antidiabetic treat-ment, in several models of rat dyslipidaemia: a com-parison with ciprofibrate. Thromb. Res. 84: 311–322.
Colatuoni, A., Betuglia, S., Magistretti, M.J., and Don-ato, L. 1991. Effects of Vaccinium myrtillus antho-cyanosides on arterial vasomotion. Arzneimittel-Forschung 41: 905–909.
Contestabile, M.T., Appolloni, R., Suppressa, F., D’alba, E., and Pecorelli, B. 1991. Prolonged treatment with high dosage of Vaccinium myrtillus anthocyanosides:
electrophysiological response in myopic patients.
Boll. Oculist. 70: 1157–1169. [In Italian.]
Cristoni, A., and Magistretti, M.J. 1987. Antiulcer and healing activity of Vaccinium myrtillus anthocyano-sides. Farm. Ed. Pratica 42(2): 29–44.
Colantuoni, A., Bertuglia, S., Magistretti, M.J., and Donato, L. 1991. Effects of Vaccinium myrtillus anthocyanosides on arterial vasomotion. Arzneimittel-forschung 41: 905–909.
Dierking, W., and Dierking, S. 1993. European Vac-cinium species. Acta. Hortic. 346: 299–304.
Dombrowicz, E., Zadernowski, R., and Swiatek, L. 1991.
Phenolic acids in leaves of Arctostaphylos uva-ursi L., Vaccinium vitis-idaea L., and Vaccinium myrtillus L.
Pharmazie 46: 680–68.
Flower-Ellis, J.G.K. 1971. Age structure and dynamics in stands of bilberry (Vaccinium myrtillus L.). Institu-tionen for skogsekologi, Skogshogskolan, Stockholm, Sweden. Rapporter och uppsatser No. 9. 57 pp.
Fraisse, D., Carnat, A., and Lamaison, J.L. 1996. Poly-phenolic composition of the leaf of bilberry. Ann.
Pharm. Fr. 54: 280–283. [In French.]
Friedrich, H., and Schonert, J. 1973. Tannin-producing substances in the leaves and fruits of the bilberry.
Arch. Pharm. (Weinheim) 306: 611–618. [In Ger-man.]
Friedrich, H., and Schonert, J. 1973. Phytochemical in-vestigation of leaves and fruits of Vaccinium myrtillus.
Plant Med. 24(1): 90–110. [In German, English sum-mary.]
Giba, Z., Grubisic, D., and Konjevic, R. 1995. The in-volvement of phytochrome in light-induced germi-nation of blueberry (Vaccinium myrtillus L.) seeds.
Seed Sci. Technol. 23(1): 11–19.
Jacquemart, A.L., Mahy, G., Raspe, O., and DeSloover, J.R. 1994. An isozyme study in bilberry (Vaccinium myrtillus) 2. Mating system and genetic structure.
Belg. J. Bot. 127(2): 105–114.
Jayle, G.E., Aubry, M., Gavini, H., Braccini, G., and De la Baume, C. 1965. Study concerning the action of anthocyanoside extracts of Vaccinium myrtillus on night vision. Ann. Ocul. (Paris) 198: 556–562.
[In French.]
Laplaud, P.M., Lelubre, A., and Chapman, M.J. 1997.
Antioxidant action of Vaccinium myrtillus extract on human low density lipoproteins, in vitro initial ob-servations. Fundam. Clin. Pharmacol. 11(1): 35–40.
Lietti, A., and Forni, G. 1976. Studies on Vaccinium myrtillus anthocyanosides. II. Aspects of anthocyanins pharmacokinetics in the rat. Arzneimittelforschung 26: 832–835.
Lietti, A., Cristoni, A., and Picci, M. 1976. Studies on Vaccinium myrtillus anthocyanosides. I. Vasoprotec-tive and antiinflammatory activity. Arzneimittel-forschung 26: 829–832.
Lorek, E. 1978. Contents of manganese and vitamin C in the fruits of bilberries (Vaccinium myrtillus L.) and red berries (Vaccinium vitis-idaea L.) growing in highly industrialized areas. Rocz. Panstw. Zakl.
Hig. 29: 381–387. [In Polish.]
Luby, J.J., Ballington, J.R. Draper, A.D., Kazimierz, P, and Austin, M.E. 1991. Blueberries and cranberries.
In Genetic resources of temperate fruit and nut crops.
Edited by J.N. Moore and J.R. Ballington. Interna-tional Society for Horticultural Science, Wageningen, The Netherlands. pp. 393–456.
Magistretti, M.J., Conti, M., and Cristoni, A. 1988. Anti-ulcer activity of an anthocyanidin from Vaccinium myrtillus. Arzneimittelforschung 38: 686–690.
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Morazzoni, P., and Magistretti, M.J. 1990. Activity of myrtocyan, an anthocyanoside complex from Vaccin-ium myrtillus (VMA), on platelet aggregation and adhesiveness. Fitoterapia 61: 13–22.
Ritchie, J.C. 1956. Biological flora of the British Isles:
Vaccinium myrtillus L. J. Ecology 44: 290–298.
Rogers, L. 1976. Effects of mast and berry crop failures on survival, growth, and reproductive success of black bears. Trans. N. Am. Wildl. Conf. 41: 431–438.
Sjors, H. 1989. Vaccinium myrtillus, a plant portrait.
Svensk Bot. Tidskr. 83: 411–428. [In Swedish.]
Slosse, P., and Hootele, C. 1978. Structure and absolute configuration of myrtine, a new quinolizidine alka-loid from Vaccinium myrtillus. Tetrahedron Lett. 4:
397–398.
Tolan, L., Barna, V., Szigeti, I., Tecsa, D., Gavris, C., Csernatony, O., and Buchwald, I. 1969. The use of bilberry powder in dyspepsia in infants. Pediatria (Bucur.) 18: 375–379. [In Romanian.]
Vander Kloet, S.P. 1983. Seed and seedling morphology of Vaccinium myrtillus. Nat. Can. 110: 285–292.
Vander Kloet, S.P. 1988.The genus Vaccinium in North America. Research Branch, Agriculture Canada, Ot-tawa, ON. 201 pp.
Woodward, F.I. 1986. Ecophysiological studies on the shrub Vaccinium myrtillus L. taken from a wide
altitudinal range. Oecologia 70: 580–586.
Zaparaniuk, A.E. 1984. Effect of mineral fertilizers on the yields of Vaccinium myrtillus L. fruit. Rastit.
Resur. 20: 358–362. [In Russian.]
World Wide Web Links
(Warning. The quality of information on the internet varies from excellent to erroneous and highly misleading. The links below were chosen because they were the most informative sites located at the time of our internet search. Since medici-nal plants are the subject, information on medicimedici-nal usage is often given. Such information may be flawed, and in any event should not be substituted for professional medical guidance.)
Fire effects information system [general botanical information; excellent!]:
http://svinet2.fs.fed.us/database/feis/plants/shrub/vacmyr/
A modern herbal by M. Grieve:
http://www.botanical.com/botanical/mgmh/b/bilber37.html
Mining Company guide to herbs for health - bilberry [a bilberry feature, with lots of links (mostly non-functional during 1998)]:
http://herbsforhealth.miningco.com/library/weekly/aa081598.htm
Bilberry’s many healing powers [has many references to scientific studies]:
http://www.herbsociety.ca/times3.html
Vaccinium myrtillus [comments on medicinal aspects]:
http://herb.com/files/bilberry.html