encyclopedia

Bilberry Leaf

Scientific Names:    

Vaccinium myrtillus L. [Fam. Ericaceae]    
     

Forms:    

Bilberry leaf tea; Bilberry leaf extract standardized for myrtillin    

     
Traditional Usage:    

– Anti-inflammatory
– Antioxidant
– Appetite Stimulant
– Astringent (externally)
– Blood Purification
– Blood Sugar Balancing
– Bone and Joint Problems
– Breathing Disorders
– Bronchitis
– Circulatory Disorders
– Digestive Disorders
– Gastrointestinal Problems
– Hemorrhoids
– Skin Problems
– Urinary Tract Problems
– Vascular Disorders     
     
    
Overview:    

According to the German Pharmacopoeia, the leaves of bilberry, Vaccinium myrtillus L. [Fam. Ericaceae], were used traditionally as a tea for preventing and treating blood sugar control problems, disorders of the gastrointestinal tract, the kidneys and urinary tract, the respiratory tract, for bone and joint disorders, skin complaints, hemorrhoids, vascular disorders, for stimulating metabolism and for purifying the blood. The leaves are rich in tannins and a compound called myrtillin (methoxylated glucoside of gallic acid), known for its powerful ability to lower and/or normalize hyperglycemia. Both the leaves and berries of bilberry are listed by the German Commission E for their tremendous benefits for individuals unable to control their blood sugar. Myrtillin can safely help to normalize blood sugar levels in many people who have lost this ability. Bilberry leaf also contains remarkably high amounts of chromium (9.0 ppm), which increases the glucose tolerance factor. Chromium enhances insulin's role in oxidizing glucose by up to 100 times. Everyone needs approximately 200 ug per day, but many people do not even get the bare minimum of 50ug. Bilberry leaf tea was one of the top treatments for people suffering from blood sugar disorders before the discovery of insulin. Although less potent than insulin, it is also considered by some researchers to be less damaging to the body over long-term use. The recommended effective dose of myrtillin is 1g/day. A single dosage can produce blood sugar balancing effects lasting for several weeks. Dr. Allen (1927) showed that with this dosage of myrtillin, an individual could quickly become able to make an increase of diet or a decrease of insulin or both, and to prevent hypoglycemic attacks. Modern studies confirm the powerful hyperglycemic effects and other benefits of bilberry leaf and its extract.    
     
    
Active Ingredients:    

The leaves of Bilberry contain: 0.8-6.7% catechol tannins; oligomeric proanthocyanidins; flavonoids including quercetin and quercetin glycosides; myrtillin and neomyrtillin (glucokinins); phenol-carboxylic acids and iridoids; Arbutin and hydroquinone (in trace amounts only); manganese; chromium; quinolizidine alkaloids, myrtine and epimyrtine.    
     
    
Suggested Amount:    

For Hyperglycemia: Unless otherwise prescribed, 1 gram of myrtillin is taken daily. Alternatively, boiling water is poured over two teaspoons of finely chopped bilberry leaves and after ten minutes strained.  Bilberry leaf tea is taken 3-5 times per day, or as required. Bilberry leaf tea is not recommended for prolonged use, due to the high tannin content of the leaves that may damage the liver. One Teaspoon = ca. 0.6 grams.    
     
    
Drug Interactions:    

Bilberry leaf tea and myrtillin extracts may reduce the required dosages of insulin for individuals with blood sugar control difficulties.    
     
    
Contraindications:    

Bilberry leaf tea is not recommended for prolonged use, due to the high tannin content of the leaves that may damage the liver.    
     
    
Side Effects:    

There can be some concern about the effect of long-term tannin exposure to the liver from an aqueous bilberry leaf extract, as opposed to treatment with pure myrtillin, so those interested may want to research this point further. The studies done with Dr. Allan were conducted using purified myrtillin, which he reports, is found in all green plants but is most abundant and easy to isolate from blueberry leaves and other myrtles. One animal study in the older literature reported severe hydroquinone-type poisoning reactions with long-term use of bilberry leaf tea, but these effects were never repeated and it is now understood that hydroquinones and arbutin in bilberry leaf are present only in traces.    
     
    
References:    

Allen F.M. 1927: Blueberry leaf extract: Physiologic and clinical
properties in relation to carbohydrate metabolism. JAMA 89: 1577-1581
 
Anderson, R.A. 1991: Supplemental-chromium effects on glucose, insulin,
glucagon and urinary chromium losses in subjects consuming controlled low
chromium diets. Am. J. of Clin. Nutr. 54: 909-916.
 
Cignarella A, Nastasi M, Cavalli E, Puglisi L. 1996. Novel lipid-lowering properties of Vaccinium myrtillus L. leaves, a traditional antidiabetic treatment, in several models of rat dyslipidaemia: a comparison with ciprofibrate. Res. 1996 Dec 1; 84(5): 311-22.
 
Petlevski R, Hadzija M, Slijepcevic M, Juretic D. 2001. Effect of 'antidiabetis' herbal preparation on serum glucose and fructosamine in NOD mice. J Ethnopharmacol. 2001 May; 75(2-3): 181-4.
 
Wichtl M (ed). 1994. Myrtilli folium – Bilberry leaf In Herbal Drugs and Phyto-pharmaceuticals. (English translation by Norman Grainger Bisset). CRC Press, Stuttgart, pp. 348-350.